Removable packing gland assembly

Abstract

A packing gland assembly may include a packing gland housing defining an aperture extending from a front end to a rear end of the packing gland housing. The packing gland housing may include a flange having a front face defining a front end of the packing gland housing and a rear face. The flange may define a plurality of apertures extending from a front face of the flange to a rear face of the flange. The packing gland housing may include a mating neck extending from the flange to an aft end of the packing gland housing. The mating neck may define a stepped circumferential surface having one or more steps and may define a circumferential groove.

Description

Technical Field

[0001] The present invention generally relates to fluid pumps, and for example to removable packing gland assemblies. Background Technology

[0002] Hydraulic fracturing is a well enhancement technique that typically involves pumping fracturing fluid into the wellbore at a rate and pressure sufficient to create fractures in the rock formations surrounding the wellbore (e.g., up to 15,000 pounds per square inch (psi)). This well enhancement technique generally enhances the natural fracturing of rock formations to increase their permeability, thereby improving the recovery of water, oil, natural gas, and / or other fluids.

[0003] Positive displacement pumps are commonly used in high-pressure hydrocarbon recovery applications, such as injecting hydraulic fracturing fluids along the wellbore. A positive displacement pump typically has two parts: a power end and a fluid end. The power end includes a crankshaft driven by an engine or other power source, which drives the plunger on the fluid end. The fluid end includes a cylinder in which the plunger operates to allow fluid into a fluid chamber and then forces it out of the fluid chamber under high pressure to a discharge manifold that communicates with the wellhead fluid. A sealing assembly, also known as packing, packing assembly, or packing box, is provided in a packing orifice in the cylinder chamber to prevent fluid leakage from around the plunger during pumping operations. Over time, due to the applied high pressure and the reciprocating motion of the plunger, the packing orifice can become excessively worn, leading to leakage and / or failure. Repairing the packing orifice is quite difficult, and in cases of severe wear, the entire fluid end may need to be replaced.

[0004] The removable packing gland assembly of the present invention solves one or more of the problems mentioned above and / or other problems in the art. Summary of the Invention

[0005] A fluid end for a fluid pump may include a fluid end block defining a fluid chamber and a packing gland assembly. The packing gland assembly may include a packing gland housing that contacts the fluid chamber and defines an orifice extending from a front end to a rear end of the packing gland housing. The packing gland housing may include a flange having a front end and a rear end, the front end defining the front end of the packing gland housing. The flange may define a plurality of orifices extending from the front end to the rear end of the flange. The packing gland housing may include a mating neck extending from the flange to the rear end of the packing gland housing. The mating neck may define a stepped circumferential surface having one or more steps and may define a circumferential groove. The packing gland assembly may include a sealing ring disposed in the circumferential groove and a plurality of fasteners extending through the plurality of orifices and into the fluid end block to connect the packing gland housing to the fluid end block.

[0006] A packing gland assembly may include a packing gland housing defining an aperture extending from a front end to a rear end of the packing gland housing. The packing gland housing may include a flange having a front end and a rear end, the front end defining the front end of the packing gland housing. The flange may define a plurality of orifices extending from the front end to the rear end of the flange. The packing gland housing may include a mating neck extending from the flange to the rear end of the packing gland housing. The mating neck may define a stepped circumferential surface having one or more steps and may define a circumferential groove.

[0007] A fluid pump may include a power end and a fluid end coupled to the power end. The fluid end may include a fluid end block defining a fluid chamber and a packing gland assembly. The packing gland assembly may include a packing gland housing that contacts the fluid chamber and defines an orifice extending from a front end to a rear end of the packing gland housing. The packing gland housing may include a flange defining a plurality of orifices and a mating neck extending from the flange. The mating neck may define a stepped circumferential surface having one or more steps and may define a circumferential groove. The mating neck may have a face defining a rear end of the packing gland housing, and the face of the mating neck may directly abut the fluid end block. The packing gland assembly may include a sealing ring disposed in the circumferential groove and a plurality of fasteners extending through the plurality of orifices and into the fluid end block to connect the packing gland housing to the fluid end block. Attached Figure Description

[0008] Figure 1 This is a cross-sectional view of the fluid end of an exemplary prior art fluid pump.

[0009] Figure 2 This is a diagram showing a cross-sectional view of an exemplary fluid pump.

[0010] Figure 3 This is a perspective view showing an exemplary fluid end of a fluid pump.

[0011] Figure 4 This is a perspective view showing an exemplary packing gland housing.

[0012] Figure 5 This shows the section cut along line BB. Figure 4 The figure shows a cross-sectional view of the packing gland shell.

[0013] Figure 6 This is a diagram showing an enlarged cross-sectional view of the stepped circumferential surface of the mating neck.

[0014] Figure 7 This shows the section intercepted along line AA. Figure 3 A cross-sectional view of the fluid end.

[0015] Figure 8This is an enlarged cross-sectional view showing the connection between the fluid end block and the packing gland housing. Detailed Implementation

[0016] This invention relates to a removable packing gland assembly that is applicable to any reciprocating pump. For example, a reciprocating pump can be used in hydraulic fracturing applications.

[0017] Figure 1 This is a cross-sectional view of an exemplary prior art fluid end 100 of a fluid pump. Figure 1 The upper half of the cross-sectional view is shown; the lower half of the cross-sectional view may be the same as or similar to the upper half. As shown, the fluid end 100 includes a fluid cylinder 102, a packing gland 104 connected to the fluid cylinder 102 by one or more bolts 106, and a plunger 108 configured to reciprocate within the fluid cylinder 102 and the packing gland 104. The plunger 108 includes a plunger guide 110 and a plunger or short rod shoulder 112.

[0018] The packing includes a cage ring 114, a female connector 116, a PEek connector 118, a pressure ring 120, a manifold ring 122, and / or a steel gasket 124, which is disposed within a packing gland 104 surrounding a plunger 108. A packing nut 126 is secured to the inner surface of the packing gland 104 and holds the packing in place. A dust seal 128 is located between the packing nut 126 and the plunger 108. The packing gland 104 includes a lubricating oil or grease inlet 130 for lubricating the packing.

[0019] A sealing D-ring 132 is located between the packing gland 104 and the fluid cylinder 102 to seal the fluid in the fluid cylinder 102. A steel pressure ring 134 is located in the gap between the packing gland 104 and the fluid cylinder 102 to further seal the fluid in the fluid cylinder 102.

[0020] Figure 2 This is a cross-sectional view illustrating an exemplary fluid pump 200. In some embodiments, the fluid pump 200 may be mounted on a trailer to facilitate transport of the fluid pump 200 between multiple operating locations. As shown, the fluid pump 200 may be a reciprocating pump.

[0021] Fluid pump 200 includes a power end 202 and a fluid end 203 having a fluid end block 204. Fluid end 203 can be connected to power end 202 via a strut 206. Fluid end block 204 defines one or more fluid chambers 208 (only one is shown). For example, fluid pump 200 may include one, two, three, four, five, or more fluid chambers 208 and associated components. Fluid chambers 208 may sometimes be referred to as “orifices” of fluid pump 200.

[0022] Fluid pump 200 includes a suction valve 214 configured to control the intake of fluid into fluid chamber 208. Similarly, fluid pump 200 includes a discharge valve 216 configured to control the discharge of fluid from fluid chamber 208. During the suction stroke of plunger 220, fluid is allowed to flow from suction manifold 218 into fluid chamber 208 through suction valve 214. Fluid is then pumped in response to the discharge stroke (e.g., forward stroke) of plunger 220 and flows through discharge valve 216 into discharge port 212. Discharge port 212 can be fluidly coupled to a wellbore to supply high-pressure fluid for fracturing formations and other applications. In operation, reciprocating plunger 220 moves within plunger orifice 222 and is driven by power end 202 of fluid pump 200.

[0023] The power end 202 may include a crankshaft 224 rotated by a gearbox output 226 (shown as a single gear, but may be more than one gear). A gearbox input 228 is coupled to a transmission (not shown) and a power source (not shown), such as a diesel engine, to rotate the gearbox input 228 during operation. A connecting rod 230 mechanically connects the crankshaft 224 to a crosshead 232 via a piston pin end 234. The crosshead 232 is mounted within a fixed crosshead housing 236 that restricts the crosshead 232 to linear reciprocating motion. A short rod 238 is connected to the crosshead 232, and its opposite end is connected to a plunger 220 to enable the plunger 220 to reciprocate. The plunger 220 may be one of multiple plungers (e.g., three or five plungers), depending on the size of the fluid pump 200 (e.g., three-cylinder, five-cylinder, etc.) and the number of fluid chambers 208.

[0024] Plunger 220 extends through plunger bore 222 to engage with or extend within fluid chamber 208. In operation, movement of crankshaft 224 causes plunger 220 to reciprocate within fluid chamber 208, or to move linearly toward and away from fluid chamber 208. As plunger 220 translates away from fluid chamber 208 (during the suction stroke of plunger 220), the fluid pressure within fluid chamber 208 decreases, creating a pressure differential across suction valve 214. This pressure differential across suction valve 214 allows suction valve 214 to be actuated (e.g., opened) to allow fluid to enter fluid chamber 208 from suction manifold 218 (e.g., fluid is pressurized to a low pressure (e.g., 80 psi) by an external system (e.g., a centrifugal pump) and forced through suction manifold 218). As plunger 220 continues to translate away from fluid chamber 208, pumped fluid is pushed into fluid chamber 208. As plunger 220 changes direction and moves toward fluid chamber 208 (during the discharge stroke of plunger 220), the fluid pressure inside fluid chamber 208 increases, creating a pressure differential across discharge valve 216. As plunger 220 approaches fluid chamber 208, the fluid pressure inside fluid chamber 208 continues to increase until the pressure differential across discharge valve 216 becomes large enough to actuate (e.g., open) discharge valve 216 and allow fluid to exit fluid chamber 208.

[0025] The packing gland housing 240 is connected to the fluid end block 204, which is in contact with the fluid chamber 208. Packing 242 is disposed in a packing orifice of the packing gland housing 240 and surrounds a plunger 220 extending through the packing gland housing 240. A packing nut 244 is screwed into the packing gland housing 240 and is used to hold the packing 242 in proper position within the packing orifice. When properly positioned, the packing 242 and the packing nut 244 maintain the necessary pressure between the plunger 220 and the packing 242 and prevent leakage from the packing orifice. In some embodiments, a replaceable sleeve or bushing may be positioned in the packing orifice that contacts the packing 242.

[0026] As shown above, Figure 2 Provided as an example. Other examples may be found with reference to [the relevant information]. Figure 2 The descriptions are different.

[0027] Figure 3 This is a perspective view showing an exemplary fluid end 203 of a fluid pump 200. As shown, the fluid end 203 includes a fluid end block 204 and one or more packing gland assemblies 246 connected to the fluid end block 204. For example, as shown, five packing gland assemblies 246 may be connected to the fluid end block 204, one at each fluid chamber 208 of the fluid end block 204 (e.g., one at each cylinder). However, depending on the size of the fluid pump 200 (e.g., three-cylinder, five-cylinder, etc.) and the number of fluid chambers 208, the fluid end 203 may include a different number of packing gland assemblies 246 (e.g., three packing gland assemblies 246).

[0028] The packing gland assembly 246 may include a packing gland housing 240 and / or a packing nut 244 secured to (e.g., screwed into) the packing gland housing 240. A plurality of holes 248 may be positioned along the edge of the packing nut 244 for tightening or loosening the packing nut 244 relative to the packing gland housing 240. In some embodiments, the packing gland assembly 246 may include a nut lock 250 configured to engage with the packing nut 244 to restrict rotation of the packing nut 244. For example, the nut lock 250 may include an extendable pin that extends into a hole 248 in the packing nut 244 to rotate and lock the position of the packing nut 244.

[0029] The packing gland assembly 246 includes a plurality of fasteners 252 (e.g., a plurality of bolts) to connect (e.g., secure) the packing gland housing 240 to the fluid end block 204. In this way, the packing gland housing 240 can be removed from the fluid end block 204 for easy repair or replacement. Therefore, packing orifice failure can be addressed more effectively by removing the packing gland assembly 246 instead of replacing the entire fluid end 203. Furthermore, by using the removable packing gland assembly 246, a smaller initial block can be used to manufacture the fluid end block 204 compared to the original starting block used to manufacture the fluid end block with an integrated packing gland, resulting in significant material savings.

[0030] In some embodiments, the fluid end block 204 is made of a first material, and the packing gland housing 240 is made of a second material different from the first material. For example, the first material may be a first steel composition, and the second material may be a second steel composition. This can facilitate the simplification and low-cost manufacturing of the packing gland housing 240.

[0031] As shown above, Figure 3 Provided as an example. Other examples may be found with reference to [the relevant information]. Figure 3 The descriptions are different.

[0032] Figure 4 This is a perspective view illustrating an exemplary packing gland housing 240. The packing gland housing 240 defines an orifice 254. The orifice 254 extends from a front end 260 (e.g., a first end) to a rear end 262 (e.g., a second end) of the packing gland housing 240. The orifice 254 may define an inner circumferential surface and an outer circumferential surface of the packing gland housing 240 (e.g., the packing gland housing 240 may be annular). The orifice 254 may define a packing orifice (e.g., a place where packing is filled) and / or define at least a portion of a plunger orifice 222 of the packing gland housing 240.

[0033] As shown, the packing gland housing 240 includes a plurality of orifices 256 configured to receive corresponding fasteners 252. The orifices 256 may be located within the packing gland housing 240 surrounding orifices 254. In some embodiments, a port 258 is defined to extend through the packing gland housing 240 for introducing lubricating oil or grease into the orifices 254.

[0034] As shown above, Figure 4 Provided as an example. Other examples may be found with reference to [the relevant information]. Figure 4 The descriptions are different.

[0035] Figure 5 This shows the section cut along line BB. Figure 4 The figure shows a cross-sectional view of the packing gland housing 240. As shown, the packing gland housing 240 has a flange 264 and a mating neck 266 extending from the flange 264. The flange 264 and the mating neck 266 can be an integral unit.

[0036] Flange 264 may have an integral annular shape, or other shapes such as hexagonal or octagonal. Flange 264 has a front face 268 (e.g., a front annular face) and a rear face 270 (e.g., a rear annular face), with the front face 268 defining the front end 260 of the packing gland housing 240. The front face 268 and rear face 270 of flange 264 define the thickness of flange 264. Orifice 256 may be defined in flange 264, extending from the front face 268 to the rear face 270. Orifice 256 may be threaded to facilitate threaded engagement with fastener 252. In some examples, orifice 256 may include a countersunk portion and a threaded portion. The front face 268 of flange 264 also defines the front end 260 of packing gland housing 240, which imparts a considerable thickness to flange 264, reducing movement of packing gland housing 240 and improving the seal strength between packing gland housing 240 and fluid end block 204.

[0037] A mating neck 266 may extend from a flange 264 (e.g., from the rear end 270 of flange 264) to a rear end 262 of the packing gland housing. For example, a face 272 of the mating neck 266 may define a rear end 262 of the packing gland housing 240. The mating neck 266 is configured for insertion into a fluid end block 204 (e.g., such that the orifice 254 is aligned with the cylinder of the fluid end block 204). For this purpose, the mating neck 266 defines a stepped circumferential surface having one or more steps 274. Furthermore, the mating neck 266 defines a circumferential groove 276 configured to receive a sealing ring, as described herein. Steps 274 may be located between the circumferential groove 276 and the flange 264. In some embodiments, the mating neck 266 has at least two steps 274. For example, a first step 274 may project from the circumferential groove 276, and a second step 274 may extend from the rear end 270 of flange 264.

[0038] like Figure 5 As further shown, in some examples, the bore 254 may include multiple portions with different diameters. For example, in the first portion of the bore 254 (closest to the front end 260 of the packing gland housing 240), the inner circumferential surface of the packing gland housing 240 may be threaded to engage with threads on the packing nut 244. The second portion (middle portion) of the bore 254 may define a packing orifice (e.g., without threads) for filling packing. The third portion of the bore 254 (closest to the rear end 262 of the packing gland housing 240) may be narrower than the second portion to define a shoulder of the packing orifice on which packing can be stacked.

[0039] As shown above, Figure 5 Provided as an example. Other examples may be found with reference to [the relevant information]. Figure 5 The descriptions are different.

[0040] Figure 6 This is a schematic diagram showing an enlarged cross-sectional view of the stepped circumferential surface of the mating neck 266. As shown, one or more steps 274 may have a chamfer 278. For example, a step 274 extending from the rear end 270 of the flange 264 may have a chamfer 278. Additionally or alternatively, the leading edge of the face 272 of the mating neck 266 may have a chamfer 280. Chamfers 278 and 280 may have an aspect ratio of X:1, where X>1 or X>2. For example, chamfers 278 and 280 may have an aspect ratio of 3:1. Chamfers 278 and 280 facilitate the introduction of the mating neck 266 into the fluid end block 204.

[0041] As shown above, Figure 6 Provided as an example. Other examples may be found with reference to [the relevant information]. Figure 6 The descriptions are different.

[0042] As shown above, Figure 2 Provided as an example. Other examples may be found with reference to [the relevant information]. Figure 2 The descriptions are different.

[0043] Figure 7 This shows the section intercepted along line AA. Figure 3The figure shows a cross-sectional view of the fluid end 203. The fluid end 203 may include a stepped port 282 that receives a mating neck 266 of the packing gland housing 240. For example, the stepped port 282 mates with the stepped circumferential surface of the mating neck 266 (e.g., opposite). Thus, when the packing gland housing 240 is connected to the fluid end block 204, the mating neck 266 of the packing gland housing 240 is received in the stepped port 282 of the fluid end block 204, the flange 264 of the packing gland housing 240 abuts against the outer surface of the fluid end block 204, and the fastener 252 connects the packing gland housing 240 and the fluid end block 204.

[0044] As shown above, Figure 7 Provided as an example. Other examples may be found with reference to [the relevant information]. Figure 7 The descriptions are different.

[0045] Figure 8 This is an enlarged cross-sectional view showing the engagement between the fluid end block 204 and the packing gland housing 240. As shown, the face 272 of the mating neck 266 directly abuts the fluid end block 204 (e.g., without a pressure ring or gasket between them), thereby providing a flush engagement between the mating neck 266 and the fluid end block 204 that promotes fluid sealing. To facilitate the flush engagement between the faces 272 of the fluid end block 204 and the mating neck 266, one or more gaps 284 may be defined between the step 274 of the mating neck 266 and the stepped port 282 of the fluid end block 204. For example, the contours of the stepped port 282 of the fluid end block 204 and the contours of the mating neck 266 may be configured to define the gaps 284. As an example, the chamfers 278, 280 of the mating neck 266 and a similar chamfer 286 of the stepped port 282 (e.g., at the leading edge of the stepped port 282 and / or at the corner of one or more steps of the stepped port 282) can result in a gap 284. The gap 284 allows for operability between the fluid end block 204 and the packing gland housing 240 to ensure a tight fit at the interface between the mating neck 266 face 272 and the fluid end block 204.

[0046] As further shown, the packing gland assembly 246 may include a sealing ring 288 disposed in a circumferential groove 276. The sealing ring 288 provides an additional fluid seal between the packing gland housing 240 and the fluid end block 204. In some embodiments, the sealing ring 288 may have a raised central portion and raised edge portions, thereby defining a channel between a first raised edge portion and a raised central portion, and a channel between a second raised edge portion and a raised central portion.

[0047] As shown above, Figure 8 Provided as an example. Other examples may be found with reference to [the relevant information]. Figure 8The descriptions are different.

[0048] Industrial applicability

[0049] The packing gland assembly 246 described herein can be used in any fluid pump that uses a plunger to pressurize fluid. For example, the packing gland assembly 246 can be used in positive displacement pumps, such as reciprocating pumps. Specifically, the packing gland assembly 246 can be used in fluid pumps used in applications related to oil and gas extraction, such as hydraulic fracturing. The packing gland assembly 246 can be filled with packing surrounding the plunger to prevent fluid leakage from around the plunger during pumping operations. Generally, packing wears down adjacent surfaces, resulting in a “wash boarding” effect, which can lead to leaks and seal failures. These surfaces can also be worn down due to the high pressures applied within the fluid pump. When the packing gland is integrated with the fluid end block (e.g., as a single unit), it is difficult to repair worn surfaces, and the entire fluid end block is often replaced when repair is not possible.

[0050] The packing gland assembly 246 described herein can be removed from the fluid end block 204. For example, the fasteners 252 securing the packing gland housing 240 to the fluid end block 204 can be loosened to allow removal of the packing gland housing 240, making repair or replacement easier. Therefore, the fluid end block 204 does not need to be scrapped simply because of wear on the surfaces of the packing gland housing 240.

[0051] Furthermore, the packing gland assembly 246 described herein provides improved leak resistance. For example, the front face 268 of the flange 264 also defines the front end 260 of the packing gland housing 240, which imparts a considerable thickness to the flange 264, reducing movement of the packing gland housing 240 relative to the fluid end block 204 and improving the seal strength between the packing gland housing 240 and the fluid end block 204. Additionally, the stepped circumferential surface of the mating neck 266 and the chamfers 278, 280 define a gap 284 between the step 274 of the mating neck 266 and the stepped port 282 of the fluid end block 204, thereby allowing operability between the fluid end block 204 and the packing gland housing 240. This operability ensures a tight fit, with the face 272 of the mating neck 266 directly abutting the fluid end block 204, thereby improving fluid tightness and reducing leakage.

[0052] The foregoing disclosure provides examples and descriptions, but is not intended to be exhaustive or to limit the specific implementations to the precise forms disclosed. Modifications and variations may be made based on the foregoing disclosure, or may be derived from practice of specific implementations. Furthermore, any embodiments described herein may be combined unless the foregoing disclosure expressly provides for reasons why one or more embodiments cannot be combined. Even if specific combinations of features are recited in the claims and / or disclosed in the specification, these combinations are not intended to limit the disclosure of various embodiments. While each dependent claim listed below may directly depend on only one claim, the disclosure of various embodiments includes each dependent claim combined with each other claim in the group of claims.

[0053] As used herein, the terms “a,” “an,” and “a group” are intended to include one or more items and are interchangeable with “one or more.” Furthermore, as used herein, the article “described” is intended to include one or more items associated with the article “described” and is interchangeable with “described one or more.” Additionally, the phrase “based on” is intended to mean “at least partially based on,” unless otherwise explicitly stated. Moreover, as used herein, the term “or,” when used in series, is intended to be inclusive and is interchangeable with “and / or” unless otherwise explicitly stated (e.g., if used in combination with “any one” or “only one”). Furthermore, for ease of description, spatially relative terms such as “top” and “bottom” may be used herein to describe the relationship of one element or feature to another element or feature illustrated in the figures. In addition to the orientations depicted in the figures, spatially relative terms are intended to include different orientations of devices, apparatuses, and / or elements in use or operation. Devices may be oriented in other ways (rotated 90 degrees or otherwise), and the spatially relative descriptions used herein are interpreted accordingly.

Claims

1. A fluid end for a fluid pump, comprising: Fluid end block, which defines the fluid chamber; as well as The packing gland assembly includes: A packing gland housing, which is in contact with the fluid chamber, defines an aperture extending from a front end to a rear end of the packing gland housing, the packing gland housing comprising: A flange having a front and a rear, the front defining the front end of the packing gland housing. The flange defines a plurality of openings extending from the front of the flange to the rear of the flange; and The mating neck extends from the flange to the rear end of the packing gland housing, the mating neck defining a stepped circumferential surface with one or more steps, and defining a circumferential groove; A sealing ring, which is disposed in the circumferential groove; and Multiple fasteners, which pass through the multiple orifices and enter the fluid end block, connect the packing gland housing to the fluid end block.

2. The fluid end according to claim 1, wherein, The one or more steps are located between the circumferential groove and the flange.

3. The fluid end according to any one of claims 1 to 2, wherein, The mating neck has a face that defines the rear end of the packing gland housing, and, The surface of the mating neck directly abuts the fluid end block.

4. The fluid end according to any one of claims 1 to 3, wherein, One or more gaps are defined between the one or more steps and the fluid end block.

5. The fluid end according to any one of claims 1 to 4, wherein, The hole defines the inner and outer circumferential surfaces of the packing gland housing, and, The inner circumferential surface is threaded for engagement with the threads on the packing nut.

6. The fluid end according to any one of claims 1 to 5, wherein, The fluid end block is made of a first material, and the packing gland housing is made of a second material different from the first material.

7. A packing gland assembly, comprising: A packing gland housing defining an aperture extending from a front end to a rear end of the packing gland housing, the packing gland housing comprising: A flange having a front and a rear, the front defining the front end of the packing gland housing. The flange defines a plurality of openings extending from the front to the rear of the flange; and The mating neck extends from the flange to the rear end of the packing gland housing, the mating neck defining a stepped circumferential surface with one or more steps, and defining a circumferential groove.

8. The packing gland assembly according to claim 7, further comprising: A sealing ring is disposed in the circumferential groove.

9. The packing gland assembly according to any one of claims 7 to 8, wherein, At least one of the one or more steps has a chamfer.

10. The packing gland assembly according to any one of claims 7 to 9, wherein, The one or more steps include at least two steps.

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