System and method for repairing a chain

Abstract

A method of repairing a chain can include aligning an orifice of an outer chain link with an orifice of an inner chain link; inserting a pin through the aligned orifices, the pin having a threaded end opposite a head end; engaging a multi-jack bolt tensioner with the threaded end of the pin, the multi-jack bolt tensioner having a plurality of fasteners; advancing each of the plurality of fasteners to bear against the outer chain link; and forming an interference fit between the pin and the outer chain link at the orifice of the outer chain link as a result of the advancement of the fasteners.

Description

[0001] Cross-reference to related applications

[0002] This application claims priority to U.S. Provisional Patent Application No. 7 / 320,515, filed May 14, 2021, the entire contents of which are incorporated herein by reference.

[0003] Statement regarding federally sponsored research and development

[0004] not applicable. Background Technology

[0005] Industrial chains are used in a variety of industries, including conveyor (or hoist) systems in mines, processing plants, agricultural plants, recycling plants, oil refineries, foundries, and more. While some chains may have a longer lifespan than others, all chains in continuous use eventually require maintenance or will fail due to wear and tear on their components during operation. Typically, chain links are repaired on-site to restore the conveyor system to operation without replacing the entire chain, which would be quite costly.

[0006] However, on-site chain maintenance can be laborious, difficult, tedious, and slow. In many cases, the maintenance location may be cramped or inaccessible to maintenance personnel. Furthermore, tools are typically required as part of the maintenance process, and performing maintenance can be physically and logistically challenging, depending on the size of the tools (considering the space and condition of the workspace used for maintenance) or the availability of the electrical system to operate the tools. Downtime can be very costly if maintenance cannot be implemented quickly, and therefore, there remains a high need for robust and efficient systems for chain maintenance. Summary of the Invention

[0007] This document discloses improved systems and methods for chain maintenance. The disclosed solutions may include a multi-jackbolt tensioner for installing pins that pass through chain links. This multi-jackbolt tensioner can be used without the need for heavy-duty hydraulic or electric equipment, which may not be readily available on-site or can be challenging to use in certain confined environments, thus reducing downtime or the need for specialized equipment for maintenance. Instead, by tightening the various small bolts in the multi-jackbolt tensioner, the end of a replacement pin can be tensioned to install the pin in the chain, and at least in some forms or concepts, after installation / maintenance, the tensioned end of the pin can be broken off or removed from the end of the pin to remove excess length.

[0008] Some embodiments of this disclosure provide a chain repair system. The chain repair system may include inner and outer chain links, each having a corresponding pair of orifices, and also includes a pin. The pin may include a head end defining a head, a threaded end opposite the head end, and a groove introduced into the surface of the pin deeper than the threads. The groove may be located between the head end and the threaded end. The chain repair system may include a multi-push bolt tensioner. The multi-push bolt tensioner may include a plurality of fasteners, a pressure plate having a centrally located locating hole, and a plurality of other threaded holes surrounding the centrally located locating hole. Each fastener may be configured to receive through and threadedly engage with a corresponding hole among the plurality of other holes. The multi-push bolt tensioner may be configured to engage the pin. The multi-push bolt tensioner may be configured to be externally positioned relative to an outer chain link. The multi-push bolt tensioner may be configured to create an interference fit between the pin and the outer chain link at the orifice of the outer chain link.

[0009] In some embodiments, as multiple fasteners travel through the corresponding holes in their pressure plates and, when the pressure plates engage with the pins, the distance between the pressure plates and the outer chain links increases to force the pins through the holes.

[0010] In some embodiments, the pin includes an additional groove that is introduced deeper into the surface of the pin than the threads of the pin, the additional groove being located between the head end and the threaded end. The groove may be introduced into one side of the pin, and the other groove may be introduced into the opposite side of the pin.

[0011] In some embodiments, the groove and another groove are each a V-shaped cut.

[0012] In some embodiments, the thread at the threaded end of the pin defines a first threaded section. The threaded end of the pin may include a second threaded section. A groove may be located between the first and second threaded sections.

[0013] In some embodiments, the groove of the pin defines a bridge portion connecting the first threaded segment to the second threaded segment. In some embodiments, the width of the second threaded segment is smaller than the width of the first threaded segment. In some embodiments, the thickness of the bridge portion is smaller than the width of the second threaded segment.

[0014] In some embodiments, the pin includes a peripheral flange extending around the pin. In some embodiments, the peripheral flange is located between a first threaded section and a second threaded section.

[0015] In some embodiments, when the pin breaks at the groove, the first threaded portion of the pin disengages from the pin.

[0016] In some embodiments, the chain repair system may include a nut configured to threadedly engage a first threaded section of a pin. In some embodiments, an end of the nut is configured to contact an outer chain link.

[0017] In some embodiments, the nut is one of a locking nut and a self-locking nut.

[0018] In some embodiments, an interference fit is created between the pin and the outer chain link as each fastener travels until each head of each fastener contacts the pressure plate.

[0019] In some embodiments, when an interference fit is formed between the pin and the outer chain link, the inner chain link is configured to rotate around the pin.

[0020] In some embodiments, the chain repair system may include another inner chain link having another pair of orifices, another pin, and another multi-push bolt tensioner. In some embodiments, the other pin is configured to receive through another orifice of the outer chain link and an orifice of the other inner chain link. In some embodiments, the other multi-push bolt tensioner is configured to thread-engage the end of the other pin and force the other pin through another orifice of the outer chain link, thereby creating an interference fit between the other pin and the outer chain link at the other orifice.

[0021] In some embodiments, when the multi-push bolt tensioner engages the pin, the multi-push bolt tensioner does not contact the head end of the pin (e.g., the head of the pin).

[0022] A method for repairing a chain is also disclosed herein. The method may include aligning the orifice of an outer chain link with the orifice of an inner chain link, inserting a pin through the aligned orifice, wherein the pin has a threaded end opposite to a head end. The method further includes engaging a multi-push bolt tensioner with the threaded end of the pin (the multi-push bolt tensioner having multiple fasteners), advancing each of the multiple fasteners, pressing against the outer chain link, and, due to the advance of the fasteners, creating an interference fit between the pin and the outer chain link at the orifice of the outer chain link.

[0023] In some embodiments, the method may further include breaking off at least a portion of the threaded end of the pin from the pin at a groove in the pin.

[0024] In some embodiments, the method may include inserting the threaded end of a pin through a hole in an outer chain link that partially defines the orifice of the outer chain link; inserting the threaded end of the pin through two holes in an inner chain link that define the orifice of the inner chain link; threading a central hole in a push plate of a multi-push bolt tensioner with the thread of the pin, the push plate having a plurality of other holes surrounding the central positioning hole, each having threads; threading each fastener with a corresponding hole in one of the plurality of other holes in the push plate; and advancing each of the plurality of fasteners, pressing it against the outer chain link to separate the push plate from the outer chain link.

[0025] In some embodiments, the method may include moving each of a plurality of fasteners in an alternating pattern to iteratively rotate and move the push plate.

[0026] In some embodiments, the method may include disengaging the multi-push bolt tensioner from the pin, and after disengaging the multi-push bolt tensioner from the pin, breaking off a portion of the threaded end of the pin from the pin.

[0027] In some embodiments, the method may include threading a nut to the pin until the nut contacts an outer chain link after at least a portion of the threaded end of the pin has disengaged from the pin.

[0028] This disclosure also provides a pin for repairing a chain having outer chain links and inner chain links using a chain repair system. The pin may include a body having a first cross-section consistent along its entire length; a head coupled to an end of the body, the head having a cross-section larger than the first cross-section of the body; and an extension coupled to an opposite end of the body. The extension may have a first threaded section, a second threaded region, and a groove located between the first and second threaded regions. The groove may be inserted deeper into the surface of the pin than the first and second threaded regions of the pin. The body of the pin may be configured to form an interference fit with an outer chain link at an orifice to engage the outer chain link to the pin. The pin may be configured to break off at the groove, disengaging the first threaded section from the pin.

[0029] The foregoing and other aspects and advantages of this disclosure will be set forth in the description which follows. In this specification, reference is made to the accompanying drawings, which form a part of this specification, in which one or more exemplary versions are illustrated by way of illustration. These versions are not necessarily representative of the full scope of this disclosure. Attached Figure Description

[0030] The following figures are provided to illustrate various features of this disclosure as non-limiting examples, and are not intended to limit the scope of this disclosure or exclude alternative embodiments.

[0031] Figure 1 A perspective view of a chain with links that are not connected and require maintenance (e.g., by joining the links together).

[0032] Figure 2 An exploded view of the chain maintenance system is shown.

[0033] Figure 3A It shows Figure 2 A frontal 3D view of the pins of the chain repair system.

[0034] Figure 3B It shows along Figure 3A The cross-sectional view of the pin taken from line 3B-3B.

[0035] Figure 4 The assembly structure is shown. Figure 2 The image shows a frontal perspective of a chain maintenance system, in which multiple push-bolt tensioners are applied to the chain, but this is before the chain is already tensioned.

[0036] Figure 5 It shows along Figure 4 The line cut from 5-5 Figure 2 A cross-sectional view of the multi-push bolt tensioner and pin engagement in a chain maintenance system.

[0037] Figure 6 It shows Figure 2 A cross-sectional view of the multi-push bolt tensioner and pin engagement in a chain maintenance system.

[0038] Figure 7 The assembly structure is shown. Figure 2 Another perspective view of the chain repair system shows that after the chain links have been repaired, the pins are connected to the outer chain links by applying multiple push bolt tensioners.

[0039] Figure 8 It shows along Figure 7 The line cut from 8-8 Figure 7 A cross-sectional view of the chain maintenance system.

[0040] Figure 9 The assembly structure is shown. Figure 2 Another frontal perspective view of the chain repair system, this is after the chain links have been repaired together, the multi-push bolt tensioner of the chain repair system has been removed, and the nut has been applied to the threaded end of the pin.

[0041] Figure 10 The assembly structure is shown. Figure 2Another frontal perspective view of the chain repair system, after the chain links have been repaired together (e.g., joined together), the nuts have been engaged with the corresponding pins, and a portion of the threaded section of each pin has been removed from or broken off.

[0042] Figure 11 A cross-sectional view of an alternative maintenance system is shown.

[0043] Figure 12 A cross-sectional view of yet another alternative maintenance system is shown.

[0044] Figure 13 A flowchart is shown for the process of repairing a chain.

[0045] Figure 14A It shows Figure 2 A top view of a multi-push bolt tensioner for a chain maintenance system, the multi-push bolt tensioner engaging with pins to show the tightening sequence (e.g., tightening pattern) for the fasteners.

[0046] Figure 14B A top view of another multi-push bolt tensioner engaged with a pin (not shown) is shown, illustrating an iterative fastening pattern.

[0047] Figure 14C It shows Figure 2 A top view of a pair of multiple push bolt tensioners for a chain maintenance system, with each multiple push bolt tensioner engaging with a corresponding pin, showing an iterative fastening pattern for dual tensioner maintenance. Detailed Implementation

[0048] As mentioned above, repairing a chain can be a difficult and time-consuming process. Typically, regardless of how the failure occurred, repairing a chain requires replacing one or more pins to reconnect the disengaged ends of the chain. For example, replacing the pins involves inserting them through pairs of orifices, each through the opposite end of the chain, to join the chain links together. However, conventional repair methods have significant drawbacks.

[0049] For example, in a conventional method, a welding torch can be used to physically attach the end of a replacement pin to one of the chain links. However, welding typically requires a flammable fluid to drive the electrode to melt, and the electrode deposits material to join the two parts together. Furthermore, because industrial chains often operate in enclosed spaces without ventilation, welding cannot be used in such situations (e.g., due to concerns about flammable fluid leaks into the enclosed space), and ideally, repairs must be performed off-site. Additionally, assuming welding is feasible in a given situation, it requires highly skilled operators. Therefore, not every operator, and certainly not many, is capable (or able to come) to repair the chain if it is in use. Moreover, because the replacement pin must be fully inserted through both ends of each orifice before welding, no interference fit is formed at the connection point between the chain link and the pin. This is likely undesirable, at least because each chain link is connected to its adjacent chain link with an interference fit, which is generally a stronger joint than a welded joint. Therefore, because the welded joint is weaker, it is more likely to cause subsequent failures at this weak point compared to other locations, which could be an obstacle for field locations where chains are in use (e.g., because the chain being repaired is weaker than the new chain).

[0050] As another example, in the second conventional method, a grinding machine can be used to physically connect the end of the replacement pin to one of the chain links. However, grinding joints also presents similar problems to welding joints. For example, grinding the joint requires fully inserting the replacement pin through both ends of each orifice before welding, and therefore no interference fit is formed at the connection point between the chain link and the pin. While grinding machines generally do not use flammable fluids and can therefore be used in enclosed spaces, they do require batteries, which must be charged to power the grinding machine. Therefore, the operator must remember to charge the batteries before servicing and to bring the charged batteries (and the grinding machine) to the servicing location. Like the welding method, the grinding method requires a skilled operator to connect the parts, and it may be difficult to find personnel with this skill at the servicing site. Therefore, the chain may need to be taken to an off-site location for servicing, which increases the downtime of the conveyor system (e.g., the time the conveyor system is unusable while the chain is being serviced).

[0051] As another example, in the third conventional method, a manual pneumatic actuator, such as a Lex Nord chain link machine, can be used. Linkmaster and Lex Nord drive ( A drivemaster creates an interference fit between the end of a replacement pin and one of the chain links to physically connect these components. Specifically, in this method, the replacement pin is inserted as far as possible through both orifices, and the drive assembly is positioned around and in contact with both ends of the replacement pin. The operator then continuously drives a manual pump, forcing the replacement pin through the orifices of the chain link, thereby creating the interference fit between the components. While this method does create an interference fit, it requires multiple operators (e.g., three) to secure (or align) the opposing sides of the drive assembly (e.g., ensure proper contact with the pin), and to operate the pneumatic pump to force the drive assembly together to create the interference fit. Furthermore, because this method uses a manual pneumatic actuator, it requires a significant amount of time and manpower to operate the pump and create the interference fit.

[0052] Some embodiments of this disclosure provide solutions to these and other problems by providing improved systems and methods for chain repair. For example, some embodiments of this disclosure provide a chain repair system including a replacement pin with a groove. The replacement pin can be inserted into two aligned orifices, one through an outer chain link and the other through an inner chain link. Subsequently, the replacement pin can be pulled at the end through the orifice of the outer chain link to create an interference fit between the replacement pin and the outer chain link. In some cases, once the replacement pin has been tensioned to a specific force sufficient to create the interference fit between the replacement pin and the outer chain link (e.g., which can be determined by different characteristics of the chain repair system, such as the travel amount of each fastener in a multi-push bolt tensioner), the replacement pin can break at the groove.

[0053] In some embodiments, the chain repair system may include a multi-push-bolt tensioner for pulling a replacement pin through an end of an orifice in an outer chain link, creating an interference fit between the outer chain link and the replacement pin. For example, the multi-push-bolt tensioner may include a push plate and a plurality of threaded holes. The push plate has a centrally located hole configured to receive and threadedly engage the end of the replacement pin, while the plurality of threaded holes surround the centrally located hole. The replacement pin is inserted through two aligned orifices in the inner and outer chain links, respectively, and the end of the replacement pin can threadedly engage with the centrally located hole in the push plate (e.g., threaded engagement can occur once the groove of the pin has traveled to the outside of the outer chain link). Each of the plurality of fasteners then travels, pushing the outer chain link to engage with the replacement pin, creating an interference fit between the outer chain link and the replacement pin.

[0054] In some cases, chain repair systems can include multi-push bolt tensioners, offering significant advantages over previous chain repair systems. First, multi-push bolt tensioners have a much smaller footprint compared to other chain repair systems, and are therefore less bulky and easier to transport. In fact, by using a multi-push bolt tensioner, only a single end of the pin needs to be contacted for chain repair. In other words, for chain repair, the multi-push bolt tensioner preferably does not contact both ends of the pin (e.g., the multi-push bolt tensioner engages only a single end of the pin, such as the threaded end). This is especially useful if the chain is running in tight gaps or confined spaces (e.g., in mines), or if the chain is wide and therefore the replacement pin is long. Therefore, the chain can be repaired on-site at the location of failure or breakage without the assistance of other operators, significantly reducing downtime when the chain is not in use. In fact, because only a single end of the pin needs to be engaged with the multi-push bolt tensioner for replacement, a single operator can perform chain repairs independently. Second, because multi-push bolt tensioners do not require highly skilled operators, most operators can perform chain repairs, thus eliminating the need to transport the chain to a different location for repair. Third, because multi-push bolt tensioners do not require external power sources or power tools for chain repairs such as flammable welding fluids, the chain can be repaired without the risks associated with previous chain repair systems (e.g., leaks of flammable gases from welding fluids). Fourth, chain repairs using multi-push bolt tensioners are significantly faster than with previous chain repair systems. For example, in some cases, a chain can be repaired in 5 minutes using a multi-push bolt tensioner, compared to 1 hour with other chain repair systems (and this doesn't even consider the distance to a repair location).

[0055] Figure 1A chain 100 is shown, having chain links 102 and 104 that are disengaged and are intended for maintenance, for example, by joining chain links 102 and 104 together. As shown, chain link 102 includes plates 106 and 108, bushings 110 and 112, and orifices (channels) 114 and 116. Plates 106 and 108 are spaced apart from each other, and both are connected to bushings 110 and 112. Although plates 106 and 108 are shown as planar rectangles with rounded edges, plates 106 and 108 can be implemented with different shapes or geometries. Each plate 106 and 108 has a hole that can at least partially define a corresponding orifice. For example, plate 106 has holes 118 and 120 that completely guide through plate 106, while plate 108 has holes 122 and 124 that completely guide through plate 108. In some cases, the holes in plates 106 and 108 can provide connection points for bushings 110 and 112. For example, bushing 110 can be inserted through holes 118 and 122 to connect bushing 110 to plates 106 and 108 at these holes 118 and 122 (e.g., by interference fit). Similarly, bushing 112 can be inserted through holes 120 and 124 to connect bushing 112 to plates 106 and 108.

[0056] As shown, orifices 114 and 116 typically provide access channels through the two plates 106 and 108 and between the two plates 106 and 108 at two locations. Therefore, each orifice 114 and 116 is configured to receive pins, such as pins from adjacent chain links. In some cases, such as Figure 1 As shown, bushings 110 and 112 can each completely define their respective orifices 114 and 116, wherein orifices 114 and 116 are coaxially positioned relative to the holes in plates 106 and 108 (e.g., wherein orifice 114 is coaxially positioned relative to holes 118 and 122, and wherein orifice 116 is coaxially positioned relative to holes 120 and 124). In other cases, as described below, the orifices of other chain links can be defined by their respective holes in their plates. For example, orifice 114 can be defined by holes 118 and 122, while orifice 116 can be defined by holes 120 and 124.

[0057] In some embodiments, bushings 110, 112 may include corresponding rollers received coaxially around bushings 110, 112. In other embodiments, bushings 110, 112 may be bushing rollers (e.g., bushing rollers made of steel). Regardless of the specific implementation, the inner surface of each bushing 110, 112 may provide a (lubricated) bearing surface, which may allow a pin passing through one of bushings 110, 112 to roll easily on its inner surface.

[0058] As shown, chain link 104 is constructed in a similar manner to chain link 102 and therefore includes features similar to those of chain link 102. For example, chain link 104 also includes plates 126, 128, bushings 130, 132, and apertures 134, 136. Bushings 130, 132 are each connected to two plates 126, 128, and each plate 126, 128 also includes apertures through which it is completely guided. For example, plate 126 includes apertures 138, 140, while plate 128 includes apertures 142, 144. Similar to chain link 102, bushing 130 is inserted through holes 138, 142 to engage bushing 130 to plates 126, 128 at these holes 138, 142, while bushing 132 is inserted through holes 140, 144 to engage bushing 132 to plates 126, 128 at these holes 140, 144. Also similar to chain link 102, each of bushings 130, 132 may have an inner surface that defines a bearing surface along which the surface of a pin rolls.

[0059] although Figure 1 The chain 100 is shown to have only chain links 102 and 104, but it will be understood that the chain 100 may have other chain links connected to and extending from the chain links 102 and 104. In other words, although chain links 102 and 104 each have a single link, chain links 102 and 104 may have other numbers of links (e.g., a series of chain links).

[0060] Figure 2A cross-sectional view of a chain repair system 150 is shown, which may include chain links 102, 104, 152 (for clarity, link 152 includes a plate that is not part of links 102, 104 as depicted), pins 154, 156, multi-push bolt tensioners 158, 160, and nuts 162, 164. Chain link 152 may be implemented in a similar manner to chain links 102, 104, and may be defined as an outer chain link, while chain links 102, 104 may be defined as inner chain links. For example, chain link 152 may also include plates 166 and 168 that together define orifices 170 and 172. Specifically, plate 166 has holes 174 and 176, and plate 168 also has holes 178 and 180, wherein holes 174 and 178 may jointly define an opening 170, and wherein holes 176 and 180 may jointly define an opening 172. In some configurations, plates 166 and 168 may be structurally similar to each other (e.g., both have the same shape, such as a rectangle with rounded edges). In other configurations, plates 166 and 168 may be constructed differently. In some embodiments, plates 166 and 168 may be structurally similar to the plates of chain links 102 and 104, while in other cases, each of plates 166 and 168 may be constructed in a manner different from the plates of chain links 102 and 104. For example, plates 166 (and plates 168) may have flanges 182 and 183, each extending in opposite directions away from holes 174 and 176. Each of flanges 182 and 183 may include a hole that provides a connection point for the component. For example, flange 182 may include holes 184 and 186 that facilitate the attachment of conveyor components (such as buckets, trays, etc.) by inserting fasteners (e.g., bolts) of the conveyor components through holes 184 and 186 (e.g., by threading holes 184 and 186 with corresponding fasteners). In some embodiments, the hole in flange 183 may also be used to attach flange 182 to the conveyor component in a similar manner.

[0061] In some embodiments, each of the orifices 170, 172 is configured to receive a corresponding pin 154, 156. For example, pin 154 may be inserted through orifice 174 up to a head contact plate 166 having a cross-section larger than that of orifice 176. Similarly, pin 156 may be inserted through orifice 176 up to a head contact plate 166 having a cross-section larger than that of orifice 176. As described in more detail below, as pins 154, 156 are inserted through plate 166, pins 154, 156 may also be inserted through chain links 102, 104. For example, pin 154 is configured to fully extend through orifice 116 of chain link 102 and is configured to partially extend through orifice 178 of plate 168 (e.g., a portion of the threaded end of pin 154 is inserted through orifice 178). Similarly, pin 156 is configured to extend fully through the orifice 134 of chain link 104 and partially through the hole 180 of plate 168 (e.g., a portion of the threaded end of pin 156 is inserted through hole 180). As pins 154 and 156 extend through plate 166, chain links 102 and 104, and plate 168, each of the multiple push bolt tensioners 158 and 160 can engage one of pins 154 and 156. For example, multiple push bolt tensioner 158 is configured to engage pin 154, while multiple push bolt tensioner 160 is configured to engage pin 156.

[0062] like Figure 2As shown, the multi-push bolt tensioner 158 may include a washer 188, a push plate 190, and fasteners 192, 194, 196, 198, 200 (e.g., bolts, screws such as dog point screws, etc.). The washer 188 is shown with a centrally located hole 202 configured to receive part of a pin 154 (e.g., when the pin 154 receives a hole 178 through plate 166). Although the washer 188 is shown as circular and planar, it may also take other shapes and spatial configurations (e.g., non-planar). The push plate 190 may include a centrally located hole 204 and holes 206, 208, 210, 212, 214 surrounding the centrally located hole 204. Although holes 206, 208, 210, 212, and 214 are located on push plate 190 and thus form a star array, in alternative configurations, holes 206, 208, 210, 212, and 214 can be positioned relative to each other in different ways. Alternatively, while the illustrated configuration has five holes 206, 208, 210, 212, and 214, in other embodiments, push plate 190 can have other numbers of holes (e.g., four, six, etc.). Correspondingly, the number of fasteners can match the number of holes; therefore, for example, if push plate 190 has four holes, multi-push bolt tensioner 158 can have four fasteners. Each of holes 206, 208, 210, 212, and 214 can be threaded to threadedly engage the corresponding fastener 192, 194, 196, 198, and 200. Additionally, hole 202 can also be threaded to threadedly engage a portion of pin 154.

[0063] In some embodiments, and as Figure 2 As shown, each of the multi-push bolt tensioners 158 and 160 can be constructed in a similar manner. Therefore, similar to multi-push bolt tensioner 158, multi-push bolt tensioner 160 can also include a washer, a push plate, and a plurality of fasteners, the push plate having a centrally located hole and a plurality of other holes surrounding the centrally located hole, each fastener threadedly engaging one of the plurality of other holes in the push plate. Because multi-push bolt tensioners 158 and 160 can be constructed in a similar manner, the above description of multi-push bolt tensioner 158 also applies to multi-push bolt tensioner 160.

[0064] In some embodiments, some components of chain links 152, pins 154, 156, and multi-push bolt tensioners 158, 160 may be heat-treated. For example, plates 166, 168 of chain link 152, pins 154, 156, washers of multi-push bolt tensioners 158, 160, and push plates of multi-push bolt tensioners 158, 160 may each be heat-treated (e.g., and correspondingly made of metal). For example, washers and push plates of multi-push bolt tensioners 158 and 160 may be heat-treated and hardened. Additionally, pins 154 and 156 may also be heat-treated and through-hardened, or may be induction hardened. In some cases, pins 154 and 156 may be through-hardened and induction hardened.

[0065] In some embodiments, the chain repair system 150 may include one or more tethers (not shown), each tether corresponding to a given fastener. Each tether may have a first loop positioned at one end of the tether and a second loop positioned at the opposite end of the tether. The first loop of each tether wraps around a plate 168, and the second loop of each tether is inserted through the first loop. Subsequently, each fastener is inserted into the second loop of each tether. In an alternative configuration, each fastener may be inserted into a loop of the tether, and the opposite loop of each tether may engage with a protrusion of the plate 168. In yet another alternative configuration, each tether may temporarily bind each pin to the plate 168. Regardless of the configuration, in the event of a partial breakage of the pin 154 during the repair process, the tether may help hold the multi-push bolt tensioner 158 (including other components, such as portions of the pin 154) near the chain link 152.

[0066] Figure 3A A perspective view of pin 154 is shown, while Figure 3B Pin 154 is shown along Figure 3A The cross-sectional view taken from line 3B-3B. (See figure.) Figure 3A and 3B As shown, pin 154 includes a body 216, a head end portion 218 positioned at one end of the body 216, and an extension defining a threaded end portion 220 located at the opposite end of the body 216. In some cases, the head end portion 218 may be integrally formed with the body 216, and the threaded end portion 220 may be integrally formed with the body 216. In some embodiments, and as shown, the body 216 of pin 154 may have a uniform cross-section along its length, which may be larger than the cross-section of all portions of the threaded end portion 220 of the pin, and may be smaller than the cross-section of the head 222 of the head end portion 218. In some embodiments, the head 222 may include a recess 224 introduced into the end of the head 222, which may be implemented to have various shapes (e.g., rectangular).

[0067] like Figure 3B As shown, the threaded end 220 of pin 154 may have threaded sections 226, 228 and grooves 230, 232 located between the threaded sections 226, 228. The threaded section 228 is located closer to the body 216 of pin 154 than the threaded section 226, and its cross-section is larger than that of the threaded section 226. Each of the threaded sections 226 and 228 has threads to threadedly engage components. For example, threaded section 226 is configured to threadedly engage a centrally positioned hole 204 of push plate 190, while threaded section 228 is configured to threadedly engage nut 162. Threaded sections 226 and 228 are connected together by a bridge 234. In some cases, the thickness of the bridge 234 (e.g., relative to...) Figure 3B The cross-sectional view of the bridge portion 234 is smaller than the width (e.g., diameter) of the threaded segments 226 and 228. The relatively small thickness of the bridge portion 234 makes removal of the threaded segment 226 (e.g., after repair) easier (e.g., because of the smaller thickness). In some cases, the shape of the bridge portion 234 may be defined by the grooves 230 and 232. For example, the groove 230 is introduced into one side of the pin 154, so the depth of the groove 230 extending into the surface of the pin 154 is greater than the threads of the threaded segment 226 (and the threads of the threaded segment 228), while the groove 232 is located on the other side of the pin 154, so the depth of the groove 230 extending into the surface of the pin 154 is greater than the threads of the threaded segment 226 (and the threads of the threaded segment 228). Because the grooves 230 and 232 are V-shaped cuts in the illustrated embodiment, the bridge portion 234 has a rectangular shape. However, in other configurations, the grooves 230, 232, and the bridge portion 234 may have other shapes or geometries. For example, in some cases, the pin 154 in the same area may have a circumferential groove extending around the entire pin 154, instead of multiple grooves 230, 232. In this case, the bridge portion 234 may have other shapes, such as cylindrical or circular.

[0068] In some embodiments, and as Figure 3BAs shown, pin 154 may include a peripheral flange 236 that may extend circumferentially (e.g., partially or completely) around pin 154. In some cases, the peripheral flange 236 extends radially beyond threaded segment 226, and therefore the cross-section (e.g., diameter) of the peripheral flange 236 may be larger than the cross-section (e.g., diameter) of threaded segment 226 of pin 154. The peripheral flange 236 is positioned between threaded segments 226 and 228, and particularly at the end of threaded segment 226 closer to the body 216 of pin 154 (e.g., not at the free end of threaded segment 226). In some cases, the peripheral flange 236 advantageously provides a stop point for push plate 190. In other words, push plate 190 at the centrally located hole 204 can be screwed onto threaded segment 226 of pin 154 until push plate 190 contacts peripheral flange 236. This provides the operator with tactile feedback on when to stop tightening the push plate 190 and also prevents the push plate 190 from moving further toward the body 216 of the pin 154 during the maintenance process.

[0069] Similar to the multi-push bolt tensioners 158 and 160, in some configurations, pins 154 and 156 can be constructed in a similar manner, and therefore the previous description of pin 154 also applies to pin 156. For example, pin 156 may also include threaded sections separated by bridges, grooves, outer peripheral flanges, etc.

[0070] Figure 4 The diagram shows a front perspective view of the chain maintenance system 150 in its assembled configuration, but before the multi-push bolt tensioners 158 and 160 have been tightened. For example, pins 154 and 156 have been inserted through plate 166, through the holes of the corresponding chain links 102 and 104, and through plate 168. More specifically, the threaded end 220 of pin 154 is inserted through hole 174 in plate 166, through hole 116 in chain link 102, and through hole 178 in plate 168. Thus, the threaded end 220, and in particular the threaded sections 226, grooves 230 and 232, and a portion of the threaded section 228, are outside chain link 152 (e.g., outside plate 168). Similarly, because the cross-section of the head end 218 of pin 154, and especially the head 222, is larger than the cross-section of the hole 176 of plate 166, when pin 154 is inserted through the holes 170, 116, the head end 218 of pin 154 is outside the chain link 152 (e.g., outside plate 166).

[0071] As pins 154 and 156 are inserted (in a similar manner to each other), the multi-push bolt tensioners 158 and 160 can engage with the corresponding pins 154 and 156. For example, the threaded end 220 of pin 154 can be inserted through the hole 202 of washer 188 until washer 188 contacts chain link 152 (e.g., plate 168 of chain link 152). Subsequently, the threaded end 220 of pin 154, and particularly the second threaded section 226, can engage with the hole 204 of push plate 190, and push plate 190 can travel until the surface of push plate 190 contacts the outer peripheral flange 236. Subsequently, each of the fasteners 192, 194, 196, 198, and 200 can thread into the corresponding holes 206, 208, 210, 212, and 214, and can proceed until each fastener 192, 194, 196, 198, and 200 contacts the washer 188 (or plate 168, such as when washer 188 is omitted). Because the multi-push bolt tensioners 158 and 160 are constructed in a similar manner, the multi-push bolt tensioner 160 can engage with the pin 156 (e.g., the threaded end of the pin 156) in a similar manner to the engagement pin 154 of the multi-push bolt tensioner 158.

[0072] Figure 5 This illustrates the process of maintaining chain links 102, 104 before maintenance (e.g., before an interference fit is formed between chain link 152 and pin 154). Figure 4 The cross-sectional view of the multi-push bolt tensioner 158, which engages with pin 154, is taken from line 5-5. (See diagram below.) Figure 5 As shown, the end of each of fasteners 192, 196 and 198 contacts washer 188.

[0073] In some embodiments, each of the multiple push bolt tensioners 158, 160 may include a sleeve that can receive a portion around each pin 154, 156. For example, as Figure 6As shown, the multi-push bolt tensioner 158 may include a sleeve 191 that may include a guide hole 193 therethrough. Before the push plate 190 is positioned to engage with the pin 154 and washer 188, the sleeve 191 may be positioned around the threaded portion 228 of the pin 154. The washer 188 may then be received around the sleeve 191 (e.g., the sleeve 191 is inserted into a hole 202 through the washer 188). In this way, the sleeve 191 protects the threads of the threaded portion 228 of the pin 154 and guides the washer 188 into proper position, which is important because the washer 188 distributes compressive force to the plate 168 (e.g., via a fastener of the multi-push bolt tensioner 158). In some embodiments, the sleeve 191 may be made of a plastic material, while in others, the sleeve 191 may be made of metal. In some configurations, the sleeve of the multi-push bolt tensioner 160 can be constructed in a similar manner to the sleeve 191 of the multi-push bolt tensioner 158.

[0074] Figure 7 The diagram shows a view of a chain repair system 150 with chain links 102 and 104 repaired together (e.g., joined together) and plates 166 and 168 pressed into place by multi-push-bolt tensioners 158 and 160. Figure 8 It shows along Figure 7 The line cut from 8-8 Figure 7 A 150-degree cross-sectional view of the chain repair system. (See attached image.) Figure 8 As shown, each of fasteners 192, 196, and 198 has been advanced (e.g., by further tightening) until each head of each fastener 192, 196, and 198 contacts the push plate 190. Similarly, although Figure 7 Not shown, but fasteners 194, 200 have also advanced until each head of each fastener 194, 200 contacts push plate 190. Thus, as fasteners 192, 194, 196, 198, 200 advance, push plate 190 is forced further away from chain link 152 (e.g., plate 168 of chain link 152). This simultaneously forces the body 216 of pin 154 through hole 178 in plate 168 of chain link 152, creating an interference fit between the body 216 of pin 154 and plate 168 at hole 178. In other words, the inner surface of hole 178 defining plate is forced into contact with the surface of pin 154 body 216 to create an interference fit between pin 154 and plate 168 (e.g., where pin 154 is fixed in place relative to plate 166).

[0075] In some embodiments, different factors can affect the degree of interference fit between the body 216 of pin 154 and plate 168 (e.g., the clamping force from plate 168 to pin 154). For example, the length of each fastener (e.g., the distance between the surface of push plate 190 and plate 168 when each end of each fastener contacts washer 188 (or plate 168) and each head of each fastener contacts push plate 190), the thickness of push plate 190 (and the length of the corresponding hole), the cross-sectional dimensions of the pin 154 body 216, the cross-sectional dimensions of the hole 178, the material of the pin 154 body 216, and the material of plate 168 can each affect the degree of interference fit between the pin 154 body 216 and plate 168. In some cases, such as Figure 8 As shown, when an interference fit is formed between the body 216 of pin 154 and plate 166 at hole 178, a gap 238 is created between plate 106 of chain link 104 and plate 168 of chain link 152. Thus, even with the interference fit between pin 154 and plate 168, chain link 102 can still rotate about pin 154. In other words, gap 238 is sized to allow sufficient clearance between plates 106 and 168 to allow chain link 102 to rotate about pin 154. In some cases, the various factors described above that affect the degree of interference fit can be selected (e.g., implemented) to produce a gap 238 sized sufficiently to allow chain 102 to rotate about pin 154 while still creating an interference fit between pin 154 and plate 168.

[0076] In some embodiments, the fasteners of the multi-push bolt tensioners 158 and 160 and the fasteners between the multi-push bolt tensioners can travel iteratively. For example, one fastener of the multi-push bolt tensioner 158 can travel, followed by one fastener of the multi-push bolt tensioner 160 (e.g., the same fastener of the multi-push bolt tensioner 160) can travel, followed by another fastener of the multi-push bolt tensioner 158 can travel, and then another fastener of the multi-push bolt tensioner 160 can travel. Thus, the push plate for each of the multi-push bolt tensioners 158 and 160 can travel away from plate 168 by the same amount (and in the same orientation, such as traveling in the same order for each fastener in the multi-push bolt tensioners 158 and 160). In some embodiments, the fastening sequence within each multi-push bolt tensioner 158 and 160 can be the same. In some cases, the fastening sequence of the fasteners of the multi-push bolt tensioner 158 can be clockwise, counterclockwise, star-shaped (e.g., where the first fastener is fastened, the second fastener opposite the first fastener is fastened, and so on).

[0077] Figure 9The diagram illustrates a chain repair system 150 with the chain links 102, 104 repaired by introducing link 152 (i.e., plates 166, 168) and the multi-push bolt tensioners 158, 160 removed. For example, after an interference fit is formed between pin 154 and plate 168, and an interference fit is formed between pin 156 and plate 168, the multi-push bolt tensioner 158 can be disengaged from pin 154, and the multi-push bolt tensioner 160 can be disengaged from pin 156. For example, each of fasteners 192, 194, 196, 198, 200 can be retracted (and removed from engagement with their respective holes 206, 208, 210, 212, 214). Subsequently, the push plate 190 can be retracted from the threaded section 226 of the pin 154 (and removed from engagement with the threaded section), and the washer 188 can be removed from the pin 154. These processes can also be repeated to disengage the multi-push bolt tensioner 160 from the pin 156. Figure 9 As shown, with the removal of the multi-push bolt tensioners 158 and 160, several portions of each of pins 154 and 156 are located outside plate 168. For example, the threaded portion 226, grooves 230, 232, and a portion of the threaded portion of pin 154 (e.g., larger than the portion before the repair) are positioned externally relative to plate 168.

[0078] In some cases, after the multi-push bolt tensioners 158, 160 have been disengaged from their respective pins 154, 156, nuts 162, 164 can be threadedly engaged with their respective pins 154, 156. For example, nut 162 can be threadedly engaged and tightened with the threaded portion 228 of the pin until it contacts plate 168. Similarly, nut 164 can be threadedly engaged and tightened with the threaded portion of pin 156 closer to plate 168 until it contacts plate 168. Each of these nuts 162, 164 can reinforce the connection between pins 154, 156 and plate 168 and prevent potential axial slippage of pins 154, 156. In some configurations, additional fastening mechanisms can provide additional reinforcement between pins 154, 156 and plate 168. For example, adhesive can be applied to the junction of holes 178, 180 in plate 168 and a portion of pins 154, 156. As a more specific example, adhesive may be applied to each hole of each nut 162, 164 before fastening to pins 154, 156. In this way, the adhesive, once cured, further strengthens the connection between nuts 162, 164, the corresponding pins 154, 156, and plate 168. In some embodiments, nuts 162, 164 may be locking nuts, self-locking nuts, etc.

[0079] Figure 10 It shows something similar to Figure 9A perspective view of the assembled chain repair system 150, but after the threaded sections of each pin 154 and 156 have been removed. In some embodiments, after the nuts 162 and 164 have been threadedly engaged with the corresponding pins 154 and 156, the threaded sections of each pin 154 and 156 further from the plate 168 can be removed. For example, the threaded section 226 can be disengaged from the pin 154 by shearing the bridge portion 234 (e.g., with a grinding or cutting tool), bending the threaded section 226 around the bridge portion 234 (e.g., using a torque bar positioned on the threaded section 226 and rotated to disengage the bridge portion 234), twisting the threaded section 226 around the longitudinal axis of the pin 154 (e.g., the longitudinal axis extends along the length of the pin 154), or pulling the threaded section 226 along the longitudinal axis of the pin 154. In some cases, removing the threaded sections of each pin 154 and 156 further from the plate 168 does not involve using a flame (e.g., a spray gun). In this way, because the parts being repaired are not heated, the connection provided by the interference fit will not be undesirably degraded or intermittently affected by the applied heat. Regardless of how the threaded sections of pins 154 and 156 are removed, once an interference fit is formed only between pin 154 and plate 168, or additionally between pin 156 and plate 168, chain links 102 and 104 can be re-linked together (e.g., via chain link 152) and chain 100 can be reused.

[0080] Figure 11 A cross-sectional perspective view of an alternative repair system 300 is shown, and the engagement between the threaded end of the pin and the multi-push bolt tensioner differs. Chain repair system 300 can be implemented in a similar manner to chain repair system 150, and therefore the previous description of chain repair system 150 generally applies to chain repair system 300, except for the differences discussed below and shown in the figures. Chain repair system 300 may include chain links 102, alternative pins 302, and multi-push bolt tensioners 304, the chain links including plates 166 and 168. Pin 302 may define a body 306 having a uniform cross-section over its entire length, a head end 308 located at one end of the body 306 and including a head 310, and a threaded end 312 located at the opposite end of the body 306 and including a threaded segment 314. Figure 11 As shown, and unlike the pin depicted above, pin 302 also includes an orifice 316 axially introduced into a threaded section 314, which may include threads. In some cases, the outer surface of the threaded section 314 of pin 302 may also include threads.

[0081] The multi-push bolt tensioner 304 may include a washer 317, a push plate 318, fasteners 320, 322, 324, and, notably, a new center fastener 326. Although not in Figure 11 As shown, but the multi-push bolt tensioner 304 may have two additional (or other numbers) fasteners (e.g., in a manner similar to multi-push bolt tensioners 158 and 160). In some embodiments, and as depicted, the cross-section of the center fastener 326 may be larger than that of fasteners 320, 322, and 324. Figure 11 As shown, the central fastener 326 is threadedly engaged with the centrally positioned hole (surrounded by a plurality of other holes) of the push plate 318 and threadedly engaged with the orifice 316 of the pin 302. This restricts relative movement between the pin 302 and the push plate 318, so that when the other fasteners 320, 322, 324 travel and force the body 306 of the pin 302 to engage with the plate 168 at the hole 178, the push plate 318 is not separated from the pin 302 (e.g., ensuring that the travel of the fasteners pushes the plate 168 onto the pin 302, rather than separating the pin 302 from the push plate 318). Additionally, in this alternative, the pin 302 does not include a plurality of threaded sections and does not include grooves (and corresponding bridges) separating the threaded sections of the pin. Therefore, in this disclosed alternative, after the interference fit is formed, the threaded sections of the pin do not need to be directly disengaged from or unscrewed from the push plate. This makes the installation of the multi-push bolt tensioner onto the pin more user-friendly, as the user does not need to rotate the push plate or the entire multi-push bolt tensioner relative to the pin, which could be somewhat cumbersome given that the pin is not yet in place. Instead, only one fastener (i.e., fastener 326) needs to be bolted or secured, which can be easier to start and subsequently aided by hand tools or the like.

[0082] Figure 12 A cross-sectional view of yet another maintenance system 350 is shown, but in which the push plate 370 of the multi-push bolt tensioner is engaged with the pin 352 using a nut 372 (instead of screwing the push plate directly onto the pin as in the first embodiment, or having the pin with a central fastener as in the second embodiment). The chain maintenance system 350 can be implemented in a similar manner to chain maintenance systems 150 and 300, and therefore the descriptions of the previous chain maintenance systems 150 and 300 generally apply to chain maintenance system 350, except for the differences discussed below.

[0083] The chain maintenance system 350 may include chain links 102, pins 352, and a multi-push bolt tensioner 354. The chain links include plates 166 and 168. Pin 352 may define a body 356, a head end 358 located at one end of the body 356 and including a head 360, and a threaded end 362 located at the opposite end of the body 356 and including threaded segments 364 and 366, wherein the body 356 has a uniform cross-section over its entire length. Additionally, pin 352 also includes a circumferential groove 368 positioned between the threaded segments 364 and 366, and extending entirely around pin 352. Each of the threaded segments 364 and 366 may include threads for threadably engaging components.

[0084] In this form, the multi-push bolt tensioner 354 may include a washer 367, a push plate 370, a nut 372, and fasteners 374, 376, and 378. Although not in... Figure 12 As shown, however, the multi-push bolt tensioner 354 may have several additional fasteners (e.g., in a similar manner to multi-push bolt tensioners 158 and 160). Figure 12 As shown, push plate 370 includes a centrally located hole 380 and a plurality of other holes surrounding the centrally located hole 380. A portion of pin 352 receives through the hole 380 of push plate 370, and nut 372 is threadedly engaged with a threaded portion 364 of pin 352. Thus, push plate 370 is positioned between nut 372 and plate 168, and the surface of push plate 370 contacts the surface of nut 372 to reduce (e.g., prevent) relative movement between push plate 370 and pin 352 during the travel of fasteners 374, 376, 378, etc. In some embodiments, the surface of push plate 370 may surround the centrally located hole 380, may be concave, and may be spherical. Correspondingly, the surface of nut 372 may be convex and may be partially spherical to be received or nested in the recess of push plate 370. As fasteners 374, 376, and 378 (and other fasteners) travel through the corresponding holes in push plate 370, push plate 370 engages nut 372 to pull pin 352, while plate 168 presses against body 356 of pin 352 to create an interference fit between body 356 of pin 352 and plate 168.

[0085] Figure 13 A flowchart is shown of a process 400 for generally repairing a chain (e.g., a chain with multiple chain links), which implements the disclosed components. This process 400 can be implemented using any of the chain repair systems described above (such as chain repair systems 150, 300, 350) or variations thereof.

[0086] In step 402, process 400 may include aligning the orifice of a first chain link (e.g., an outer chain link) with the orifice of a second chain link (e.g., an inner chain link). In some embodiments, this may include aligning the orifice of the first chain link with the orifice of the second chain link. For example, a hole in the plate of the first chain link (e.g., hole 174) may be aligned with an orifice of the second chain link (e.g., hole 116 of chain link 102). In some embodiments, such as when more than one pin is needed to service the chain, step 402 of process 400 may include aligning another orifice of the first chain link with the orifice of a third chain link (e.g., chain link 104). In some cases, this may include aligning another orifice of the first chain link with the orifice of the third chain link. For example, a hole in the plate of the first chain link (e.g., hole 180) may be aligned with another orifice of the second chain link.

[0087] In step 404, process 400 may include inserting a pin through a hole in a chain link (e.g., an aligned hole in a chain link). In some embodiments, this may include inserting the threaded end of the pin through a hole (e.g., hole 174) in a first plate of a first chain link, inserting the threaded end of the pin through a hole (e.g., hole 116) in a second chain link, and inserting the threaded end of the pin through a hole in another plate of the first chain link. In some embodiments, such as when more than one pin is needed to service the chain, step 404 of process 400 may include inserting another pin through another pair of holes in a chain link. For example, this may include inserting another pin through a hole in a first chain link and through a hole in a third chain link. In this case, this may include inserting the threaded end of another pin into another hole (e.g., hole 176) through the first plate of the first chain link, passing the threaded end of another pin through the hole of the third chain link (e.g., hole 134 of chain link 104), and inserting the threaded end of another pin into another hole through the other plate of the first chain link.

[0088] In step 406, process 400 may include engaging the multi-push bolt tensioner with a pin. In some embodiments, this may include placing a washer around a portion of the threaded end of the pin and contacting a plate of a first chain link, fixing a push plate relative to the pin to reduce relative movement between the push plate and the pin (e.g., reducing relative movement between the push plate and the pin), and threadedly engaging a fastener with each of a plurality of holes in the push plate until the end of each fastener presses against chain link 152 (e.g., contacting the washer or chain link). In some cases, this may include threadedly engaging a centrally located hole in the push plate of the multi-push bolt tensioner (e.g., and advancing the push plate until it contacts the outer peripheral flange of the pin), inserting a portion of the threaded end of the pin through the centrally located hole in the push plate and subsequently threadedly engaging a nut (e.g., nut 372) with a portion of the threaded end of the pin, and threadedly engaging a fastener with an orifice of the pin (e.g., fastener 326 with orifice 316 of pin 302). 0 In some cases, such as when more than one pin is needed to repair the chain, block 402 of process 400 may include engaging another multi-push bolt tensioner with another pin.

[0089] In step 408, process 400 may include advancing multiple fasteners of the multi-push bolt tensioner to push them onto a first chain link (e.g., a plate of the first chain link). In some cases, this may include advancing the multiple fasteners of the multi-push bolt tensioner according to a tightening sequence. For example, Figure 14A A top view of the multi-push bolt tensioner 158, which engages with pin 154, is shown to illustrate the tightening sequence (e.g., tightening pattern) for fasteners 192, 194, 196, 198, and 200. Figure 14AAs shown, the fastener can be fastened according to the fastening pattern by the following steps: advancing the fastener 196 further toward the first chain link (e.g., denoted as "1") by a specific amount, then advancing the fastener 200 (e.g., denoted as "2") opposite the fastener 196 by approximately that specific amount (e.g., with a deviation less than or equal to 20% of that specific amount), then advancing the fastener 192 (e.g., denoted as "3") opposite the fastener 200 by approximately that specific amount (but it has not yet been fastened with the fastening pattern), then advancing the fastener 198 (e.g., denoted as "4") opposite the fastener 192 by approximately that specific amount, and then advancing the fastener 194 (e.g., denoted as "5") opposite the fastener 198 by approximately that specific amount (but it has not yet been fastened with the fastening pattern). This fastening pattern can be repeated as needed until each head of each fastener 192, 194, 196, 198, 200 contacts the push plate 190. This fastening pattern allows for a star-shaped fastening pattern, but in alternative configurations, the fastening pattern can be different. For example, the fastening pattern can follow a clockwise fastening pattern, and the fasteners can be fastened in this order: fasteners 196, 198, 200, 194, 192. Alternatively, the fastening pattern can follow a counter-clockwise fastening pattern, and the fasteners can be fastened in this order: fasteners 196, 192, 194, 200, 198.

[0090] In some embodiments, such as when the number of fasteners in a multi-push bolt tensioner is even, pairs of fasteners positioned on opposite portions of the push plate can be iteratively tightened. For example, Figure 14B A top view of a multi-push bolt tensioner 450 engaged with a pin (not shown) is shown, illustrating an iterative fastening pattern. The multi-push bolt tensioner 450 may include a push plate 452 and fasteners 454, 456, 458, 460, 462, and 464, each threadedly engaged with the push plate 452 and actuated on a first chain link. Figure 14BAs shown, fastener 454 is opposite fastener 460, fastener 456 is opposite fastener 462, and fastener 458 is opposite fastener 464. The fasteners can be tightened according to an iterative tightening pattern by the following steps: advancing fastener 454 further toward the first chain link (e.g., denoted as "1") by a specific amount, then advancing fastener 460 (e.g., denoted as "2") opposite fastener 454 by approximately that specific amount (e.g., a deviation less than or equal to 20% of the specific amount), then advancing fastener 456 (e.g., denoted as "3") by approximately that specific amount, then advancing fastener 462 (e.g., denoted as "4") opposite fastener 456 by approximately that specific amount, then advancing fastener 458 (e.g., denoted as "5") by approximately that specific amount, and then advancing fastener 464 (e.g., denoted as "6") opposite fastener 458 by approximately that specific amount. This fastening pattern can be repeated as needed until each head of each fastener 454, 456, 458, 460, 462, 464 contacts the push plate 452.

[0091] In some embodiments, such as when more than one pin is needed to service the chain, the fasteners for a multi-push-bolt tensioner that engages with the respective pin can collectively define a fastening pattern. For example, Figure 14C A top view of the multi-push bolt tensioners 158 and 160, each engaging with corresponding pins 154 and 156, is shown. In some cases, a common fastening pattern may include advancing one fastener of the multi-push bolt tensioner 158, followed by advancing one fastener of the multi-push bolt tensioner 160 (e.g., before fastening the other fasteners of the multi-push bolt tensioner 158, and which may be in the same position as the fasteners of the multi-push bolt tensioner 158), and so on. In this case, because the advance of the fasteners switches between each multi-push bolt tensioner 158 and 160, the magnitude of the compressive force acting on the first chain link provided by each multi-push bolt tensioner 158 and 160 is approximately the same. Thus, the tilt of the plate (e.g., plate 168) of the first chain link closer to the multi-push bolt tensioners 158 and 160 is reduced.

[0092] In step 410, process 400 may include determining that all fasteners of the multi-pin bolt tensioner have traveled a specific amount (e.g., the amount required to create an interference fit between the first chain link and the pin). If it is determined in step 410 that the fasteners have not traveled a specific amount, process 400 may return to step 408 to continue traveling the fasteners (e.g., according to the fastening pattern). If it is determined in step 410 that all fasteners of the multi-push bolt tensioner (or multiple multi-push bolt tensioners) have traveled a specific amount (e.g., until each head of each fastener contacts the push plate), process 400 may proceed to step 412. In some embodiments, during (or after) steps 408, 410, process 400 includes creating an interference fit between the pin and the plate of the chain link at the orifice of the first chain link (e.g., a hole in the plate of the first chain link).

[0093] In step 412, process 400 may include disengaging the multi-push bolt tensioner from the pin. In some cases, this may include removing a nut (e.g., nut 372) from the pin (e.g., by threading the nut off the pin), removing each fastener from the push plate (e.g., by threading each fastener off the push plate), removing the push plate from the pin, removing the fasteners from the pin, and removing the washer from the pin. In some embodiments, such as when more than one pin is needed to service the chain, each multi-push bolt tensioner may be disengaged from each pin.

[0094] In step 414, process 400 may include placing a nut on the end of each pin. For example, this may include threaded engagement of the nut with the threaded end of the pin (e.g., the threaded portion of the pin closer to the first chain link). Furthermore, each nut may travel along each pin until each nut contacts the first chain link.

[0095] In step 416, process 400 may include disengaging a portion of the pin from the pin. For example, this may include (in a tensile manner) pulling a first threaded section of the pin (e.g., located distal from a first chain link) away from the pin, causing the first threaded section to fail at the bridge portion of the pin (e.g., between grooves). As another example, this may include bending the first threaded section of the pin at the bridge portion, causing the first threaded section to fail at the bridge portion of the pin. In some cases, a torque bar (e.g., a lever) may be received on the first threaded section and rotated to provide a bending torque to break the first threaded section of the pin via bending failure. As yet another example, this may include twisting the first threaded section of the pin about the longitudinal axis of the pin to break the first threaded section of the pin at the bridge portion via torsional failure. As yet another example, this may include shearing the first threaded section of the pin from the pin at the bridge portion to break the first threaded section from the pin. In some cases, this may include grinding or cutting off the first threaded section of the pin at the bridge portion.

[0096] This disclosure has described one or more preferred embodiments, and it should be understood that many equivalents, substitutions, variations and modifications can be made within the scope of the invention, in addition to those expressly stated.

[0097] It should be understood that this disclosure is not limited to applying it to the structural details and component arrangements described in the following specification or drawings. This disclosure can have other embodiments and can be practiced or implemented in various ways. Moreover, it should be understood that the wording and terminology used herein are for descriptive purposes and should not be considered limiting. The terms “comprising,” “including,” or “having,” and variations thereof, as used herein, mean including the articles listed thereafter and their equivalents, as well as additional articles. Unless otherwise specified or limited, the terms “mounted,” “connected,” “supported,” and “coupling,” and variations thereof, are used broadly and include direct and indirect mounting, connection, support, and coupling. Furthermore, “connection” and “coupling” are not limited to physical or mechanical connections or couplings.

[0098] As used herein, unless otherwise limited or restricted, discussions of particular embodiments or related descriptions are provided by way of example only regarding specific orientations. For example, discussions of “top,” “front,” or “rear” features are generally intended only to describe the orientation of these features relative to a reference frame of a particular example or illustration. Accordingly, for example, in some arrangements or examples, a “top” feature may sometimes be positioned below a “bottom” feature (etc.). Furthermore, references to a particular rotation or other movement (e.g., counterclockwise rotation) are generally intended only to describe movement relative to a reference frame of a particular example illustrated.

[0099] Certain operations of the methods according to this disclosure, or certain operations of the systems performing these methods, may be schematically illustrated in the accompanying drawings or otherwise discussed herein. Unless otherwise stated or limited, the representation of particular operations in a particular spatial order in the accompanying drawings may not necessarily require those operations to be performed in a specific order corresponding to that particular spatial order. Accordingly, for particular embodiments of this disclosure, certain operations illustrated in the accompanying drawings or disclosed herein may be performed in an order different from the order explicitly shown or described. Further, in some embodiments, certain operations may be performed in parallel, including by dedicated parallel processing means or separate computing means configured to interoperate as part of a large system.

[0100] In some implementations, methods embodying aspects of this disclosure may be used to utilize or install the devices or systems disclosed herein. Accordingly, the descriptions herein of specific features, capabilities, or intended purposes of devices or systems are generally intended to inherently include methods for utilizing those features for their intended purposes, methods for implementing those capabilities, and methods for installing the disclosed (or otherwise known) components to support those purposes or capabilities. Similarly, unless otherwise indicated or limited, any discussion herein of methods for making or using a particular device or system (including installing the device or system) is intended to inherently include, as embodiments of this disclosure, the features utilized and capabilities implemented by such devices or systems.

[0101] As used herein, unless otherwise defined or limited, for ease of reference, numbering is generally based on the order in which specific components are presented with respect to relevant parts of this disclosure. In this respect, for example, names such as “first,” “second,” etc., generally indicate only the order in which relevant components are introduced into discussion and generally do not indicate or require a particular spatial arrangement, functional or structural preference or order.

[0102] As used herein, unless otherwise defined or limited, directional terms are used for ease of discussion with reference to a particular figure or example. For example, references to downward (or other) directions or top (or other) positions may be used to discuss aspects of a particular example or figure, but do not necessarily require similar orientations or geometries in all installations or constructions.

[0103] This discussion is presented to enable those skilled in the art to make and use examples of this disclosure. Various modifications to the illustrated examples will be apparent to those skilled in the art, and the general principles herein can be applied to other examples and applications without departing from the principles disclosed herein. Therefore, embodiments of this disclosure are not intended to be limited to the illustrated embodiments, but are to be given the widest scope consistent with the principles and features disclosed herein and the following claims. The following detailed description should be read with reference to the accompanying drawings, in which the same elements in the different drawings have the same reference numerals. These drawings, which are not necessarily drawn to scale, depict selected examples and are not intended to limit the scope of this disclosure. Those skilled in the art will recognize that the examples provided herein have many useful alternatives and fall within the scope of this disclosure.

[0104] The various features and advantages of this disclosure are set forth in the following claims.

Claims

1. A chain maintenance system, comprising: The inner chain links and the outer chain links each have corresponding pairs of openings; Pins, the pins comprising: Head end portion, the head end portion defining the head; The threaded end, opposite to the head end, has a thread; and A groove, which is introduced deeper into the surface of the pin than the thread of the pin, is located between the head end and the thread end; A multi-push bolt tensioner, comprising: Multiple fasteners; A pressure plate having a centrally positioned hole; and A plurality of other holes surrounding the centrally positioned hole, the plurality of other holes being threaded, each fastener being configured to receive and threadedly engage a corresponding hole among the plurality of other holes. The multi-push bolt tensioner is configured to engage the pin and is configured to be positioned externally relative to the outer chain link, and The multi-push bolt tensioner is configured to create an interference fit between the pin and the outer chain link at the orifice of the outer chain link.

2. The chain repair system according to claim 1, characterized in that, As the plurality of fasteners travel through the corresponding holes in their pressure plates and, with the pressure plates engaging the pins, the distance between the pressure plates and the outer chain links increases to force the pins through the holes.

3. The chain repair system according to claim 1, characterized in that, The pin includes another groove that is introduced deeper into the surface of the pin than the threads of the pin, the other groove being located between the head end and the threaded end, and The groove is introduced into one side of the pin, and the other groove is introduced into the opposite side of the pin.

4. The chain repair system according to claim 3, characterized in that, The groove and the other groove are each a V-shaped cut.

5. The chain repair system according to claim 1, characterized in that, The thread at the threaded end of the pin defines a first threaded section. The threaded end of the pin includes a second threaded section, and The groove is located between the first threaded section and the second threaded section.

6. The chain repair system according to claim 5, characterized in that, The groove of the pin defines a bridge portion that connects the first threaded section to the second threaded section. The width of the second threaded section is smaller than the width of the first threaded section, and The thickness of the bridge portion is less than the width of the second threaded section.

7. The chain repair system according to claim 5, characterized in that, The pin includes a peripheral flange extending around the pin, the peripheral flange being located between the first threaded section and the second threaded section.

8. The chain repair system according to claim 5, characterized in that, When the pin breaks at the groove, the first threaded portion of the pin disengages from the pin.

9. The chain repair system according to claim 8, characterized in that, The chain repair system also includes a nut configured to threadedly engage the first threaded portion of the pin, and The end of the nut is configured to contact the link of the outer chain.

10. The chain repair system according to claim 9, characterized in that, The nut is at least one of a locking nut or a self-locking nut.

11. The chain repair system according to claim 1, characterized in that, When each of the fasteners travels until each of the heads of each of the fasteners contacts the pressure plate, an interference fit is created between the pin and the outer chain link.

12. The chain repair system according to claim 1, characterized in that, When the interference fit is formed between the pin and the outer chain link, the inner chain link is configured to rotate around the pin.

13. The chain repair system according to claim 1, characterized in that, Also includes: Another inner chain link, the other inner chain link having another pair of orifices; Another pin; Another push bolt tensioner; The other pin is configured to receive an opening through the outer chain link and an opening through the other inner chain link; The other push bolt tensioner is configured to thread into the end of the other pin and force the other pin through another orifice of the outer chain link, thereby creating an interference fit between the other pin and the outer chain link at the other orifice.

14. The chain repair system according to claim 1, characterized in that, The pin also includes: A body having a first cross-section consistent along its entire length, wherein a head is attached to one end of the body, the cross-section of the head being larger than the first cross-section of the body; and An extension, connected to an opposite end of the body, the extension having threads including a first threaded segment and a second threaded segment, and the extension further having a groove located between the first threaded segment and the second threaded segment, the groove extending deeper into the surface of the pin than the threads of the first threaded segment and the second threaded segment of the pin. The body of the pin is configured to form an interference fit with the outer chain link at the orifice of the outer chain link to connect the outer chain link to the pin. The pin is configured to break at the groove, disengaging the first threaded section from the pin.

15. A method for repairing a chain, the method comprising: Align the holes of the outer chain links with the holes of the inner chain links; Insert the pin through the aligned hole, the pin having a threaded end opposite the head end; The multi-push bolt tensioner engages with the threaded end of the pin, the multi-push bolt tensioner having multiple fasteners; Each of the plurality of fasteners of the multi-push bolt tensioner is advanced and pressed onto the outer chain link; As the fastener moves, an interference fit is formed between the pin and the outer chain link at the opening of the outer chain link.

16. The method according to claim 15, characterized in that, It also includes breaking off at least a portion of the threaded end of the pin from the pin at the groove of the pin.

17. The method according to claim 16, characterized in that, Also includes: The threaded end of the pin is inserted into a hole passing through the outer chain link, the hole of the outer chain link partially defining the opening of the outer chain link; The threaded end of the pin is inserted into two holes passing through the inner chain link, the two holes of the inner chain link defining the opening of the inner chain link; The pressure plate of the multi-push bolt tensioner has a centrally positioned hole that engages with the threaded pin. The pressure plate has a plurality of other holes surrounding the centrally positioned hole, each of which is threaded. Each fastener is threadedly engaged with the corresponding hole in one of the plurality of other holes in the pressure plate; as well as Each of the plurality of fasteners is advanced and pressed onto the outer chain link so that the pressure plate is separated from the outer chain link.

18. The method according to claim 17, characterized in that, It also includes moving each of the plurality of fasteners in an alternating pattern to iteratively rotate and move the pressure plate.

19. The method according to claim 15, characterized in that, Also includes: Disconnect the multi-push bolt tensioner from the pin; as well as After the multi-push bolt tensioner is disengaged from the pin, a portion of the threaded end of the pin is broken off from the pin.

20. The method according to claim 19, characterized in that, It also includes threadedly engaging a nut with the pin after at least a portion of the threaded end of the pin has disengaged from the pin, until the nut contacts the outer chain link.

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