Friction characteristic testing device for sealing ring under high-pressure working condition and using method

Abstract

The invention discloses a device for testing friction characteristics of a sealing ring under a high-pressure working condition, and the device is characterized in that the device comprises a high-pressure air supply device, a tested device, a traction device, a power device, a balancing device, a low-pressure air supply device, a displacement sensor, a tension and pressure sensor, and a rack; one end of the tested device is connected with the high-pressure air supply device, and the other end of the tested device is connected with the traction device; one end of the balancing device is connected with the low-pressure air supply device, and the other end is connected with the traction device; the power device is mechanically fixed on the rack and is vertically connected with the traction device through the tension and pressure sensor; the displacement sensor is fixed on the rack and is used for measuring the displacement change of the traction device in real time; and the tension and pressure sensor measures the applied driving force in real time. According to the invention, friction characteristic tests of different types of sealing rings under different pressure working conditions can be carried out; by adopting the air bearing, the test error is reduced; and data support is provided for sealing ring selection, high-pressure sealing design, friction parameter identification and the like.

Description

Technical Field

[0001] The invention belongs to the field of sealing ring friction force measurement, and in particular relates to a sealing ring friction characteristic testing device under high pressure working conditions and a use method. Background Art

[0002] The sealing ring is a commonly used sealing component that relies on extrusion deformation to achieve sealing of gases, liquids, etc. Its friction characteristics have an important influence on the reliability and service life of the seal, as well as the movement efficiency and control accuracy of the mechanism.

[0003] Under high pressure, the friction characteristics of the sealing ring in different motion states of the contact element cannot be obtained through existing calculation methods, and ordinary friction force measurement devices are difficult to achieve high pressure conditions, and the test results have large errors. Therefore, a device that can simulate the high-pressure working environment of the sealing ring to test the friction characteristics is needed to provide data support for the selection of sealing rings, high-pressure seal design, friction parameter identification, and driver design. Summary of the invention

[0004] In order to solve the above problems, the present invention proposes a friction characteristic test device for a sealing ring under high pressure conditions, which includes a high-pressure air supply device, a device to be tested, a pulling device, a power device, a balancing device, a low-pressure air supply device, a displacement sensor, a tension pressure sensor, and a test stand:

[0005] The high-pressure gas supply device includes a high-pressure stabilizing tank and a high-pressure air inlet pipe. The high-pressure gas first enters the high-pressure stabilizing tank before entering the device under test, so that the pressure is more stable.

[0006] The device under test comprises a pressure sensor 1, a front end cover, a cylinder barrel, an end cover connecting rod, a rear end cover, a push rod, a universal joint 1, a base of the device under test, and a frictionless guide ring;

[0007] The front end cover and the rear end cover are fixed to the base of the device under test by screws; the cylinder barrel is installed between the front end cover and the rear end cover and fastened by four end cover connecting rods; the other side of the front end cover is connected to the high-pressure intake pipe, and a pressure sensor is installed on the top to measure the intake pressure in real time; a guide ring is installed on the other side of the rear end cover, and a through hole is opened on the top; the push rod extends from the rear end cover into the cylinder barrel through a frictionless guide ring; a sealing groove is opened at one end of the push rod for installing the tested sealing ring; a universal joint is installed on the other end of the push rod, and is connected to the pulling device through the universal joint.

[0008] The pulling device includes a pulling device base, an air bearing 1, a main shaft, a connecting plate, an air bearing 2, a hydraulic buffer device 1, a balance rod, an air bearing 3, and a hydraulic buffer device 2; the air bearing 1 and the air bearing 2 are fixed to the pulling device base by screws to support the main shaft to float; the balance rod is fixed to the pulling device base and installed parallel to the main shaft; the connecting plate is perpendicular to the main shaft and the balance rod, one end is fixed to the main shaft by bolts, and the other end is installed with the air bearing 3; the air bearing 3 passes through the balance rod and can move frictionlessly along the balance rod; limit baffles are installed at both ends of the main shaft, which are respectively connected to the universal joint 1 and the universal joint 2; the hydraulic buffer device 1 and the hydraulic buffer device 2 play an anti-collision and buffering role.

[0009] The power device is equipped with a booster rod; the booster rod is parallel to the balance rod and vertically connected to the connecting plate through a tension and pressure sensor; when the power device is driven to make the booster rod move forward and backward, the connecting plate and the main shaft can be driven to move together, and the tension and pressure sensor measures the applied driving force in real time.

[0010] The balancing device includes universal joint 2, cylinder rod, air-floating frictionless cylinder, pressure sensor 2, cylinder base 1 and cylinder base 2; the cylinder base 1 and cylinder base 2 are installed on the bench; the air-floating frictionless cylinder is fixed on the bench through cylinder base 1 and cylinder base 2, one end of which extends out of the cylinder rod and is connected to the main shaft through universal joint 2, and the other end is connected to the low-pressure air supply device; the pressure sensor 2 is installed above the air-floating frictionless cylinder to measure the intake pressure in real time.

[0011] The low-pressure air supply device comprises a low-pressure air inlet pipe and a low-pressure stabilizing tank, which provide a stable air source for the air-floating frictionless cylinder.

[0012] The cylinder barrel, push rod, main shaft and cylinder rod are on the same axis, parallel to the axis of the balance rod and the booster rod and at the same height; the frictionless guide ring, universal joint 1, universal joint 2 and balance rod play a role in correcting deviation;

[0013] The displacement sensor is fixed on the bench and measures the displacement change of the connecting plate in real time, thereby obtaining the movement state of the ejector rod and the measured sealing ring.

[0014] The method for using the friction characteristics testing device of the sealing ring under high pressure conditions is as follows:

[0015] Use a high-pressure air supply device to inflate the cylinder, and the push rod and the tested sealing ring form a sealed space in the cylinder. The pressure sensor measures the pressure P1 there. Assuming that the direction of the push rod moving toward the front cover is positive, the pneumatic load F1 on the push rod and the tested sealing ring can be calculated from the cylinder ventilation area A1 = -P1·A1;

[0016] The low-pressure air supply device inflates the air-floating frictionless cylinder to make the cylinder rod, main shaft and push rod close to the equilibrium state. The second pressure sensor measures the pressure P2 there. The balancing force F2 provided by the air-floating frictionless cylinder can be calculated from the ventilation area A2 of the air-floating frictionless cylinder.

[0017] The power device drives the force rod to apply force to the main shaft through the connecting plate, driving the push rod and the tested sealing ring to move back and forth in the cylinder, and the tension pressure sensor measures the force F3 in real time;

[0018] According to the measurement results of the displacement sensor, the movement velocity v and acceleration a of the connecting plate are derived;

[0019] Consider the ejector rod, universal joint 1, main shaft, connecting plate, universal joint 2, cylinder rod, etc. as a whole with a mass of m. According to Newton's law of motion, the friction force F of the tested seal ring in this motion state is obtained. f =ma-(F1+F2+F3).

[0020] The present invention adopts the combination of a cylinder barrel, a push rod and a sealing groove, and can test sealing rings of different pressure states, different sizes and different materials; adopts a pulling device and a balancing device, and can realize friction testing under high pressure and atmospheric dynamic load conditions, thereby improving the pressure conditions of the existing testing device; adopts an air-floating bearing, and reduces the system error; adopts a displacement sensor, a pressure sensor and a tension pressure sensor, and can obtain the friction characteristics of the sealing ring under different motion states such as static and dynamic.

[0021] The beneficial effects of the present invention compared with the prior art are:

[0022] (1) The present invention adopts the combination of the cylinder barrel, the ejector rod and the sealing groove to form a sealing space with sealing rings of different sizes and materials, and to test the friction characteristics of sealing rings of different models under different pressure conditions;

[0023] (2) The present invention adopts a balancing device and a low-pressure air supply device, which can offset the aerodynamic load on the tested sealing ring and the ejector rod under high-pressure working conditions, thereby reducing the requirements for the power device;

[0024] (3) The present invention adopts a pulling device and a balancing device to improve the pressure working condition of the existing testing device, and adopts an air bearing to reduce the test error;

[0025] (4) The present invention adopts displacement sensors, pressure sensors, and tension and pressure sensors to obtain the friction characteristics of the sealing ring under different motion states such as static and dynamic, and provide data support for the selection of sealing rings, high-pressure seal design, friction parameter identification, and driver design. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] 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 some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0027] Figure 1 An overall schematic diagram of a friction characteristic testing device for a sealing ring under high pressure conditions provided by an embodiment of the present invention;

[0028] Figure 2 A three-dimensional exploded view of a device under test provided by an embodiment of the present invention;

[0029] Figure 3 A schematic diagram of a pulling device provided in an embodiment of the present invention;

[0030] Figure 4 A schematic diagram of a balancing device provided in an embodiment of the present invention;

[0031] In the figure: 1 is a high-pressure air supply device; 2 is a device to be tested; 3 is a pulling device; 4 is a power device; 5 is a balancing device; 6 is a low-pressure air supply device; 7 is a displacement sensor; 8 is a tension pressure sensor; 9 is a stand; 11 is a high-pressure stabilizer tank; 12 is a high-pressure air intake pipe; 21 is a pressure sensor 1; 22 is a front cover; 23 is a cylinder barrel; 24 is an end cover connecting rod; 25 is a rear cover; 26 is a push rod; 27 is a universal joint 1; 28 is a base of the device to be tested; 29 is a frictionless guide The axial direction is as follows: 31 is the pulling device base; 32 is the air bearing 1; 33 is the main shaft; 34 is the connecting plate; 35 is the air bearing 2; 36 is the hydraulic buffer device 1; 37 is the balance rod; 38 is the air bearing 3; 39 is the hydraulic buffer device 2; 41 is the booster rod; 51 is the universal joint 2; 52 is the cylinder rod; 53 is the floating frictionless cylinder; 54 is the pressure sensor 2; 55 is the cylinder base 1; 56 is the cylinder base 2; 61 is the low-pressure air inlet pipe; 62 is the low-pressure stabilizing tank.

[0032] Specific implementation methods

[0033] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0034] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention, and thus the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0035] A device for testing the friction characteristics of a sealing ring under high-pressure working conditions, comprising a high-pressure air supply device 1, a device to be tested 2, a pulling device 3, a power device 4, a balancing device 5, a low-pressure air supply device 6, a displacement sensor 7, a pulling pressure sensor 8, and a stand 9; one end of the device to be tested 2 is connected to the high-pressure air supply device 1, and the other end is connected to the pulling device 3; one end of the balancing device 5 is connected to the low-pressure air supply device 6, and the other end is connected to the pulling device 3; the power device 4 is mechanically fixed on the stand 9, and is vertically connected to the pulling device 3 through the pulling pressure sensor 8; the displacement sensor 7 is fixed on the stand 9 to measure the displacement change of the pulling device 3 in real time.

[0036] The high-pressure gas supply device 1 includes a high-pressure stabilizing tank 11 and a high-pressure air inlet pipe 12. The high-pressure gas first enters the high-pressure stabilizing tank 11 before entering the device under test 2, so that the pressure is more stable.

[0037] The device under test 2 comprises a pressure sensor 21, a front end cover 22, a cylinder 23, an end cover connecting rod 24, a rear end cover 25, a push rod 26, a universal joint 27, a device under test base 28, and a frictionless guide ring 29;

[0038] The front end cover 22 and the rear end cover 25 are fixed to the base 28 of the device under test by screws; the cylinder barrel 23 is installed between the front end cover 22 and the rear end cover 25, and is fastened by four end cover connecting rods 24; the other side of the front end cover 22 is connected to the high-pressure intake pipe 12, and a pressure sensor 21 is installed on the top to measure the intake pressure in real time; a guide ring 29 is installed on the other side of the rear end cover 25, and a through hole is opened on the top; the push rod 26 extends from the rear end cover 25 into the cylinder barrel 23 through the frictionless guide ring 29; a sealing groove is opened at one end of the push rod 26 for installing the tested sealing ring; a universal joint 27 is installed on the other end of the push rod 26, and is connected to the pulling device 3 through the universal joint 27.

[0039] The pulling device 3 includes a pulling device base 31, an air bearing 1 32, a main shaft 33, a connecting plate 34, an air bearing 2 35, a hydraulic buffer device 1 36, a balance bar 37, an air bearing 38, and a hydraulic buffer device 2 39; the air bearing 1 32 and the air bearing 2 35 are fixed to the pulling device base 31 by screws to support the main shaft 33 to float; the balance bar 37 is fixed to the pulling device base 31 and installed parallel to the main shaft 33; the connecting plate 34 is perpendicular to the main shaft 33 and the balance bar 37, one end is fixedly connected to the main shaft 33 by bolts, and the other end is installed with an air bearing 3 38; the air bearing 3 38 passes through the balance bar 37 and can move frictionlessly along the balance bar 37; limit baffles are installed at both ends of the main shaft 33, which are respectively connected to the universal joint 1 27 and the universal joint 2 51; the hydraulic buffer device 1 36 and the hydraulic buffer device 2 39 play an anti-collision and buffering role.

[0040] The power device 4 is equipped with a boost rod 41; the boost rod 41 is parallel to the balance rod 37 and vertically connected to the connecting plate 34 through the tension pressure sensor 8; when the power device 4 is driven to make the boost rod 41 move forward and backward, the connecting plate 34 and the main shaft 33 can be driven to move together.

[0041] The balancing device 5 includes a universal joint 2 51, a cylinder rod 52, an air-floating frictionless cylinder 53, a pressure sensor 2 54, a cylinder base 1 55, and a cylinder base 2 56; the cylinder base 1 55 and the cylinder base 2 56 are installed on the stand 9; the air-floating frictionless cylinder 53 is fixed on the stand 9 through the cylinder base 1 55 and the cylinder base 2 56, one end of which extends out of the cylinder rod 52 and is connected to the main shaft 33 through the universal joint 2 51, and the other end is connected to the low-pressure air supply device 6; the pressure sensor 2 54 is installed above the air-floating frictionless cylinder 53 to measure the intake pressure in real time.

[0042] The low-pressure air supply device 6 includes a low-pressure air inlet pipe 61 and a low-pressure stabilizing tank 62 , which provide a stable air source for the air-floating frictionless cylinder 53 .

[0043] The cylinder barrel 23, the push rod 26, the main shaft 33, and the cylinder rod 52 are on the same axis, parallel to the axis of the balance rod 38 and the booster rod 41, and at the same height;

[0044] The frictionless guide ring 29, universal joint 1 27, universal joint 2 51, and balance bar 8 play a role in correcting deviation;

[0045] The displacement sensor 7 is fixed on the stand 9 to measure the displacement change of the connecting plate 34 in real time, thereby obtaining the motion state of the ejector rod 26 and the sealing ring to be measured.

[0046] The method for using the friction characteristics testing device of the sealing ring under high pressure conditions is as follows:

[0047] S1: Use the high-pressure air supply device 1 to inflate the cylinder 23, and the push rod 26 and the sealing ring to be tested form a sealed space in the cylinder 23. The pressure sensor 21 measures the pressure P1 there. Assuming that the direction of movement of the push rod 26 toward the front end cover 22 is positive, the pneumatic load F1=-P1·A1 on the push rod 26 and the sealing ring to be tested can be calculated from the ventilation area A1 of the cylinder 23;

[0048] S2: The low-pressure air supply device 6 inflates the air-floating frictionless cylinder 53, so that the cylinder rod 52, the main shaft 33, and the push rod 26 are close to a balanced state. The pressure sensor 54 measures the pressure P2 there. The balancing force F2 provided by the air-floating frictionless cylinder 53 can be calculated based on the ventilation area A2 of the air-floating frictionless cylinder 53 = P2·A2;

[0049] S3: The power device 4 drives the force rod 41 to apply force to the main shaft 33 through the connecting plate 34, driving the push rod 26 and the tested sealing ring to move back and forth in the cylinder 23, and the tension pressure sensor 8 measures the force F3 in real time;

[0050] S4: Derivatively obtain the movement velocity v and acceleration a of the connecting plate 34 according to the measurement result of the displacement sensor 7;

[0051] Consider the push rod 26, universal joint 1 27, main shaft 33, connecting plate 34, universal joint 2 51, cylinder rod 52 as a whole, with a mass of m. According to Newton's law of motion, the friction force F of the tested sealing ring in this motion state is obtained. f =ma-(F1+F2+F3).

[0052] S5: The present invention adopts the combination of cylinder 23, push rod 26 and sealing groove, which can be used to test sealing rings of different pressure states, different sizes and different materials; the pulling device 3 and the balancing device 5 are used to realize friction testing under high pressure and atmospheric dynamic load conditions, which improves the pressure conditions of existing testing devices; the air bearing is used to reduce system errors; the displacement sensor 7, pressure sensor and tension pressure sensor 8 are used to obtain the friction characteristics of the sealing ring under different motion states such as static and dynamic.

[0053] The embodiments of the present invention described above are only used to help explain the present invention. These embodiments are selected and specifically described in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The embodiments do not describe all the details in detail, nor do they limit the invention to the specific embodiments described. Obviously, many modifications and changes can be made according to the content of this specification, which all belong to the protection scope of the present invention.

Claims

1. A friction characteristic testing device for sealing rings under high pressure conditions, characterized in that: It comprises a high-pressure air supply device (1), a device to be tested (2), a pulling device (3), a power device (4), a balancing device (5), a low-pressure air supply device (6), a displacement sensor (7), a pulling pressure sensor (8), and a stand (9); One end of the device under test (2) is connected to the high-pressure gas supply device (1), and the other end is connected to the pulling device (3); One end of the balancing device (5) is connected to the low-pressure air supply device (6), and the other end is connected to the pulling device (3); The power device (4) is mechanically fixed on the stand (9) and vertically connected to the pulling device (3) via a pulling pressure sensor (8); The displacement sensor (7) is fixed on the stand (9) to measure the displacement change of the pulling device (3) in real time; The tension and pressure sensor (8) measures the applied driving force in real time.

2. A friction characteristic testing device for a sealing ring under high pressure conditions as claimed in claim 1, characterized in that: The high-pressure gas supply device (1) comprises a high-pressure stabilizing tank (11) and a high-pressure gas inlet pipe (12).

3. A friction characteristic testing device for a sealing ring under high pressure conditions as claimed in claim 1, characterized in that: The device under test (2) comprises a pressure sensor 1 (21), a front end cover (22), a cylinder barrel (23), an end cover connecting rod (24), a rear end cover (25), a push rod (26), a universal joint 1 (27), a device under test base (28), and a frictionless guide ring (29); The front end cover (22) and the rear end cover (25) are fixed on the base (28) of the device under test by means of screws; The cylinder barrel (23) is installed between the front end cover (22) and the rear end cover (25), and is fastened by four end cover connecting rods (24); The other side of the front end cover (22) is connected to the high-pressure air intake pipe (12), and a pressure sensor (21) is installed on the top to measure the air intake pressure in real time; A guide ring (29) is installed on the other side of the rear end cover (25) and has a through hole on the top; A sealing groove is formed at one end of the push rod (26) for mounting a tested sealing ring; The other end of the push rod (26) is installed with a universal joint 1 (27) and is connected to the pulling device (3) via the universal joint 1 (27). The push rod (26) extends from the rear end cover (25) into the cylinder barrel (23) through a frictionless guide ring (29).

4. A friction characteristic testing device for a sealing ring under high pressure conditions as claimed in claim 1, characterized in that: The pulling device (3) comprises a pulling device base (31), an air bearing 1 (32), a main shaft (33), a connecting plate (34), an air bearing 2 (35), a hydraulic buffer device 1 (36), a balancing rod (37), an air bearing 3 (38), and a hydraulic buffer device 2 (39); The air bearing 1 (32) and the air bearing 2 (35) are fixed on the pulling device base (31) by screws to support the main shaft (33) to float; The balance rod (37) is fixed on the pulling device base (31) and is installed parallel to the main shaft (33); The connecting plate (34) is perpendicular to the main shaft (33) and the balance rod (37), one end of which is fixedly connected to the main shaft (33) by bolts, and the other end of which is installed with an air bearing three (38); The air bearing 3 (38) passes through the balance rod (37) and can move along the balance rod (37) without friction; Limit baffles are installed at both ends of the main shaft (33) and are respectively connected to universal joint 1 (27) and universal joint 2 (51); The hydraulic buffer device 1 (36) and the hydraulic buffer device 2 (39) play the role of anti-collision and buffering.

5. A friction characteristic testing device for a sealing ring under high pressure conditions as claimed in claim 1, characterized in that: The power device (4) is equipped with a force adding rod (41); The boosting rod (41) is parallel to the balancing rod (37) and vertically connected to the connecting plate (34) through a tension pressure sensor (8). When the boosting rod (41) moves forward and backward, the power device (4) can drive the connecting plate (34) and the main shaft (33) to move together.

6. A friction characteristic testing device for a sealing ring under high pressure conditions as claimed in claim 1, characterized in that: The balancing device (5) comprises a universal joint 2 (51), a cylinder rod (52), an air-floating frictionless cylinder (53), a pressure sensor 2 (54), a cylinder base 1 (55), and a cylinder base 2 (56); The cylinder base 1 (55) and the cylinder base 2 (56) are installed on the stand (9); The air-floating frictionless cylinder (53) is fixed on the stand (9) through a cylinder base 1 (55) and a cylinder base 2 (56), one end of which extends out of the cylinder rod (52) and is connected to the main shaft (33) through a universal joint 2 (51), and the other end is connected to a low-pressure air supply device (6); The second pressure sensor (54) is installed above the air-floating frictionless cylinder (53) to measure the intake pressure in real time.

7. A friction characteristic testing device for a sealing ring under high pressure conditions as claimed in any one of claims 1 to 6, characterized in that: The cylinder barrel (23), the push rod (26), the main shaft (33), and the cylinder rod (52) are located on the same axis, parallel to the axes of the balance rod (38) and the force rod (41), and are at the same height.

8. A friction characteristic testing device for a sealing ring under high pressure conditions as claimed in claim 1, characterized in that: The low-pressure air supply device (6) comprises a low-pressure air inlet pipe (61) and a low-pressure stabilizing tank (62), and provides a stable air source for the air-floating frictionless cylinder (53).

9. A method for using a friction characteristic testing device for a sealing ring under high pressure conditions, characterized in that: S1: using the high-pressure air supply device (1) to inflate the cylinder (23), the push rod (26) and the sealing ring to be tested form a sealed space in the cylinder (23), and the pressure sensor 1 (21) measures the pressure P1 at the space. Assuming that the direction of movement of the push rod (26) toward the front end cover (22) is positive, the pneumatic load F1 = -P1·A1 on the push rod (26) and the sealing ring to be tested is calculated based on the ventilation area A1 of the cylinder (23); S2: The low-pressure air supply device (6) inflates the air-floating frictionless cylinder (53) to bring the cylinder rod (52), the main shaft (33) and the push rod (26) into a state close to equilibrium. The second pressure sensor (54) measures the pressure P2 there. Based on the ventilation area A2 of the air-floating frictionless cylinder (53), the balancing force F2=P2·A2 provided by the air-floating frictionless cylinder (53) is calculated; S3: The power device (4) drives the force rod (41) to apply a force to the main shaft (33) through the connecting plate (34), driving the push rod (26) and the tested sealing ring to move forward and backward in the cylinder (23), and the tension pressure sensor (8) measures the force F3 in real time; S4: Derivatively obtain the movement velocity v and acceleration a of the connecting plate (34) based on the measurement result of the displacement sensor (7); S5: Consider the push rod (26), universal joint 1 (27), main shaft (33), connecting plate (34), universal joint 2 (51), cylinder rod (52) etc. as a whole, with a mass of m. According to Newton's law of motion, the friction force F of the tested sealing ring in this motion state is obtained: f =ma-(F1+F2+F3).

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