A multi-lip seal ring for a plunger rod assembly and a plunger pump

Abstract

A multi-lip seal ring and a plunger pump for a plunger rod assembly, which relates to the technical field of seal rings. The plunger rod assembly includes: a plunger rod and a plunger seat, and the multi-lip seal ring includes: a seal ring inner sleeve, a seal ring outer sleeve and an elastic member; the seal ring inner sleeve is sleeved on the plunger rod and assembled with the plunger rod for sliding sealing, the seal ring inner sleeve is used to increase the sealing length between the plunger rod and store the wear debris generated when the plunger rod and the seal ring inner sleeve slide relative to each other; the seal ring outer sleeve is sleeved on the seal ring inner sleeve to protect the seal ring inner sleeve; the elastic member is arranged between the seal ring inner sleeve and the seal ring outer sleeve, and the elastic member is close to the side of the plunger seat, and the elastic member is used to lock the seal ring inner sleeve on the side close to the plunger seat to play a sealing role. The multi-lip seal ring adopting the above technical solution has the advantages of large sealing section area, good sealing effect, long service life, simple and ingenious structure.

Description

Technical Field

[0001] The invention relates to the technical field of sealing rings, and in particular to a multi-lip sealing ring for a plunger rod assembly and a plunger rod assembly and a plunger pump using the same. Background Art

[0002] As a common mechanical part, sealing rings are widely used in various industries, mainly to prevent liquid and gas leakage. The sealing ring used in the plunger rod assembly is mainly sleeved on the plunger rod, and can always maintain the sealing effect when the plunger rod and the sealing ring move relative to each other.

[0003] Most of the existing sealing rings used in plunger rod assemblies are made of PTFE (polytetrafluoroethylene) material, and have a spring steel wire structure embedded in the front end. Although it can play a good sealing role, the sealing length is short. When the existing sealing ring is used to seal strong acids, strong bases, volatile liquids, and liquids that are easy to crystallize when exposed to air, there are the following defects:

[0004] (1) The embedded stainless steel spring wire at the front end is easily corroded due to long-term immersion in highly corrosive liquids, resulting in reduced sealing performance;

[0005] (2) Since the sealing ring is mounted on the plunger rod and the sealing length is short, when the plunger rod returns, the highly corrosive liquid attached to its surface comes into contact with the air, which is prone to chemical reactions and crystallization, reducing the wear resistance and thus affecting the practical life.

[0006] Therefore, in view of the above problems, a sealing ring for a plunger rod with a long service life and good sealing effect is urgently needed. Summary of the invention

[0007] In view of the defects and shortcomings of the prior art, the first object of the present invention is to provide a multi-lip sealing ring for a plunger rod assembly, which contacts the plunger rod through the first lip portion and the second lip portion, fully extending the contact area between the multi-lip sealing ring and the plunger rod, thereby improving the sealing effect of the multi-lip sealing ring; and when the plunger rod assembly is working, it scrapes off the liquid attached to the plunger rod assembly through the first lip portion, thereby avoiding the sealed liquid from contacting the external air. At the same time, the accommodating cavity formed by the second lip portion and the first lip portion is used to accommodate the wear debris generated by the friction between the second lip portion and the plunger rod, thereby avoiding the wear debris from entering the sealed liquid. The multi-lip sealing ring has the advantages of large sealing section area, good sealing effect, long service life, and simple and ingenious structure.

[0008] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a multi-lip sealing ring for a plunger rod assembly, the plunger rod assembly comprising: a plunger rod and a plunger seat, the multi-lip sealing ring comprising: a sealing ring inner sleeve, a sealing ring outer sleeve and an elastic member; the sealing ring inner sleeve is sleeved on the plunger rod and assembled with the plunger rod for sliding sealing, the sealing ring inner sleeve is used to increase the sealing length between the plunger rod and store the wear debris generated when the plunger rod and the sealing ring inner sleeve slide relative to each other; the sealing ring outer sleeve is sleeved on the sealing ring inner sleeve to protect the sealing ring inner sleeve; the elastic member is arranged between the sealing ring inner sleeve and the sealing ring outer sleeve, and the elastic member is close to the plunger seat side, and the elastic member is used to lock the sealing ring inner sleeve on the side close to the plunger seat to play a sealing role.

[0009] The sealing ring inner sleeve comprises: an inner sleeve body; a first lip portion arranged on the inner sleeve body away from the elastic member and in contact with the plunger rod, wherein the first lip portion is used to scrape off residual liquid on the plunger rod when the plunger rod slides relative to the sealing ring; and a second lip portion arranged on the inner sleeve body close to the elastic member and in contact with the plunger rod, wherein the second lip portion and the first lip portion are arranged to form a receiving cavity, and the receiving cavity is used to collect wear debris generated by friction between the second lip portion and the plunger rod.

[0010] The first lip portion forms a first inner hole, the second lip portion forms a second inner hole, and the apertures of the first inner hole and the second inner hole are both smaller than the outer diameter of the plunger rod.

[0011] The inner wall of the first inner hole is a conical surface, and the inner diameter of the side close to the accommodating cavity is larger than the inner diameter of the side away from the accommodating cavity.

[0012] The inner wall of the second inner hole is a conical surface, and the inner diameter of the side close to the accommodating cavity is smaller than the inner diameter of the side away from the accommodating cavity.

[0013] The material of the inner sleeve of the sealing ring is an elastic plastic part, and the position on the second lip corresponding to the elastic part is recessed toward one side of the plunger rod under the elastic force of the elastic part.

[0014] The sealing ring outer shell is made of 304 stainless steel, the elastic member is an annular spring, and the elastic member is made of 316 stainless steel.

[0015] After adopting the above technical solution, the beneficial effects of the present invention are:

[0016] 1. The first lip part and the second lip part are in contact with the plunger rod, the elastic part seal is increased, the sealing length is increased, the contact area between the multi-lip seal ring and the plunger rod is fully extended, and crystallization caused by the contact between the liquid and the air is avoided, thereby improving the sealing effect of the multi-lip seal ring.

[0017] 2. The inner walls of the first inner hole and the second inner hole are both set to conical surfaces, so that the first lip portion (from left to right) and the second lip portion (from left to right) hold the plunger rod more tightly when the sealing pressure is greater, thereby achieving a good sealing effect at high pressure (5MPa).

[0018] 3. The liquid attached to the plunger rod assembly is scraped off by the first lip portion, thereby preventing the sealed liquid from contacting the external air. At the same time, the accommodating cavity formed by the second lip portion and the first lip portion is used to collect the wear debris generated by the friction between the second lip portion and the plunger rod, thereby preventing the wear debris from entering the sealed liquid. The sealing effect is good and the service life is long.

[0019] In view of the defects and shortcomings of the prior art, a second object of the present invention is to provide a plunger pump having the advantages of simple structure, ingenious design, long service life and good sealing effect.

[0020] To achieve the above object, the technical solution adopted by the present invention is: a plunger pump, comprising: a plunger rod assembly and a multi-lip sealing ring as described above and sleeved on the plunger rod.

[0021] After adopting the above technical scheme, the beneficial effect of the present invention is as follows: when the plunger rod assembly is working, the liquid attached to the plunger rod assembly is scraped off through the first lip portion, thereby avoiding the sealed liquid from contacting with the external air. At the same time, the accommodating cavity formed by the second lip portion and the first lip portion is used to accommodate the wear debris generated by the friction between the second lip portion and the plunger rod, thereby avoiding the wear debris from entering the sealed liquid, thereby improving the sealing effect of the plunger rod and extending the service life of the plunger rod. It has the advantages of simple structure, ingenious design, long service life and good sealing effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0023] Figure 1 It is a schematic diagram of the structure after cutting of this embodiment;

[0024] Figure 2 It corresponds to Figure 1 A magnified view of detail A;

[0025] Figure 3 Schematic diagram of the structure of the multi-lip sealing ring in this embodiment.

[0026] Explanation of the reference numerals: 1. plunger rod; 2. plunger seat; 3. sealing ring inner sleeve; 31. inner sleeve body; 32. first lip portion; 33. second lip portion; 4. sealing ring outer sleeve; 5. elastic member; 6. accommodating chamber. DETAILED DESCRIPTION

[0027] The present invention is further described in detail below in conjunction with the accompanying drawings.

[0028] This specific embodiment is only an explanation of the present invention, and it is not a limitation of the present invention. After reading this specification, those skilled in the art can make non-creative modifications to this embodiment as needed, but as long as it is within the scope of the claims of the present invention, it is protected by the patent law.

[0029] This embodiment relates to a multi-lip seal ring, such as Figure 1-3 As shown, the multi-lip seal ring is mainly used for the plunger rod assembly. Among them, the plunger rod 1 belongs to the prior art, and the plunger rod assembly includes: the plunger rod 1 and the plunger seat 2. It should be noted that the multi-lip seal ring is not limited to the plunger rod assembly, and it can also be used alone for other components that require sleeve sealing (for example, sealing columns, sealing plugs, etc.).

[0030] Specifically, Figure 1-3 As shown, the multi-lip seal ring includes: a seal ring inner sleeve 3, a seal ring outer sleeve 4 and an elastic member 5. Among them, the seal ring inner sleeve 3 is sleeved on the plunger rod 1, and is assembled with the plunger rod 1 in a sliding seal (that is, when the plunger rod 1 moves relative to the multi-lip seal ring, the plunger rod 1 and the seal ring always maintain a sealed state). The seal ring inner sleeve 3 is used to increase the sealing length between the plunger rod 1, thereby improving the sealing effect of the multi-lip seal ring. In addition, the seal ring inner sleeve 3 is also used to store the wear debris generated when the plunger rod 1 and the seal ring inner sleeve 3 slide relative to each other, thereby preventing the wear debris from entering the sealed liquid. The seal ring outer sleeve 4 is sleeved on the seal ring inner sleeve 3 to protect the seal ring inner sleeve 3. The elastic member 5 is arranged between the seal ring inner sleeve 3 and the seal ring outer sleeve 4, and the elastic member 5 is close to the side of the plunger seat 2 (that is, the right side). The elastic member 5 is used to lock the seal ring inner sleeve 3 on the side close to the plunger seat 2 to play a sealing role.

[0031] Furthermore, if Figure 1-3 As shown, the sealing ring inner sleeve 3 includes: an inner sleeve body 31 , a first lip portion 32 and a second lip portion 33 .

[0032] Specifically, Figure 1-3 As shown, the inner sleeve body 31 is sleeved with the sealing ring outer sleeve 4 through a stepped sleeve surface. The first lip portion 32 is arranged on the inner sleeve body 31 away from the elastic member 5 and in contact with the plunger rod 1. When the plunger rod 1 slides relative to the sealing ring, the first lip portion 32 is used to scrape off the liquid remaining on the plunger rod 1, thereby preventing the liquid attached to the plunger rod 1 from coming into contact with the air to produce a chemical reaction, reducing the wear resistance of the plunger rod 1 or the first lip, and thereby extending the service life of the multi-lip sealing ring. The second lip portion 33 is arranged on the inner sleeve body 31 close to the elastic member 5 and in contact with the plunger rod 1. The second lip portion 33 and the first lip portion 32 are surrounded by a accommodating chamber 6, which is used to collect the wear debris generated by the friction between the second lip portion 33 and the plunger rod 1.

[0033] Preferably, if Figure 1-3 As shown, the first lip portion 32 forms a first inner hole, the second lip portion 33 forms a second inner hole, and the diameters of the first inner hole and the second inner hole are both smaller than the outer diameter of the plunger rod 1. Thus, a good sealing effect is also achieved when the pressure value is small.

[0034] Furthermore, if Figure 1-3 As shown, the inner wall of the first inner hole is a conical surface, and the inner diameter of the side close to the accommodating cavity 6 is larger than the inner diameter of the side away from the accommodating cavity 6 (that is, the inner diameter of the inner wall of the first inner hole gradually increases from left to right). After the first inner hole is sleeved on the plunger rod 1, as the pressure increases, the plunger rod 1 is more tightly held, thereby playing a role of high-pressure (5MPa) sealing.

[0035] Furthermore, if Figure 1-3 As shown, the inner wall of the second inner hole is a conical surface, and the inner diameter of the side close to the accommodating chamber 6 is smaller than the inner diameter of the side away from the accommodating chamber 6. That is, the inner diameter of the inner wall of the first inner hole gradually increases from left to right). After the second inner hole is sleeved on the plunger rod 1, when the pressure increases, the plunger rod 1 is more tightly held, thereby playing a role of high-pressure (5MPa) sealing.

[0036] Preferably, if Figure 1-3 As shown, the material of the inner sleeve of the sealing ring is an elastic plastic part, and the position on the second lip portion 33 corresponding to the elastic part 5 holds the plunger rod 1 tightly under the elastic force of the elastic part 5, thereby improving the sealing effect of the multi-lip sealing ring.

[0037] Preferably, if Figure 1-3 As shown, the sealing ring jacket 4 is made of 304 stainless steel. The elastic member 5 is an annular spring, and the elastic member 5 is made of 316 stainless steel.

[0038] The working principle of this embodiment is roughly as follows: the first lip portion 32 and the second lip portion 33 are in contact with the plunger rod 1, so that the contact area between the multi-lip sealing ring and the plunger rod 1 is fully extended, thereby improving the sealing effect of the multi-lip sealing ring; and when the plunger rod assembly is working, it scrapes off the liquid attached to the plunger rod assembly through the first lip portion 32, thereby avoiding the sealed liquid from contacting the external air. At the same time, the accommodating cavity 6 formed by the second lip portion 33 and the first lip portion 32 is used to accommodate the wear debris generated by the friction between the second lip portion 33 and the plunger rod 1, thereby avoiding the wear debris from entering the sealed liquid. It has the advantages of large sealing section area, good sealing effect, long service life, and simple and ingenious structure.

[0039] Based on the above embodiment, this embodiment also provides a plunger pump, which includes: a plunger rod assembly and the multi-lip seal ring described in the above embodiment. The multi-lip seal ring is sleeved on the plunger rod 1 of the plunger rod assembly. The plunger pump adopting the above technical solution has the advantages of simple structure, ingenious design, long service life and good sealing effect.

[0040] The above is only used to illustrate the technical solution of the present invention rather than to limit it. Other modifications or equivalent substitutions made to the technical solution of the present invention by ordinary technicians in this field should be included in the scope of the claims of the present invention as long as they do not depart from the spirit and scope of the technical solution of the present invention.

Claims

1. A multi-lip seal ring for a plunger rod assembly, the plunger rod assembly comprising: A plunger rod (1) and a plunger seat (2), characterized in that the multi-lip sealing ring comprises: a sealing ring inner sleeve (3), a sealing ring outer sleeve (4) and an elastic member (5); The sealing ring inner sleeve (3) is sleeved on the plunger rod (1) and is assembled with the plunger rod (1) in a sliding and sealing manner. The sealing ring inner sleeve (3) is used to increase the sealing length between the plunger rod (1) and store wear debris generated when the plunger rod (1) and the sealing ring inner sleeve (3) slide relative to each other. The sealing ring outer sleeve (4) is sleeved on the sealing ring inner sleeve (3) to protect the sealing ring inner sleeve (3); the elastic member (5) is arranged between the sealing ring inner sleeve (3) and the sealing ring outer sleeve (4), and the elastic member (5) is close to one side of the plunger seat (2). The elastic member (5) is used to lock the sealing ring inner sleeve (3) on the side close to the plunger seat (2) to play a sealing role; The sealing ring inner sleeve (3) comprises: Inner sleeve body (31); a first lip portion (32) disposed on the inner sleeve body (31) at a side away from the elastic member (5) and in contact with the plunger rod (1), wherein when the plunger rod (1) slides relative to the sealing ring inner sleeve, the first lip portion (32) is used to scrape off liquid remaining on the plunger rod (1); and A second lip portion (33) is arranged on the inner sleeve body (31) near the elastic member (5) and in contact with the plunger rod (1). The second lip portion (33) and the first lip portion (32) are arranged to form a receiving cavity (6). The receiving cavity (6) is used to collect wear debris generated by friction between the second lip portion (33) and the plunger rod (1).

2. The multi-lip sealing ring according to claim 1, characterized in that: The first lip portion (32) forms a first inner hole, the second lip portion (33) forms a second inner hole, and the diameters of the first inner hole and the second inner hole are both smaller than the outer diameter of the plunger rod (1).

3. The multi-lip seal ring according to claim 2, characterized in that: The inner wall of the first inner hole is a conical surface, and the inner diameter of the side close to the accommodating cavity (6) is larger than the inner diameter of the side away from the accommodating cavity (6).

4. The multi-lip seal ring according to claim 2, characterized in that: The inner wall of the second inner hole is a conical surface, and the inner diameter of the side close to the accommodating cavity (6) is smaller than the inner diameter of the side away from the accommodating cavity (6).

5. The multi-lip seal ring according to claim 4, characterized in that: The material of the inner sleeve of the sealing ring is an elastic plastic part, and the position on the second lip portion (33) corresponding to the elastic part (5) tightly holds the plunger rod (1) under the elastic force of the elastic part (5).

6. The multi-lip seal ring according to claim 5, characterized in that: The sealing ring outer sleeve (4) is made of 304 stainless steel, the elastic member (5) is an annular spring, and the elastic member (5) is made of 316 stainless steel.

7. A plunger pump, characterized in that: include: A plunger rod assembly and a multi-lip sealing ring sleeved on the plunger rod (1) as claimed in any one of claims 1 to 6.

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