Cartridge seal assembly with semi-solid slurry filler and configured for mounting on fluid equipment

Abstract

A cartridge seal assembly configured to be mounted on an opening (27) of a housing (26) of a fluid device through which a rotating shaft (12) is inserted to prevent fluid (11) within the housing from escaping through the opening (27), the cartridge seal assembly (10) comprising a shaft sleeve (14), a retaining ring (16), a molded seal ring assembly (17), a semi-solid slurry filler (18), a cylindrical main stuffing box (20), an annular auxiliary stuffing box (22), a support frame (42), and one or more removable positioning blocks (34), all mounted around the rotating shaft (12), the main stuffing box (20) has a cylinder (20a) at its front end and a stepped portion (20b) at its rear end, the stepped portion (20b) extending outwardly relative to the cylinder (20a); the stepped portion (20b) is configured to be fixed to a rear end surface (26a) of the housing (26) surrounding the opening (27) while the cylinder (20a) passes through the opening (27), thereby forming a gap (29) between an outer peripheral surface of the cylinder (20a) and an inner wall surface (26c) of the housing (26) forming the opening (27) to allow the fluid (11) to flow therein; the cylinder (20a) has an inner peripheral surface surrounding an outer peripheral surface of the shaft sleeve (14) to form a cylindrical space into which the molded seal ring assembly (17) and the filler (18) are filled and in which the filler (18) is flowable; the stepped portion (20b) has a through hole (23) extending from an outer peripheral surface to an inner peripheral surface of the stepped portion (20b) to communicate with the cylindrical space, the through hole (23) having a portion forming a threaded joint (23a) located near the outer peripheral surface of the stepped portion (20b); the shaped sealing ring assembly (17) comprises a first shaped sealing ring (17a) and a second shaped sealing ring (17b) between which the filler (18) is located; the number of both the first molded sealing ring (17a) and the second molded sealing ring (17b) is at least one and / or both the first molded sealing ring (17a) and the second molded sealing ring (17b) are formed as separable components; the auxiliary stuffing box (22) is fixed to a rear end surface of the stepped portion (20b) by means of a biasing mechanism (28) so that a front end of the auxiliary stuffing box (22) projects axially forward from the rear end surface (26a) of the stepped portion (20b) into the cylindrical space and abuts against the second shaped sealing ring (17b); the support frame (42) comprises one or more axial rods (42c) arranged between the first shaped sealing ring (17a) and the second shaped sealing ring (17b) and suspended in the cylindrical space; the retaining ring (16) surrounds a rear end of the shaft sleeve (14) to secure the shaft sleeve (14) to the rotating shaft (12); the one or more removable positioning blocks (34) are configured to connect the retaining ring (16) to the auxiliary stuffing box (22) so that the cartridge sealing device (10) can be mounted around or removed from the rotating shaft (12) in one step, and are configured to be removable from the retaining ring (16) and the auxiliary stuffing box (22) so that the retaining ring (16) and the shaft sleeve (14) can rotate with the rotating shaft (12) during operation of the fluid device; the one or more axial rods (42c) are configured such that a distance between the first shaped sealing ring (17a) and the second shaped sealing ring (17b) can be varied between a minimum distance and a maximum distance; and the threaded connection (23a) is designed to be connected to an external injector to inject the filler (18) into the cylindrical space, thus increasing a sealing pressure formed in the cylindrical space, or to be blocked so that the sealing pressure can be adjusted by the biasing mechanism (28).

Description

Technical FieldThe present application relates to fluid equipment sealing technology and, more particularly, to a cartridge sealing device with a semi-solid slurry filler and configured for mounting on fluid equipment.Prior ArtIn industrial continuous production, a large amount of fluid (such as gas, a mixture of gas and liquid, and especially liquid) is transported by a pump or other fluid device. The pump generally consists of a housing and a rotating shaft. The rotating shaft passes through an opening of the housing and rotates at high speed to transport or pressurize the fluid in the housing during operation of the pump. Therefore, a seal means is mounted between the opening of the housing and the rotating shaft to prevent leakage of the fluid through the opening, thereby effectively and securely ensuring the operation of the pump. The sealing device may fail and must be replaced by shutting down the pump. Currently, the sealing means comprises a mechanical seal, a packing seal and a seal with a semi-solid slurry filler capable of forming a laminar shear flow. The mechanical seal is defined in relevant national standards as at least a pair of seal members whose end surfaces are perpendicular to a rotation axis and are held in sliding contact with each other under a pressure of a fluid and an elastic force or magnetic force of an assist mechanism to prevent leakage of the fluid.The mechanical seal, which comprises a sealing ring made of rigid material, has a good sealing effect, a long service life, but high processing requirements, a high price and a frequent need for maintenance. The packing seal includes a packing part that is plastically deformed by a fixing part and a rotating shaft to create a contact seal with the shaft. Since the packing member can be worn and at the same time the rotating shaft wears, the packing seal requires flushing water and leaks in small amounts, but is inexpensive and simple and convenient to maintain and replace. Chinese Patent Publication CN 114688073A discloses a packing seal in which a shaft sleeve for reducing the wear of a rotating shaft, a packing member and a packing gland are integrated into a cartridge to facilitate replacement. However, the packing seal must frequently be replaced due to the wear of the packing part.Chinese Utility Model CN201875137U and Chinese Utility Model CN215672853U disclose a gasket with a semi-solid slurry filler capable of forming a laminar shear flow. The seal described in Chinese utility model CN 215672853U can be used in a pump and has a cavity formed by two seal rings into which the filler is injected, and the filler is supported by a support frame to have a compressive strength. Thus, the seal does not wear a rotating shaft, does not require any flushing water, has no specification restrictions, can be maintained online, and can be easily mounted to a rotating shaft and a housing of the pump. However, since the laminar shear flow formed by the filler has a portion that wraps closely around and rotates with the rotating shaft during operation of the pump, during maintenance of the seal, it is necessary to damageally disassemble the seal to remove the portion completely from the rotating shaft and refill the filler after maintenance and replacement of other portions of the seal, which increases maintenance costs. Moreover, the present support frame can provide compressive strength only, but cannot prevent the filler from overheating, expanding, or even being lost, as measured as % Loss of Ignition (LOI), as a sealing pressure builds up in the cavity during injection of the filler.With the development of the modern industry, the mechanical seal has been gradually adopted for fluid appliances under better working conditions, while the packing seal or the seal with the semi-solid slurry filler capable of forming a laminar shear flow is still required for fluid appliances under poorer working conditions in which the fluid appliance contains a fluid with many impurities such as slurry or foreign particles. When these contaminants enter a seal surface between a rotating shaft and a packing member, wear of the rotating shaft and the packing member is increased, thereby impairing the sealing effect and significantly reducing the life of the seal and increasing the frequency of maintenance of the seal.Disclosure of the ApplicationIt is an object of the present application to provide an improved cartridge sealing apparatus with a semi-solid slurry filler and configured for mounting on fluid equipment.According to an aspect of the present application, there is provided a cartridge sealing device configured to be mounted on an opening of a housing of a fluid appliance through which a rotating shaft is inserted to prevent fluid within the housing from leaking through the opening, the cartridge sealing device comprising a shaft sleeve, a circlip, a shaped seal ring assembly, a semi-solid slurry filler, a cylindrical main gland, an auxiliary annular gland, a support frame and one or more removable positioning blocks all mounted around the rotating shaft, the main gland having a cylinder at its front end and a stepped portion at its rear end, the stepped portion extending outwardly relative to the cylinder; wherein the step-shaped portion is configured to be fixed to a rear end surface of the housing surrounding the opening while the cylinder passes through the opening, thereby forming a gap between an outer circumferential surface of the cylinder and an inner wall surface of the housing forming the opening for allowing the fluid to flow therein; wherein the cylinder has an inner circumferential surface surrounding an outer circumferential surface of the shaft sleeve to form a cylindrical space into which the molded seal ring assembly and the filler are filled and in which the filler is flowable; wherein the step-shaped portion has a through hole extending from an outer circumferential surface to an inner circumferential surface of the step-shaped portion to communicate with the cylindrical space, the through hole having a portion forming a threaded connection located near the outer circumferential surface of the step-shaped portion; wherein the shaped seal ring assembly comprises a first shaped seal ring and a second shaped seal ring between which the filler is located; wherein the number of each of the first shaped seal ring and the second shaped seal ring is at least one and / or each of the first shaped seal ring and the second shaped seal ring are formed as separable components; wherein the auxiliary gland is fixed to a rear end surface of the step-shaped portion by means of a biasing mechanism such that a front end of the auxiliary gland protrudes axially forward into the cylindrical space from the rear end surface of the step-shaped portion and abuts the second shaped seal ring; wherein the support frame comprises one or more axial rods disposed between the first shaped seal ring and the second shaped seal ring and suspended in the cylindrical space; wherein the retaining ring surrounds a rear end of the shaft sleeve to secure the shaft sleeve to the rotating shaft; wherein the one or more removable positioning blocks are configured to connect the retaining ring to the auxiliary gland such that the cartridge sealing device can be mounted around or removed from the rotating shaft in one step and are configured to be removable from the retaining ring and the auxiliary gland such that the retaining ring and the shaft sleeve can rotate with the rotating shaft during operation of the fluid device; wherein the one or more axial rods are configured such that a distance between the first shaped sealing ring and the second shaped sealing ring can be varied between a minimum distance and a maximum distance; and wherein the threaded connection is configured to be connected to an external injector to inject the filler into the cylindrical space, thereby increasing a sealing pressure formed in the cylindrical space, or to be blocked, such that the sealing pressure can be adjusted by the biasing mechanism.Optionally, the cartridge sealing device has an axial length from a front end surface of the first shaped sealing ring to a front end surface of the step-shaped portion that is more than twice an axial length from a rear end surface of the second shaped sealing ring to the front end surface of the step-shaped portion.Optionally, the cartridge sealing device further comprises an additional cylinder integrally formed with a front end of the cylinder, wherein an inner circumferential surface of the additional cylinder forms a helical groove, or wherein a front end surface of the additional cylinder forms a plurality of recesses radially spaced apart from each other and extending from an outer circumferential surface to an inner circumferential surface of the additional cylinder; and / or the cartridge sealing device further comprises an additional shaft sleeve integrally formed with a front end of the shaft sleeve, wherein an outer circumferential surface of the additional shaft sleeve forms a plurality of toothed rings axially spaced apart from each other, or wherein a front end surface of the additional shaft sleeve forms a plurality of recesses radially spaced apart from each other and extending from an outer circumferential surface to an inner circumferential surface of the additional shaft sleeve.Optionally, a start point of the spiral groove is located near or at the front end surface of the additional cylinder, and an end point of the spiral groove is located near or at a rear end surface of the additional cylinder and is separated from the cylindrical space, and a radial depth, an axial width, and / or a cross-sectional area of the spiral groove remain constant or gradually increase from the start point to the end point.Optionally, the plurality of toothed rings are separated from the cylindrical space and include straight teeth, oblique teeth, helical teeth, or a combination thereof.Optionally, the filler is a mixture of fibers and lubricant made from a mixture of solid powder and oil.Optionally, the support frame further comprises a first support ring abutting a rear end surface of the first shaped seal ring and a second support ring abutting a front end surface of the second shaped seal ring, and each of the one or more axial rods comprises a first tip, a first stop protruding relative to the first tip, a second tip, and a second stop protruding relative to the second tip, wherein the first tip is slidably inserted into the first support ring and the second tip is slidably inserted into the second support ring such that the first stop abuts the first support ring and the second stop abuts the second support ring when the minimum distance is reached.Optionally, the biasing mechanism comprises a bolt passing through a hole axially extending through the auxiliary gland and being screwed into a threaded hole formed at a rear end surface of the step-shaped portion, and a spring mounted around the bolt, wherein the auxiliary gland is fixed to the main gland by a biasing force provided by compressing the spring, wherein at the same time a gap may be present between a front end surface of a rear end of the auxiliary gland which does not protrude into the cylindrical space and the rear end surface of the step-shaped portion, such that the auxiliary gland can be axially displaced relative to the main gland, and wherein the spring is fully compressed when the maximum distance is reached.The cartridge sealing device provided in the present application can have improved reliability and safety, is easy to assemble and disassemble, eliminates a seal failure caused by artificial installation, is easy to disassemble and re-assemble during maintenance and repair of the fluid devices, solves the problem of short life and frequent failure of the sealing device under deteriorated working conditions where the fluid contains many contaminants, and can be widely used and cost-effectively used.Brief Description of the FiguresThe foregoing and other aspects of the present application will be more fully understood from the following detailed description relating to the drawings. FIG. 1 is a cartridge sealing device including a semi-solid slurry filler according to an embodiment of the present application before assembly between a rotating shaft and a housing of a fluid apparatus. FIG. 2 is a cross-sectional view of the apparatus of FIG. 1 after assembly between the rotating shaft and the housing. Fig. 3 is an end view of the apparatus of Fig. 1. FIG. 4 is a partial cross-sectional view of a portion of the apparatus of FIG. 1. FIG. 5 is a partial cross-sectional view of a portion of the apparatus of FIG. 4. FIG. 6 is a cross-sectional view of a cartridge sealing device with semi-solid slurry filler and configured for mounting to fluid devices according to an embodiment of the present application. FIG. 7 is a cross-sectional view of a support frame of the apparatus of FIG. 6. FIG. 8 is a cross-sectional view of a cartridge sealing device with semi-solid slurry filler and configured for mounting to fluid devices according to an embodiment of the present application. FIG. 9 is a cross-sectional view of a cartridge sealing device with semi-solid slurry filler and configured for mounting to fluid devices according to an embodiment of the present application. FIG. 10 is a cross-sectional view of a portion of a cartridge sealing device with semi-solid slurry filler and configured for mounting to fluid devices according to an embodiment of the present application. FIG. 11 is a cross-sectional view of a cartridge sealing device with semi-solid slurry filler and configured for mounting to fluid devices according to an embodiment of the present application. FIG. 12 is a cross-sectional view of a portion of a cartridge sealing device with semi-solid slurry filler and configured for mounting to fluid devices according to an embodiment of the present application.EmbodimentsVarious exemplary embodiments of the present disclosure will now be described in detail with reference to the drawings. Note that the relative arrangement of the components and steps, the numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present disclosure unless expressly stated otherwise.Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but may be part of the specification.The following description of one or more exemplary embodiments is intended for purposes of illustration only and is not intended to limit the present disclosure, its application, or uses. Thus, other example embodiments may include other values, structures, or features.It should be noted that the same reference numerals and letters refer to the same elements in the subsequent figures, so an element once defined in a figure cannot be discussed further in the subsequent figures.As shown in FIGS. 1 and 2, the application generally relates to a cartridge sealing device 10 configured to be mounted on an opening 27 of a housing 26 of a fluid device through which a rotating shaft 12 is inserted to prevent fluid 11 within the housing 26 from leaking through the opening 27. FIG. 1 is a cross-sectional view of the device 10 before assembly between the rotating shaft 12 and the housing 26, and FIG. 2 is a cross-sectional view of the device 10 after assembly between the rotating shaft 12 and the housing 26.In describing the apparatus 10, it is assumed that the apparatus 10 is mounted between the rotating shaft 12 and the housing 26. The terms "front" and "rear" are defined along an axis L of the device 10, wherein the term "front" is directed to a side that is axially proximate to the fluid 11 in the housing 26, and the term "rear" is directed to a side that is axially away from the fluid 11 in the housing 26. The terms "inner" and "outer" are defined perpendicular to the axis L, wherein the term "inner" is directed to a side that is radially close to the axis L, and the term "outer" is directed to a side that is radially away from the axis L.Generally, the apparatus 10 includes a shaft sleeve 14, a circlip 16, a shaped seal ring assembly 17, a semi-solid slurry filler 18, a cylindrical main gland 20, an auxiliary annular gland 22, a support frame 42, and one or more removable positioning blocks 34, all mounted about the rotating shaft 12. The support frame 42 is removed to clearly show the filler 18 in Figs. 1-2, 4, 8-9, and 11, and the filler 18 is removed to clearly show the support frame 42 in Fig. 6.The shaft sleeve 14 is made of a hard material including one of the following: metal, ceramic, alloy, silicon carbide, or a combination thereof.As shown in FIG. 1, the snap ring 16 surrounds a rear end of the shaft sleeve 14 to secure the shaft sleeve 14 to the rotating shaft 12. For example, one or more mounting screws may be threaded into one or more threaded holes 16a that extend radially through the snap ring 16 and pass through the rearward end of the shaft sleeve 14, thereby securing the shaft sleeve 14 to the rotating shaft 12. The shaft sleeve 14 therefore rotates with the rotating shaft 12, for example, the shaft sleeve 14 has an outer circumferential surface having a substantially constant diameter.The shaft sleeve 14 has a front end with an inner circumferential surface forming a groove 15 for receiving an elastic, e.g. O-shaped sealing ring 19 (as shown in Fig. 2) so as to provide a seal between the shaft sleeve 14 and the rotating shaft 12.As shown in FIG. 2, the main sleeve 20 has a cylinder 20a at its front end and a stepped portion 20b at its rear end which extends outward relative to the cylinder 20a.The step-shaped portion 20 bis configured to be fixed to a rear end surface 26 aof the housing 26 surrounding the opening 27, for example, via a washer 24 (e.g., a spacer or an elastic member made of fiber, rubber, etc.) and by one or more bolts 25, thereby forming a seal between the rear end surface 26 aof the housing 26 and the step-shaped portion 20 b(i.e., the main gland 20). The cylinder 20a extends axially through the opening 27 (as shown in Fig. 1), preferably axially beyond a front end surface 26b of the housing 26 surrounding the opening 27, thereby forming a gap 29 between an outer peripheral surface of the cylinder 20a and an inner wall surface 26c of the housing 26 forming the opening 27 for the fluid 11 to flow therein.The step-shaped portion 20 bhas an outer contour having a circular shape (as illustrated in FIG. 3 ), a waist shape, a drum shape, a square shape, and a wing shape that fits the housing 26.As shown in FIGS. 1 and 2, the cylinder 20 ahas a rear end connected to, for example, integrally formed with, the step-shaped portion 20 b. Optionally, a convex ring 20a1 is formed by the outer circumferential surface of the rear end of the cylinder 20a, which extends axially into the opening 27 and closes off the gap 29. The convex ring 20a1 has a substantially shorter axial length than the cylinder 20a and can be neglected.The cylinder 20a has an inner circumferential surface surrounding the outer circumferential surface of the shaft sleeve 14 to form a cylindrical space into which the molded seal ring assembly 17 and the filler 18 are filled. More specifically, the cylinder 20a has a stepped abutment portion 20a2 at its front end, the stepped abutment portion 20a2 extending inwardly relative to the inner circumferential surface of the cylinder 20a to form a clearance between the inner circumferential surface of the stepped abutment portion 20a2 and the outer circumferential surface of the shaft sleeve 14 for allowing the cylinder 20a (i.e., the main sleeve 20) to be fitted with clearance to the outer circumferential surface of the shaft sleeve 14. For example, the step-shaped portion 20 a 2 has a front end surface that can be radially aligned with a front end surface of the shaft sleeve 14 to achieve a compact structure.The molded seal ring assembly 17 includes a first molded seal ring 17a and a second molded seal ring 17b between which the filler 18 is interposed.For example, the number of each of the first shaped seal ring 17 aand the second shaped seal ring 17 bmay be at least one.In particular, when the shaped seal ring assembly 17 includes a plurality of first shaped seal rings 17 a, the plurality of first shaped seal rings 17 aare arranged in close axial proximity along the axis L. Similarly, when the shaped seal ring assembly 17 includes a plurality of second shaped seal rings 17 b, the plurality of second shaped seal rings 17 bare arranged in close axial alignment along the axis L.For example, both the first molded seal ring 17 aand the second molded seal ring 17 bmay be formed as separable components.In particular, the first shaped seal ring 17 aand / or the second shaped seal ring 17 bmay be split into a first shaped seal ring component and a second shaped seal ring component along its axial cross-section to facilitate assembly of the first shaped seal ring component and the second shaped seal ring component about the rotating shaft 12.As shown in FIG. 2, the device 10 has an axial length X from a front end surface of the first shaped seal ring 17a to a front end surface of the step-shaped portion 20b in the cylindrical space that is more than twice an axial length Y from a rear end surface of the second shaped seal ring 17b to a front end surface of the step-shaped portion 20b, thereby axially extending the gap 29.The auxiliary gland 22 has a rear end fixed to a rear end surface of the step-shaped portion 20b by means of a biasing mechanism 28 so that a front end of the auxiliary gland 22 axially protrudes forward into the cylindrical space and abuts against the second shaped seal ring 17b. In other words, the front end surface of the first shaped seal ring 17a abuts against the rear end surface of the step-shaped portion 20a2, the rear end surface of the second shaped seal ring 17b abuts against the front end of the auxiliary gland 22, an outer circumferential surface of the shaped seal ring assembly 17 abuts against the inner circumferential surface of the cylinder 20a, and an inner circumferential surface of the shaped seal ring assembly 17 abuts against the outer circumferential surface of the shaft sleeve 14.As shown in FIG. 4, the auxiliary gland 22 has an inner circumferential surface which is clearance-fitted with the outer circumferential surface of the shaft sleeve 14, the inner circumferential surface of the front end of the auxiliary gland 22 has a diameter larger than that of the inner circumferential surface of the rear end of the auxiliary gland 22, and the outer circumferential surface of the front end of the auxiliary gland 22 has a diameter smaller than that of the inner circumferential surface of the step-shaped portion 20b so that the front end of the auxiliary gland 22 smoothly protrudes into the cylindrical space as an axial protrusion. Thus, the molded seal ring assembly 17 and the filler 18 have an axial total length not greater than that of the cylindrical space, so that the second molded seal ring 17b would not axially protrude beyond the rear end of the step-shaped portion 20b.The shaped seal ring arrangement 17 may be a strip (also called packing) woven from soft fibers or made of rubber and having elastic and plastic properties.The filler 18 may consist of a mixture of fibers and lubricant made from a mixture of solid powder and oil.Optionally, the step-shaped portion 20 bincludes a through hole 23 extending from an outer circumferential surface to an inner circumferential surface of the step-shaped portion 20 bto communicate with the cylindrical space. The through hole 23 has an axis forming an angle of, for example, more than 60° with the axis L of the device 10, and a portion forming a threaded connection 23 aextending along the axis of the through hole 23 in the vicinity of the outer circumferential surface of the step-shaped portion 20 b. The threaded connection 23a may be blocked by a nut 25 when the device 10 is in normal operation. When the filler 18 is to be added, the nut 25 is removed from the threaded joint 23 ato connect an interface of an external injector (e.g., a filling gun) to the threaded joint 23 a, so that the filler 18 is injected into the cylindrical space by the external injector and is firmly pressed between the rear end surface of the first molded seal ring 17 aand the front end surface of the second molded seal ring 17 b. As a result, the sealing pressure arising in the cylindrical space is increased.As shown in detail in FIG. 5, the biasing mechanism 28 may include a bolt 30 having a head 30 aand a threaded rod, and a spring 32 mounted around the bolt 30. When the bolt 30 passes through a hole 21 axially extending through the auxiliary gland 22 and is screwed into a threaded hole axially extending into the rear end surface of the step-shaped portion 20b, one end of the spring 32 abuts against the head 30a and the other end of the spring 32 abuts against the rear end surface of the auxiliary gland 22 or the bottom of a recess 22a of the auxiliary gland 22, so that the auxiliary gland 22 is fixed to the main gland 20 by a biasing force generated by compression of the spring 32. Thus, the auxiliary gland 22 can be axially displaced relative to the main gland 20 by resisting the biasing force, and there may be a gap between a front end surface of the rear end of the auxiliary gland 22 which does not protrude into the cylindrical space and the rear end surface of the step-shaped portion 20b. It should be noted that the hole 21 of the auxiliary gland 22 has a diameter larger than that of the threaded rod and smaller than that of the head 30a. The spring 32 may be a Belleville spring which may provide a greater biasing force for a shorter stroke, or a helical spring (as shown in FIG. 5 ) which may provide a lesser biasing force for a longer stroke.On the one hand, the sealing pressure can be adjusted by the biasing mechanism 28 when the threaded connection 23 ais blocked by the nut 25. For example, when the bolt 30 is tightened, the biasing force applied to the molded seal ring assembly 17 and the filler 18 may be increased, and when the bolt 30 is loosened, the biasing force applied to the molded seal ring assembly 17 and the filler 18 may be decreased. In addition, the molded seal ring assembly 17 and the filler 18 can be taken out axially and replaced with a new molded seal ring assembly after the auxiliary gland 22 is removed from the step-shaped portion 20b, and then the filler 18 can be injected from the through hole 23 into the cylindrical space by the external injector after the auxiliary gland 22 is fixed to the step-shaped portion 20b.On the other hand, the biasing mechanism 28 may mitigate the effects of shocks and vibrations on the auxiliary gland 22.Specifically, when the filler 18 is injected into the cylindrical space, the sealing pressure in the cylindrical space largely increases and acts on the auxiliary gland 22 by opposing the biasing force, so that the auxiliary gland 22 moves axially away from the main gland 20. When the sealing pressure in the cylindrical space decreases, the auxiliary gland 22 can be axially displaced in the vicinity of the main gland 20. For example, during normal operation of the apparatus 10, the shaped seal ring assembly 17 may be worn so that the overall axial length of the shaped seal ring assembly 17 and the filler 18 decreases, and the auxiliary gland 22 may be axially displaced near the main gland 20 to accommodate the decrease in overall axial length until a front end surface of the front end of the auxiliary gland 22 contacts the rear end surface of the step portion 20b.As shown in FIG. 6 or back to FIGS. 2 and 3, the circlip 16 is rotatable relative to the one or more positioning blocks 34, and the device 10 may be integrated into a cartridge using the one or more positioning blocks 34, i.e., the shaft sleeve 14, circlip 16, shaped seal ring assembly 17, filler 18, main gland 20, and auxiliary gland 22 are packaged together such that the device 10 may be assembled around or removed from the rotating shaft 12 in one step.For example, the circlip 16 may be positioned axially relative to the shaft sleeve 14 by one or more positioning blocks 34. More specifically, the positioning block 34 includes a first portion 34 aand a second portion 34 bthat are at an angle, e.g., perpendicular, to each other, and one or more bolts 36 that extend axially through the first portion 34 aare used to attach the positioning block 34 to the rear end surface of the auxiliary gland 22. The first portion 34a has an axial length shorter than that of the auxiliary gland 22, and the first portion 34a has an axial length corresponding to the distance between the rear end surface of the auxiliary gland 22 and a front end surface of the snap ring 16. It should be noted that the auxiliary gland 22 is adjacent to the snap ring 16 to achieve a compact structure.The second portion 34 bincludes an annular groove 34 b 1 for receiving an outer periphery of the snap ring 16, or the snap ring 16 has an outer periphery forming an annular groove into which a radial protrusion formed by the outer periphery of the second portion 34 bmay be inserted, thereby preventing the snap ring 16 from moving axially relative to the shaft sleeve 14 while allowing the snap ring 16 to rotate relative to the shaft sleeve 14. After the apparatus 10 has been mounted around the rotating shaft 12 by means of the one or more fastening screws in one step with the one or more positioning blocks 34 and before the rotating shaft 12 rotates during operation of the fluid appliance, the one or more positioning blocks 34 are removed from the shaft sleeve 14. When the device 10 mounted about the rotating shaft 12 is to be removed in one step, the one or more positioning blocks 34 must be reassembled relative to the retaining ring 16 and the one or more mounting screws loosened.As shown in FIG. 6, the support frame 42 includes one or more axial rods 42 carranged between the first shaped seal ring 17 aand the second shaped seal ring 17 band suspended in the cylindrical space to assist the filler 18 to resist an excessive external pressure, e.g., the biasing force. The one or more axial rods 42 cmay be elastic. As shown in detail in FIG. 7, the support frame 42 further includes a first support ring 42 athat abuts against the rear end surface of the first shaped seal ring 17 aand a second support ring 42 bthat abuts against the front end surface of the second shaped seal ring 17 b. When there are a plurality of axial rods 42 c, the plurality of axial rods 42 cmay be evenly distributed around the peripheries of the first support ring 42 aand the second support ring 42 b. Each axial rod 42c has two axial ends connected to the first support ring 42a and the second support ring 42b, respectively. For example, each axial rod 42 cincludes a first tip 42 c 1, a first stopper 42 c 2 protruding relative to the first tip 42 c 1, a second tip 42 c 3, and a second stopper 42 c 4 protruding relative to the second tip 42 c 3. The first tip 42c1 is slidably inserted into a corresponding hole of the first support ring 42a, and the second tip 42c3 is slidably inserted into a corresponding hole of the second support ring 42b, so that a distance between the first molded seal ring 17a and the second molded seal ring 17b can be varied between a minimum distance and a maximum distance. When the distance is varied from the maximum distance to the minimum distance, the auxiliary gland 22 is axially displaced forward until the first stopper 42c2 abuts against the first support ring 42a and the second stopper 42c4 abuts against the second support ring 42b. As the distance is varied from the minimum distance to the maximum distance, the auxiliary gland 22 is axially displaced rearward until the spring 32 is fully compressed.The support frame 42 can maintain the minimum clearance even under excessive external pressure. At the same time, the support frame 42 allows the distance to be varied from the minimum distance to the maximum distance, thereby preventing the filler 18 from overheating, expanding or even being lost, measured as % Loss of Ignition (LOI) as the sealing pressure builds up in the cylindrical space during injection of the filler.In addition, the first back-up ring 42a has an inner diameter larger than that of the first molded seal ring 17a (i.e., the diameter of an inner circumferential surface of the first molded seal ring 17a) and an outer diameter smaller than that of the first molded seal ring 17a (i.e., the diameter of an outer circumferential surface of the first molded seal ring 17a).As shown in FIG. 8, when the one or more positioning blocks 34 are removed so that the shaft sleeve 14 rotates with the rotating shaft 12, the filler 18 is divided into a stationary portion 18 athat is engaged / attached / in contact with or in the vicinity of the inner circumferential surface of the cylinder 20 a, the rear end surface of the first shaped seal ring 17 a, and the front end surface of the second shaped seal ring 17 bto remain substantially stationary, and a rotating portion 18 b(for example, largely made of the fibers) that is slidably engaged / attached / in contact with the stationary portion 18 aand is wound or in the vicinity of the outer circumferential surface of the shaft sleeve 14 to rotate with the shaft sleeve 14.Optionally, each axial rod 42 cmay be closer to the inner circumferential surface of the cylinder 20 athan to the outer circumferential surface of the shaft sleeve 14 to avoid the rotating portion 18 bof the filler 18 so that the support frame 42 remains substantially stationary.When the rotating shaft 12 rotates, the rotating portion 18 bslides relative to the stationary portion 18 ato generate a large amount of heat. Nevertheless, the fluid 11, particularly liquid, may circulate into the gap 29 to bypass a major portion of the filler 18, thereby substantially cooling the filler 18.Optionally, as shown in FIG. 8, the apparatus 10 may include an additional cylinder 20 cintegrally formed with a front end of the cylinder 20 ato discharge contaminants, and having an inner circumferential surface forming a helical or spiral groove 38 whose rotational direction is the same as that of the rotating shaft 12 (e.g., clockwise). The spiral groove 38 extends along a spiral line with a spiral lead angle, has a starting point located near or at the front end surface of the additional cylinder 20c, and has an ending point located near or at a rear end surface of the additional cylinder 20c which can coincide with a front end surface of the cylinder 20a, i.e., the step-shaped portion 20a2, so that the spiral groove 38 is separated from the cylindrical space.The helical groove 38 has, for example, a radial depth, an axial width, and / or a cross-sectional area that remains constant or gradually increases from the starting point to the ending point.Generally, the radial depth is measured from a groove top 38 awith a smaller diameter to a groove bottom 38 bwith a larger diameter. The axial width is measured on a reference line parallel to an axis of the helical groove 38. The cross-sectional area is taken from an axial section of the spiral groove 38 and is calculated at least on the radial depth.As shown in FIG. 8, in a case where the radial depth gradually increases, the diameter of the groove bottom 38 bmay gradually increase from the starting point to the ending point, while the diameter of the groove top 38 amay be maintained substantially constant. Moreover, the groove top 38 amay have a minimum diameter that is smaller than the outer diameter of the shaft sleeve 14 (i.e., the diameter of the outer circumferential surface of the shaft sleeve 14) and larger than the inner diameter of the shaft sleeve 14 (i.e., the diameter of the inner circumferential surface of the shaft sleeve 14).As shown in FIG. 9, in a case where the radial depth gradually increases, the diameter of the groove top 38 amay gradually increase from the starting point to the ending point, while the diameter of the groove bottom 38 bmay be maintained substantially constant. Moreover, the groove top 38 amay have a minimum diameter that is greater than the outer diameter of the shaft sleeve 14.As the rotating shaft 12 rotates, the helical groove 38 remains stationary and cooperates with the rotating shaft 12 to prevent the fluid 11, particularly particulate contaminants in liquid, from entering the cylindrical space and damaging the seal between the shaft sleeve 14 and the main gland 20.Optionally, as shown in FIG. 10, the front end surface of the auxiliary cylinder 20 cis provided with a plurality of recesses 20 c 1 or teeth 20 c 2 radially and optionally equally spaced from each other and penetrating and / or extending from an outer circumferential surface of the auxiliary cylinder 20 cto an inner circumferential surface of the auxiliary cylinder 20 c. The plurality of recesses 20 c 1 or teeth 20 c 2 are separated from the cylindrical space. The plurality of recesses 20c1 or teeth 20c2 may be straight along an axis of the additional cylinder 20c coincident with the axis L of the device 10 (as shown in Fig. 10), inclined relative thereto and / or spiral about this axis.Optionally, as shown in Figure 11, the apparatus 10 comprises an additional shaft sleeve 14a integrally formed with a forward end of the shaft sleeve 14 to drain contaminants and having an outer circumferential surface with a plurality of toothed rings 40 axially spaced apart and functioning as a pump. The plurality of toothed rings 40 are separated from the cylindrical space and may include straight teeth, oblique teeth, helical teeth, or a combination thereof.Optionally, as shown in FIG. 12, the additional shaft sleeve 14 aincludes a front end surface provided with a plurality of recesses 14 a 1 or teeth 14 a 2 radially and optionally equally spaced from each other and penetrating and / or extending from an outer circumferential surface of the additional shaft sleeve 14 ato an inner circumferential surface of the additional shaft sleeve 14 a. The plurality of recesses 14 a 1 or teeth 14 a 2 are separated from the cylindrical space. The plurality of recesses 14 a 1 or teeth 14 a 2 may be straight along an axis of the additional shaft sleeve 14 a, which coincides with the axis L of the device 10 (as shown in FIG. 12 ), inclined relative thereto and / or spiral around this axis.As the rotating shaft 12 rotates, the shaft sleeve 14, and thus the toothed rings 40, rotate with the rotating shaft 12 to prevent the fluid 11, particularly the particulate contaminants in liquid, from entering the cylindrical space and damaging the seal between the shaft sleeve 14 and the main gland 20.Returning to Figure 9, if the particulate contaminants in liquid are excessive, the additional cylinder 20c and the additional shaft sleeve 14a may be combined with the helical groove 38 of the additional cylinder 20c being radially spaced from the toothed rings 40 of the additional shaft sleeve 14a. The additional cylinder 20 cmay have an axial length corresponding to that of the additional shaft sleeve 14 ain FIG. 9, but this is not necessarily required. It should be appreciated that the additional cylinder 20 cand the additional shaft sleeve 14 ahave various features that can be flexibly combined or separately implemented.Although some specific embodiments of the present disclosure have been illustrated in detail with examples by way of examples, it should be understood by those skilled in the art that the above examples are only for illustrative purposes but do not limit the scope of the present disclosure, and that the above embodiments may be modified without departing from the scope and spirit of the present disclosure.References included in the specificationThis list of documents cited by the applicant has been produced in an automated manner and is only included for the better information of the reader. The list is not part of the German patent application or utility model application. The DPMA does not take any adhesion for any faults or omissions.Patent Literature citedCN 114688073A

[0003] CN201875137U

[0004] CN 215672853U

[0004]

Claims

A cartridge sealing device configured to be mounted on an opening (27) of a housing (26) of a fluid appliance through which a rotating shaft (12) is inserted to prevent fluid (11) within the housing from exiting through the opening (27), the cartridge sealing device (10) comprising a shaft sleeve (14), a circlip (16), a shaped sealing ring arrangement (17), a semi-solid slurry filler (18), a cylindrical main gland (20), an annular auxiliary gland (22), a support frame (42) and one or more removable positioning blocks (34) all mounted around the rotating shaft (12), the main gland (20) having a cylinder (20a) at its front end and a step-shaped portion (20b) at its rear end, wherein the step-shaped portion (20b) extends outward relative to the cylinder (20a); the step-shaped portion (20b) is configured to be fixed to a rear end surface (26a) of the housing (26) surrounding the opening (27) while the cylinder (20a) passes through the opening (27), thereby forming a gap (29) between an outer circumferential surface of the cylinder (20a) and an inner wall surface (26c) of the housing (26) forming the opening (27) to allow the fluid (11) to flow therein; the cylinder (20a) has an inner circumferential surface surrounding an outer circumferential surface of the shaft sleeve (14) to form a cylindrical space into which the shaped seal ring assembly (17) and the filler (18) are filled and in which the filler (18) is flowable; the step-shaped portion (20b) has a through hole (23) extending from an outer circumferential surface to an inner circumferential surface of the step-shaped portion (20b) to communicate with the cylindrical space, the through hole (23) having a portion forming a threaded connection (23a) located near the outer circumferential surface of the step-shaped portion (20b); the shaped seal ring assembly (17) has a first shaped seal ring (17a) and a second shaped seal ring (17b) between which the filler (18) is located; the number of each of the first shaped seal ring (17a) and the second shaped seal ring (17b) is at least one; and / or each of the first shaped seal ring (17a) and the second shaped seal ring (17b) is formed as separable components; the auxiliary gland (22) is fixed to a rear end surface of the step-shaped portion (20b) by means of a biasing mechanism (28) such that a front end of the auxiliary gland (22) protrudes axially forward into the cylindrical space from the rear end surface (26a) of the step-shaped portion (20b) and abuts the second shaped seal ring (17b); the support frame (42) includes one or more axial rods (42c) disposed between the first shaped seal ring (17a) and the second shaped seal ring (17b) and suspended in the cylindrical space; the snap ring (16) surrounds a rear end of the shaft sleeve (14) to secure the shaft sleeve (14) to the rotating shaft (12); the one or more removable positioning blocks (34) configured to connect the circlip (16) to the auxiliary gland (22) such that the cartridge sealing device (10) can be mounted around or removed from the rotating shaft (12) in one step and configured to be removed from the circlip (16) and the auxiliary gland (22) such that the circlip (16) and the shaft sleeve (14) can rotate with the rotating shaft (12) during operation of the fluid appliance; the one or more axial rods (42c) configured such that a distance between the first shaped sealing ring (17a) and the second shaped sealing ring (17b) can be varied between a minimum distance and a maximum distance; and the threaded joint (23a) is configured to be connected to an external injector to inject the filler (18) into the cylindrical space, thus increasing a sealing pressure formed in the cylindrical space, or being blocked, so that the sealing pressure can be adjusted by the biasing mechanism (28).The cartridge sealing device (10) according to claim 1, characterized in that the cartridge sealing device (10) has an axial length (X) from a front end surface of the first molded seal ring (17a) to a front end surface of the step-shaped portion (20b) that is more than twice an axial length (Y) from a rear end surface of the second molded seal ring (17b) to the front end surface of the step-shaped portion (20b).The cartridge sealing device (10) according to claim 1, characterized in that the cartridge sealing device (10) further comprises an additional cylinder (20c) integrally formed with a front end of the cylinder (20a) and having an inner circumferential surface forming a spiral groove (38) or a front end surface forming a plurality of recesses radially spaced apart from each other and extending from an outer circumferential surface to an inner circumferential surface of the additional cylinder (20c); and / or the cartridge sealing device (10) further comprises an additional shaft sleeve (14a) integrally formed with a front end of the shaft sleeve (14) and having an outer circumferential surface forming a plurality of toothed rings axially spaced apart from each other or a front end surface forming a plurality of recesses radially spaced apart from each other and extending from an outer circumferential surface to an inner circumferential surface of the additional shaft sleeve (14a).The cartridge sealing device (10) according to claim 3, characterized in that the spiral groove (38) has a start point located near or at the front end surface of the auxiliary cylinder (20c) and an end point located near or at a rear end surface of the auxiliary cylinder (20c), and is separated from the cylindrical space, and has a radial depth, an axial width, and / or a cross-sectional area that remains constant or gradually increases from the start point to the end point.The cartridge sealing device (10) of claim 3, characterized in that the plurality of toothed rings are separated from the cylindrical space and comprise straight teeth, oblique teeth, helical teeth, or a combination thereof.Cartridge sealing device (10) according to claim 1, characterized in that the filler (18) consists of a mixture of fibers and lubricant, which is made of a mixture of solid powder and oil.The cartridge sealing device (10) of claim 1, characterized in that the support frame (42) further comprises a first support ring (42a) abutting a rear end surface of the first shaped seal ring (17a) and a second support ring (42b) abutting a front end surface of the second shaped seal ring (17b), and each of the one or more axial rods (42c) comprises a first tip (42c1), a first stopper (42c2) protruding relative to the first tip (42c1), a second tip (42c3), and a second stopper (42c4) protruding relative to the second tip (42c3), wherein the first tip (42c1) is slidably inserted into the first support ring (42a) and the second tip (42c3) is slidably inserted into the second support ring (42b), such that the first stop (42c2) abuts the first support ring (42a) and the second stop (42c4) abuts the second support ring (42b) when the minimum distance is reached.The cartridge sealing device (10) according to claim 7, characterized in that the biasing mechanism (28) comprises a bolt passing through a hole (21) axially extending through the auxiliary gland (22) and screwed into a threaded hole formed at a rear end surface of the step-shaped portion (20b), and a spring (32) mounted around the bolt, the auxiliary gland (22) being fixed to the main gland (20) by a biasing force provided by compressing the spring (32) so that the auxiliary gland (22) can be axially displaced relative to the main gland (20) by resisting the biasing force, and a gap between a front end surface of a rear end of the auxiliary gland (22) that does not protrude into the cylindrical space, and the rear end surface of the step portion (20b), and the spring (32) is fully compressed when the maximum distance is reached.

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