Improved stay bolt

Abstract

The utility model relates to the field of coal mill accessories, and particularly discloses an improved stay bolt which comprises a stepped shaft, a hexagonal groove and an external thread. A hexagonal groove is formed in one end of the stepped shaft, and a deep groove is formed in the other end. The stepped shaft is provided with an external thread; the stepped shaft is moved to enable the external threads to be aligned with the upper portion of the grinding roller of the coal mill for installation, then the plug is rotated to open the deep groove, lithium-based grease is injected into the deep groove through a tool, the lithium-based grease enters the external threads along the deep groove and the inlet and outlet hole, and therefore thread meshing of the external threads and the grinding roller of the coal mill is lubricated, abrasion of thread meshing is small, and the service life of the grinding roller is prolonged. The service life is long, an operator adds lithium-based grease outside the coal mill without dismounting the nut, and the problem that the thread is abraded due to the fact that the contact part of the thread and the barrel cannot be effectively lubricated in the process of adjusting the gap between grinding rollers for a long time in the existing bolt is solved, so that the gap between the stay bolt and the fixed nut is reduced, and the service life is prolonged. Therefore, the problem that the bolt is sheared by radial force instantly is solved.

Description

Technical Field

[0001] The utility model relates to the field of coal mill accessories, in particular to an improved pull rod bolt. Background Art

[0002] There are fixed roller limit tie rod bolts on the upper part of the medium-speed coal mill roller. The main function of the roller limit tie rod bolts is to adjust the gap between the roller and the grinding bowl liner. In the free state, the gap between the roller and the grinding bowl liner is 8-10mm. The tie rod bolts only bear the weight of the roller when the coal mill is unloaded.

[0003] The Chinese utility model patent with announcement number CN206001006U disclosed a tie rod sealing structure of a medium-speed coal mill on March 8, 2017, which relates to the field of coal mills and includes a cylinder body and a tie rod arranged on the cylinder body. The tie rod is provided with an upper sealing body and a lower sealing body. The upper sealing body includes a sealing member, which is arranged at the upper end of the tie rod. The lower end of the seal is provided with a conical groove, and a conical sleeve is provided in the conical groove. A skirt is provided on the outside of the seal, and a pressure plate is provided on the edge of the conical sleeve. The pressure plate is connected to the cylinder body by bolts. The lower sealing body includes a sealing box, which is connected to the cylinder body. A sealing packing is provided in the sealing box, and the sealing packing is in contact with the tie rod. The sealing member, the conical sleeve and the sealing packing are all made of rubber material. An air duct connected to the outside is provided on the sealing box, and a control valve is provided on the air duct. This design has a simple and reasonable structure and a tight seal, which avoids damage to the tie rod, eliminates the problem of leakage of the tie rod seal, and meets the requirements of the coal mill for the tie rod.

[0004] However, the above-mentioned disclosed scheme has the following shortcomings: only a sealing structure is used to seal the screw, so that the screw does not come into contact with coal ash and coal particles and cause wear during use; however, during long-term use, the contact area between the screw thread and the barrel cannot be effectively lubricated, resulting in wear of the thread, thereby reducing the clearance between the pull rod bolt and the fixing nut, resulting in instantaneous radial force shearing the bolt. Utility Model Content

[0005] The utility model aims to solve the technical problem that only a sealing structure is used to seal the screw, so that the screw does not come into contact with coal ash and coal particles and cause wear during use, but in long-term use, the contact part between the thread of the screw and the barrel cannot be effectively lubricated, resulting in wear of the thread, thereby reducing the gap between the tie rod bolt and the fixing nut, resulting in radial force shearing the bolt instantly, and provides an improved tie rod bolt.

[0006] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0007] The utility model describes an improved pull rod bolt, comprising a stepped shaft, a hexagonal groove and an external thread; a hexagonal groove is provided at one end of the stepped shaft and a deep groove is provided at the other end; an external thread is provided on the stepped shaft; an avoidance groove is provided on the stepped shaft corresponding to the external thread; a circular groove is provided on the stepped shaft corresponding to the external thread and the avoidance groove; an inlet and outlet hole is provided in the circular groove connected to the deep groove; an internal thread is provided at the end of the deep groove; a plug is inserted into the internal thread.

[0008] Furthermore, the stepped shaft and the plug are both made of cast iron.

[0009] Furthermore, the length of the external thread is equal to half of the stepped shaft.

[0010] Furthermore, the deep groove is filled with lithium-based grease.

[0011] Furthermore, the inlet and outlet holes pass through the axis of the stepped shaft.

[0012] The improved pull rod bolt provided by the utility model has the following beneficial effects:

[0013] 1. The utility model moves the stepped shaft so that the external thread is aligned with the upper part of the grinding roller of the coal mill for installation, then rotates the plug to open the deep groove, uses a tool to fill lithium-based grease into the deep groove, so that the lithium-based grease enters the external thread along the deep groove and the inlet and outlet holes, thereby lubricating the external thread and the thread engagement of the coal mill grinding roller, so that the wear of the thread engagement is small and the service life is long, and the operator can add lithium-based grease without disassembling the nut outside the coal mill, which solves the problem that the contact part between the thread and the cylinder of the existing bolt cannot be effectively lubricated during the long-term adjustment of the grinding roller gap, resulting in wear of the thread, thereby reducing the gap between the tie rod bolt and the fixed nut, resulting in the instantaneous radial force shearing of the bolt;

[0014] 2. The utility model fills the deep groove with lithium-based grease so that the lithium-based grease can enter the external thread along the deep groove and the inlet and outlet holes for lubrication, thereby lubricating the thread engagement of the external thread and the grinding roller of the coal mill, so that the wear of the thread engagement is small and the service life is long, and the operator can add lithium-based grease outside the coal mill without disassembling the nut, which solves the problem that the contact part between the thread and the cylinder of the existing bolt cannot be effectively lubricated during the long-term adjustment of the grinding roller gap, resulting in wear of the thread, thereby reducing the gap between the pull rod bolt and the fixing nut, resulting in the instantaneous occurrence of radial force shearing the bolt. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The specific implementation of the utility model is further described in detail below in conjunction with the accompanying drawings;

[0016] Figure 1 This is a first axonometric structural schematic diagram of the utility model;

[0017] Figure 2 It is a second axonometric structural schematic diagram of the utility model;

[0018] Figure 3 It is a schematic diagram of a quarter cross-section structure of the utility model.

[0019] Explanation of the numbers in the figure: 1. Stepped shaft; 2. Hexagonal groove; 3. External thread; 4. Avoidance groove; 5. Circular groove; 6. Entry and exit hole; 7. Deep groove; 8. Internal thread; 9. Plug. DETAILED DESCRIPTION

[0020] It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0021] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0022] It should be noted that all directional indications in the embodiments of the present invention (such as up-down-left-right-front-back...) are only used to explain the relative position relationship - movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly. The connection can be a direct connection or an indirect connection.

[0023] See also Figure 1-3As shown, an improved tie rod bolt comprises a stepped shaft 1, a hexagonal groove 2 and an external thread 3; the stepped shaft 1 is provided with a hexagonal groove 2 at one end and a deep groove 7 at the other end; the stepped shaft 1 is provided with an external thread 3; the stepped shaft 1 is provided with an avoidance groove 4 corresponding to the external thread 3; the stepped shaft 1 is provided with a circular groove 5 corresponding to the external thread 3 and the avoidance groove 4; the circular groove 5 is provided with an inlet and outlet hole 6 connected to the deep groove 7; the end of the deep groove 7 is provided with an internal thread 8; the internal thread 8 is threadedly plugged with a plug 9; when working, the external thread 3 is aligned with the upper part of the grinding roller of the coal mill by moving the stepped shaft 1 for installation Then rotate the plug 9 to open the deep groove 7, use a tool to fill lithium-based grease into the deep groove 7, so that the lithium-based grease enters the external thread 3 along the deep groove 7 and the inlet and outlet holes 6, thereby lubricating the external thread 3 and the thread engagement of the coal mill roller, so that the thread engagement has less wear and a long service life, and the operator can add lithium-based grease outside the coal mill without disassembling the nut, which solves the problem that the contact part between the thread and the cylinder body of the existing bolt cannot be effectively lubricated during the long-term adjustment of the grinding roller gap, resulting in wear of the thread, thereby reducing the gap between the pull rod bolt and the fixed nut, resulting in the instantaneous occurrence of radial force shear bolt problem.

[0024] The stepped shaft 1 and the plug 9 are both made of cast iron. When working, the stepped shaft 1 and the plug 9 made of cast iron have high structural strength and can be used stably.

[0025] The length of the external thread 3 is equal to half of the stepped shaft 1 .

[0026] The deep groove 7 is filled with lithium-based grease. During operation, the deep groove 7 is filled with lithium-based grease so that the lithium-based grease can flow along the deep groove 7 and the inlet and outlet holes 6 into the external thread 3 for lubrication, thereby lubricating the thread engagement of the external thread 3 and the grinding roller of the coal mill, so that the wear of the thread engagement is small and the service life is long. The operator can add lithium-based grease outside the coal mill without removing the nut, which solves the problem that the contact part between the thread and the cylinder of the existing bolt cannot be effectively lubricated during the long-term adjustment of the grinding roller gap, resulting in wear of the thread, thereby reducing the gap between the pull rod bolt and the fixing nut, resulting in the instantaneous occurrence of radial force shearing the bolt.

[0027] The inlet and outlet hole 6 passes through the axis of the stepped shaft 1; when working, the lithium-based grease in the deep groove 7 can be connected by passing through the axis of the stepped shaft 1 through the inlet and outlet hole 6, so that the lithium-based grease can be injected through the internal thread 8 and reach the external thread 3 along the deep groove 7 and the inlet and outlet hole 6, thereby lubricating the thread engagement of the external thread 3 and the grinding roller of the coal mill, so that the wear of the thread engagement is small and the service life is long, and the operator can add lithium-based grease outside the coal mill without removing the nut, which solves the problem that the contact part between the thread and the cylinder of the existing bolt cannot be effectively lubricated during the long-term adjustment of the grinding roller gap, resulting in wear of the thread, thereby reducing the gap between the pull rod bolt and the fixing nut, resulting in the instantaneous occurrence of radial force shear bolt problem.

[0028] The utility model adopts the above scheme, when in use, by moving the stepped shaft 1 so that the external thread 3 is aligned with the upper part of the grinding roller of the coal mill for installation, then rotating the plug 9 to open the deep groove 7, and using a tool to fill lithium-based grease into the deep groove 7, so that the lithium-based grease enters the external thread 3 along the deep groove 7 and the inlet and outlet holes 6, thereby lubricating the thread engagement of the external thread 3 and the grinding roller of the coal mill, so that the wear of the thread engagement is small and the service life is long, and the operator can add lithium-based grease without disassembling the nut outside the coal mill, which solves the problem that the contact part between the thread and the cylinder body of the existing bolt cannot be effectively lubricated during the long-term adjustment of the grinding roller gap, resulting in wear of the thread, thereby reducing the gap between the pull rod bolt and the fixed nut, resulting in the instantaneous radial force shearing of the bolt; the stepped shaft 1 and the plug 9 made of cast iron have high structural strength and can be used stably; by filling the deep groove 7 with lithium-based grease, the lithium-based grease can enter the external thread 3 along the deep groove 7 and the inlet and outlet holes 6 for lubrication, thereby lubricating the external thread 3 and the thread of the grinding roller of the coal mill. The meshing of the thread reduces the wear of the thread meshing and prolongs the service life. The operator can add lithium-based grease without removing the nut on the outside of the coal mill, which solves the problem that the contact part between the thread and the cylinder body cannot be effectively lubricated during the long-term adjustment of the gap between the grinding rollers of the existing bolts, resulting in wear of the thread, thereby reducing the gap between the pull rod bolt and the fixing nut, resulting in the problem of radial force shearing the bolt instantly; the lithium-based grease in the deep groove 7 can be connected by passing through the axis of the stepped shaft 1 through the inlet and outlet hole 6, so that the lithium-based grease can be injected through the internal thread 8 along the deep groove 7 and the inlet and outlet hole 6 to the external thread 3, thereby lubricating the thread meshing of the external thread 3 and the grinding roller of the coal mill, which reduces the wear of the thread meshing and prolongs the service life. The operator can add lithium-based grease without removing the nut on the outside of the coal mill, which solves the problem that the contact part between the thread and the cylinder body cannot be effectively lubricated during the long-term adjustment of the gap between the grinding rollers of the existing bolts, resulting in wear of the thread, thereby reducing the gap between the pull rod bolt and the fixing nut, resulting in the problem of radial force shearing the bolt instantly.

[0029] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0030] The above shows and describes the basic principle, main features and advantages of the utility model. Those skilled in the art should understand that the utility model is not limited by the above embodiments, and the above embodiments and descriptions are only for explaining the principle of the utility model. Without departing from the spirit and scope of the utility model, the utility model may have various changes and improvements, and these changes and improvements fall within the scope of the utility model to be protected.

Claims

1. An improved pull rod bolt, characterized in that; The invention comprises a stepped shaft (1), a hexagonal groove (2) and an external thread (3); one end of the stepped shaft (1) is provided with a hexagonal groove (2) and the other end is provided with a deep groove (7); the stepped shaft (1) is provided with an external thread (3); the stepped shaft (1) is provided with an avoidance groove (4) corresponding to the external thread (3); the stepped shaft (1) is provided with a circular groove (5) corresponding to the external thread (3) and the avoidance groove (4); an inlet and outlet hole (6) is provided in the circular groove (5) and connected to the deep groove (7); an internal thread (8) is provided at the end of the deep groove (7); a plug (9) is threadedly inserted into the internal thread (8).

2. The improved pull rod bolt according to claim 1, characterized in that: The stepped shaft (1) and the plug (9) are both made of cast iron.

3. The improved stay bolt according to claim 2, characterized in that: The length of the external thread (3) is equal to half of the stepped shaft (1).

4. The improved pull rod bolt according to claim 3, characterized in that: The deep groove (7) is filled with lithium-based grease.

5. The improved stay bolt according to claim 4, characterized in that: The inlet and outlet hole (6) passes through the axis of the stepped shaft (1).

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