Portable safety valve opening pressure verification device and use method thereof

Abstract

The invention discloses a portable safety valve opening pressure verification device and a using method thereof, and belongs to the field of safety valve verification. The portable safety valve opening pressure verification device comprises a supporting and positioning mechanism at the bottom end of a valve seat, a supporting frame, a cap screwing mechanism and a valve rod torque loading mechanism; the valve rod torque loading mechanism comprises a lifting driving air cylinder fixed to the side portion of the supporting frame, a telescopic driving air cylinder connected with the top output end of the lifting driving air cylinder and an electric wrench connected with the horizontal output end of the telescopic driving air cylinder, the torque output end of the electric wrench is connected with a sleeve, and a nut is arranged in the sleeve. The sleeve is further connected with a first clamping unit through a lifting pull rod, and the nut and the first clamping unit are both matched with the outer circumferential side of the valve rod. According to the portable safety valve opening pressure verification device and the use method thereof, the electric wrench is used for driving the valve rod to be lifted, the opening pressure is calculated through the peak value recorded by the electric wrench, the precision can reach 0.001% FS, and the measurement precision is greatly improved.

Description

Technical Field

[0001] The present invention relates to the technical field of safety valve calibration, and in particular to a convenient safety valve opening pressure calibration device and a use method thereof. Background Art

[0002] Safety valve is an important automatic valve, mainly used to protect various pressure-bearing equipment such as boilers, pressure vessels and pipelines, to prevent accidents caused by excessive pressure. Its working principle is as follows: Under normal working conditions, the valve core of the safety valve remains closed under the action of the loading mechanism (such as spring force) to prevent the medium from flowing out. When the pressure in the equipment or pipeline exceeds the preset safety value for some reason, the force of the medium pressure on the valve core will exceed the force applied by the loading mechanism, causing the valve core to open, thereby discharging the excess medium to the outside of the system to prevent the pressure from continuing to rise. Once the pressure drops to within the safety range, the valve core will close again under the action of the loading mechanism to stop the discharge.

[0003] As an indispensable safety device in the pressure system, the safety valve can be operated automatically without manual intervention. However, in order to ensure the reliability of the safety valve, all safety valves must undergo strict calibration and pressure testing before installation, and comply with the standards of relevant countries and regions. In addition, regular inspection and maintenance are required during use to maintain its normal function.

[0004] Existing safety valve periodic calibration equipment, such as the safety valve online detector disclosed in CN200610146259.2 and the chemical container safety valve online detector disclosed in CN200620162187.6, all use sensors to detect the opening pressure of the safety valve, which has the following problems:

[0005] 1. The accuracy of the sensor is 0.5% FS, resulting in low measurement accuracy;

[0006] 2. The operator needs to hold the lifting device in hand, which may cause manual operation errors and increase the labor intensity.

[0007] 3. The equipment is heavy and inconvenient to move. Summary of the invention

[0008] In order to solve the above problems, the present invention provides a convenient safety valve opening pressure calibration device and a method for using the same. By using an electric wrench to drive the valve stem to lift, the opening pressure is calculated using the peak value recorded by the electric wrench, and the accuracy can reach 0.001% FS, which greatly improves the measurement accuracy.

[0009] To achieve the above-mentioned purpose, the present invention provides a convenient safety valve opening pressure calibration device, comprising a supporting and positioning mechanism for clamping the bottom end of the valve seat of the safety valve to be calibrated, a supporting frame connected to the supporting and positioning mechanism, a cap screwing mechanism arranged at the top end of the supporting frame aligned with the valve cap of the safety valve, and a valve stem torque loading mechanism arranged at the side of the supporting frame aligned with the valve stem of the safety valve, the valve stem torque loading mechanism comprising a lifting drive cylinder fixed to the side of the supporting frame, a telescopic drive cylinder connected to the top output end of the lifting drive cylinder, and an electric wrench connected to the horizontal output end of the telescopic drive cylinder, the torque output end of the electric wrench is connected to a sleeve, a nut is arranged in the sleeve, and the sleeve is also connected to a first clamping unit via a lifting pull rod, and the nut and the first clamping unit are both adapted to the outer circumferential side of the valve stem.

[0010] Preferably, the supporting and positioning mechanism comprises a second clamping unit adapted to the outer circumferential side of the valve seat;

[0011] The second clamping unit and the first clamping unit both include a mounting plate, a driving ring horizontally rotatably arranged on the mounting plate, an annular rack is arranged on the outer circumference side of the middle part of the driving ring, the annular rack is meshed with a first driving gear horizontally rotatably arranged on the mounting plate, and the first driving gear is connected to the output end of the clamping driving motor fixed on the mounting plate;

[0012] A plurality of guide posts are evenly fixed on the top of the driving ring in a circumferential array, and a plurality of driven sleeves are vertically rotated on the driving ring. A plurality of arc-shaped guide grooves arranged in an annular pattern are provided on the inner circumference of the driven sleeves, and the arc-shaped guide grooves are slidably connected with the guide posts;

[0013] A gear ring is provided on the outer circumference of the driven sleeve, the gear ring meshes with a linear rack radially slidably arranged on the mounting plate, and an arc-shaped clamping plate is fixed on the linear rack facing the direction of the center of the driving ring;

[0014] A plurality of driven sleeves are evenly arranged on the driving ring in a circumferential array, a plurality of arc-shaped clamping plates surround the clamping ring, the inner circumference side of the clamping ring of the first clamping unit is matched with the outer circumference side of the valve stem, and the inner circumference side of the clamping ring of the second clamping unit is matched with the outer circumference side of the valve seat;

[0015] The mounting plate of the second clamping unit is provided with a through hole corresponding to the position of the safety valve to be checked.

[0016] Preferably, the middle position of the driven sleeve is meshed with the linear rack, and both ends of the driven sleeve are vertically rotatably connected to the mounting plate via bearings.

[0017] Preferably, the mounting plate of the first clamping unit is horizontally rotatably connected to the bottom end of the lifting rod, and the lifting rod is an axial telescopic rod;

[0018] The center position of the bottom end of the mounting plate of the second clamping unit is clamped on the pipeline through an elastic arc-shaped clamping plate, and a telescopic transfer wheel assembly is fixed at the bottom edge position of the mounting plate of the second clamping unit. The telescopic transfer wheel assembly includes a top sleeve and a bottom telescopic rod vertically slidably arranged in the top sleeve. The bottom end of the bottom telescopic rod is vertically rotatably connected to the transfer wheel, and the transfer wheel is a self-locking universal wheel.

[0019] A strip-shaped adjusting hole is provided on the top sleeve, a positioning hole is provided at the position where the bottom telescopic rod extends into the top sleeve, and a positioning pin passes through the strip-shaped adjusting hole and is connected with the positioning hole.

[0020] Preferably, a resin layer is bonded to a side of the arc-shaped clamping plate that faces away from the linear driving rack.

[0021] Preferably, the cap screwing mechanism comprises a rotating lifting assembly arranged on the support frame and a third clamping unit connected to the output end of the rotating lifting assembly, and the third clamping unit is adapted to the outer circumferential side of the valve cap.

[0022] Preferably, the rotary lifting assembly includes a rotary lifting drive motor fixed on the support frame, a second driving gear connected to the output end of the rotary lifting drive motor, and a driven gear meshing with the second driving gear, the driven gear is threadedly connected to the top end of the first screw rod through a thread, and the bottom end of the first screw rod passes through the support frame and is connected to the third clamping unit;

[0023] The third clamping unit includes a fixed plate fixedly connected to the bottom end of the screw rod, and two semicircular clamping plates radially slidably arranged on the fixed plate at the top end. The opposite sides of the two semicircular clamping plates are bent outward to form push-pull plates. A clamping drive motor is fixed on one of the push-pull plates. The clamping drive motor is connected to one end of the second screw rod, and the other end of the second screw rod is threadedly connected to the other push-pull plate.

[0024] Preferably, the inner circumference sides of the arc-shaped clamping plate and the semicircular clamping plate are both inlaid with pressure sensors, the pressure sensor on the arc-shaped clamping plate is electrically connected to the clamping drive motor via the controller, and the pressure sensor on the semicircular clamping plate is electrically connected to the rotation and lifting drive motor and the clamping drive motor via the controller;

[0025] An encoder is arranged on the output shaft of the rotary lifting drive motor, and the encoder is electrically connected to the rotary lifting drive motor and the clamping drive motor respectively through a controller.

[0026] A method for using a portable safety valve opening pressure calibration device comprises the following steps:

[0027] S1. Hold the inspection device and lift it above the safety valve to be inspected, and align the through hole of the mounting plate of the second clamping unit with the safety valve to be inspected;

[0028] S2, moving the calibration device downward until the elastic arc-shaped clamping plate at the bottom end of the mounting plate of the second clamping unit is clamped on the pipeline;

[0029] S3, turn on the clamping drive motor of the second clamping unit, the clamping drive motor drives the first drive gear of the second clamping unit to rotate, and then drives the annular rack of the second clamping unit to rotate horizontally, and then uses the guide column to cooperate with the arc guide groove to drive multiple driven sleeves on the annular rack to rotate synchronously, and then drives the linear rack to move in the direction close to the center of the annular rack, until the arc clamping plate of the second clamping unit clamps the valve seat, and the value collected by the pressure sensor on the arc clamping plate of the second clamping unit reaches the set value, and the controller sends a stop signal to the clamping drive motor of the second clamping unit, and the clamping drive motor of the second clamping unit stops running;

[0030] S4. Remove the valve cap:

[0031] Turn on the rotary lifting drive motor, and the rotary lifting drive motor drives the first screw rod to move downward through the second driving gear and the driven gear until the encoder detects the descent to the set distance. At this time, the two semicircular clamping plate covers are arranged on the outside of the valve bonnet, and a stop signal is sent to the rotary lifting drive motor through the controller, and a start signal is sent to the clamping drive motor. The clamping drive motor drives the second screw rod to rotate, and the distance between the two semicircular clamping plates is shortened under the cooperation of the threads until the two semicircular clamping plates clamp the valve bonnet, and the pressure sensor on the semicircular clamping plates detects that the pressure value reaches the set value, and a stop signal is sent to the clamping drive motor through the controller, and a reverse start signal is sent to the rotary lifting drive motor at the same time. The rotary lifting drive motor runs in the reverse direction, driving the first screw rod to rotate upward, and the clamped valve bonnet is removed;

[0032] S5. Verification:

[0033] The lifting drive cylinder drives the first clamping unit upward, and then the telescopic drive cylinder drives the second clamping unit to move toward the valve stem until the first clamping unit is located above the valve stem, the telescopic drive cylinder is closed, and the lifting drive cylinder drives the first clamping unit downward until the clamping ring is set on the outside of the valve stem;

[0034] The clamping drive motor of the first clamping unit is turned on, and the clamping drive motor drives the first drive gear of the first clamping unit to rotate, thereby driving the annular rack of the first clamping unit to rotate horizontally, and then the guide column is used to cooperate with the arc guide groove to drive multiple driven sleeves on the annular rack to rotate synchronously, thereby driving the linear rack to move in the direction close to the center of the annular rack, until the arc clamping plate of the first clamping unit clamps the valve stem, and the value collected by the pressure sensor on the arc clamping plate of the first clamping unit reaches the set value, and a stop signal is sent to the clamping drive motor of the first clamping unit through the controller, and the clamping drive motor of the first clamping unit stops running. At this time, the arc clamping plate is used to limit the valve stem from rotating in the circumferential direction;

[0035] Open the electric wrench and the lifting drive cylinder of the first clamping unit, the electric wrench screws the nut onto the valve stem, then the clamping drive motor of the first clamping unit rotates in the reverse direction, driving the arc-shaped clamping plate to loosen the valve stem, releasing the circumferential limit of the valve stem, closing the clamping drive motor of the first clamping unit, opening the electric wrench, and driving the nut to rotate in the reverse direction. Under the action of the internal thread of the nut and the external thread of the valve stem, the valve stem is lifted until the first collection peak value is collected by the electric wrench, and the axial tension is calculated using the first collection peak value, and this axial tension is used as the opening pressure of the safety valve;

[0036] S6, reverse the operation of step S5, remove the first clamping unit, reverse the operation of step S4, install the valve cap, and finally reverse the operation of step S3, remove the second clamping unit, and finally remove the verification device to complete the verification.

[0037] Preferably, in step S5, the calculation formula for calculating the axial tension using the first collected peak value is:

[0038] T=kdF

[0039] Where, T is the tightening torque, in Nm; F is the axial tension, in N; d is the nominal diameter of the screw, in m; k is the torque coefficient;

[0040] Push out the axial tension F=T / kd.

[0041] The present invention has the following beneficial effects:

[0042] 1. By using an electric wrench to drive the valve stem to lift, the opening pressure is calculated using the peak value recorded by the electric wrench, with an accuracy of 0.001% FS, which greatly improves the measurement accuracy;

[0043] 2. During the calibration, the calibration device is directly connected to the pipeline and the safety valve. After the valve cap is unscrewed with the help of the cap tightening mechanism, the electric wrench can be used for testing. No human intervention is required during the test, which reduces human errors. At the same time, there is no need for the operator to hold the tester all the time, which reduces the labor intensity of the operator and makes it more convenient to use.

[0044] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 This is a diagram showing the use status of a portable safety valve opening pressure calibration device of the present invention;

[0046] Figure 2 It is a schematic structural diagram of a second clamping unit of a portable safety valve opening pressure calibration device of the present invention;

[0047] Figure 3 It is a transmission schematic diagram of a second clamping unit of a convenient safety valve opening pressure testing device of the present invention;

[0048] Figure 4 A guide groove arrangement diagram of a second clamping unit of a convenient safety valve opening pressure testing device of the present invention;

[0049] Figure 5 It is an assembly diagram of a mounting plate of a second clamping unit of a portable safety valve opening pressure testing device of the present invention;

[0050] Figure 6 The present invention is a schematic diagram of the semicircular clamping plate structure of a convenient safety valve opening pressure calibration device. Figure 7 This is a schematic diagram of the cooperation between an electric wrench and a valve stem of a convenient safety valve opening pressure calibration device of the present invention.

[0051] Among them: 1. Rotating and lifting drive motor; 2. Second drive gear; 3. First screw; 4. Driven gear; 5. Handle; 6. Support frame; 7. Semicircular clamping plate; 8. Valve bonnet; 9. Valve stem; 10. Drive ring; 11. Driven sleeve; 12. Linear rack; 13. Mounting plate; 14. Pipeline; 15. Valve seat; 16. Lifting rod; 17. Lifting drive cylinder; 18. Telescopic drive cylinder; 19. Electric wrench; 20. Arc clamping plate; 21. First drive gear; 22. Guide column; 23. Perforation; 24. Arc guide groove; 25. Elastic arc clamping plate; 26. Top sleeve; 27. Bottom telescopic rod; 28. Transfer wheel; 29. ​​Clamping drive motor; 30. Second screw; 31. Nut; 32. Sleeve. DETAILED DESCRIPTION

[0052] In order to make the purpose, technical scheme and advantages disclosed in the embodiments of the present invention clearer, the embodiments of the present invention are further described in detail in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the embodiments of the present invention and are not intended to limit the embodiments of the present invention. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions.

[0053] It should be noted that the terms "include", "have" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or server comprising a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to these processes, methods, products or devices.

[0054] Like reference numerals and letters denote similar items in the following drawings, and thus, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0055] In the description of the present invention, it should be noted that the terms "upper", "lower", "inside", "outside", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, or are directions or positional relationships in which the product of the invention is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present invention.

[0056] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "setting", "installation" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0057] A convenient safety valve opening pressure calibration device comprises a supporting and positioning mechanism for clamping the bottom end of a valve seat 15 of a safety valve to be calibrated, a supporting frame 6 connected to the supporting and positioning mechanism, a cap screwing mechanism arranged at the top end of the supporting frame 6 for aligning a valve cap 8 of the safety valve, and a valve stem torque loading mechanism arranged at the side of the supporting frame 6 for aligning a valve stem 9 of the safety valve, the valve stem torque loading mechanism comprising a lifting drive cylinder 17 fixed to the side of the supporting frame 6, a telescopic drive cylinder 18 connected to the top output end of the lifting drive cylinder 17, and an electric wrench 19 connected to the horizontal output end of the telescopic drive cylinder 18, the torque output end of the electric wrench 19 is connected to a sleeve 32, a nut 31 is arranged in the sleeve 32, the sleeve 32 is also connected to a first clamping unit via a lifting rod 16, and the nut 31 and the first clamping unit are both adapted to the outer circumferential side of the valve stem 9.

[0058] Among them, the supporting and positioning mechanism includes a second clamping unit adapted to the outer circumferential side of the valve seat 15; the second clamping unit and the first clamping unit both include a mounting plate 13, a driving ring 10 horizontally rotatably arranged on the mounting plate 13, an annular rack is arranged on the middle outer circumferential side of the driving ring 10, the annular rack is meshed with a first driving gear 21 horizontally rotatably arranged on the mounting plate 13, and the first driving gear 21 is connected to the output end of the clamping driving motor fixed on the mounting plate 13; a plurality of guide columns 22 are evenly fixed on the top of the driving ring 10 in a circular array, and a plurality of driven sleeves 11 are also vertically rotatable on the driving ring 10, and a plurality of arcs arranged in a circular shape are opened on the inner circumferential side of the driven sleeve 11 shaped guide groove 24, arc-shaped guide groove 24 is slidably connected with guide column 22; a gear ring is provided on the outer circumferential side of driven sleeve 11, the gear ring is meshed with a linear rack 12 radially slidably arranged on mounting plate 13, and an arc-shaped clamping plate 20 is fixed on the linear rack 12 facing the direction of the center of the driving ring 10; a plurality of driven sleeves 11 are evenly arranged on the driving ring 10 in a circular array, and a plurality of arc-shaped clamping plates 20 form a clamping ring, the inner circumferential side of the clamping ring of the first clamping unit is matched with the outer circumferential side of the valve stem 9, and the inner circumferential side of the clamping ring of the second clamping unit is matched with the outer circumferential side of the valve seat 15; a through hole 23 is provided on the mounting plate 13 of the second clamping unit corresponding to the position of the safety valve to be checked.

[0059] The middle position of the driven sleeve 11 is meshed with the linear rack 12, and both ends of the driven sleeve 11 are vertically rotatably connected to the mounting plate 13 via bearings.

[0060] The mounting plate 13 of the first clamping unit is horizontally rotatably connected to the bottom end of the lifting rod 16. The lifting rod is an axial telescopic rod, that is, the lifting rod is axially telescopic and its circumferential rotation is limited. This structure can be a telescopic tube structure, that is, the telescopic tube includes an outer tube and an inner tube, and the outer wall of the inner tube protrudes outward to form an axial guide protrusion, and the outer tube is provided with an axial guide groove at a position corresponding to the axial guide protrusion, so as to realize axial movement and limit circumferential rotation; the bottom center position of the mounting plate 13 of the second clamping unit is clamped to the pipeline through an elastic arc clamping plate 25 14, and a telescopic transport wheel 28 assembly is fixed at the bottom edge of the mounting plate 13 of the second clamping unit. The telescopic transport wheel 28 assembly includes a top sleeve 26 and a bottom telescopic rod 27 vertically slidably arranged in the top sleeve 26. The bottom end of the bottom telescopic rod 27 is vertically rotatably connected to the transport wheel 28. The transport wheel 28 is a self-locking universal wheel. A strip-shaped adjustment hole is provided on the top sleeve 26, and a positioning hole is provided at the position where the bottom telescopic rod 27 extends into the top sleeve 26. The positioning pin passes through the strip-shaped adjustment hole and is connected to the positioning hole. At the same time, a handle 5 is also fixed on the top of the support frame 6 to facilitate pushing and pulling the calibration device, as well as lifting the calibration device.

[0061] A resin layer is bonded to the side of the arc-shaped clamping plate 20 that is away from the linear drive rack, so as to increase the friction force while avoiding wear on the safety valve.

[0062] The cap screwing mechanism comprises a rotating lifting assembly arranged on the support frame 6 and a third clamping unit connected to the output end of the rotating lifting assembly, and the third clamping unit is adapted to the outer circumferential side of the valve cap 8 .

[0063] The rotating and lifting assembly includes a rotating and lifting drive motor 1 fixed on a support frame 6, a second driving gear 2 connected to the output end of the rotating and lifting drive motor 1, and a driven gear 4 meshing with the second driving gear 2, wherein the driven gear 4 is threadedly connected to the top end of the first screw rod 3 through a thread, and the bottom end of the first screw rod 3 passes through the support frame 6 and is connected to the third clamping unit; the third clamping unit includes a fixed plate fixedly connected to the bottom end of the screw rod, and two semicircular clamping plates 7 radially slidably arranged on the fixed plate at the top end, and the opposite sides of the two semicircular clamping plates 7 are bent outward to form push-pull plates, and a clamping drive motor 29 is fixed on one of the push-pull plates, and the clamping drive motor 29 is connected to one end of the second screw rod 30, and the other end of the second screw rod 30 is threadedly connected to the other push-pull plate.

[0064] Pressure sensors are embedded on the inner circumference sides of the arc-shaped clamping plate 20 and the semicircular clamping plate 7. The pressure sensor on the arc-shaped clamping plate 20 is electrically connected to the clamping drive motor via a controller, and the pressure sensor on the semicircular clamping plate 7 is electrically connected to the rotating lifting drive motor 1 and the clamping drive motor 29 respectively via a controller; an encoder is provided on the output shaft of the rotating lifting drive motor 1, and the encoder is electrically connected to the rotating lifting drive motor 1 and the clamping drive motor 29 respectively via a controller.

[0065] It should be noted that the above-mentioned electronic components are mature products on the market. This embodiment only needs to purchase them and connect them according to the instructions. No improvement is made to them, so their circuit connection structure and principle will not be described in detail here.

[0066] A method for using a safety valve opening pressure calibration device on a pipeline 14 comprises the following steps:

[0067] S1. Hold the inspection device and lift it above the safety valve to be inspected, and align the through hole 23 of the mounting plate 13 of the second clamping unit with the safety valve to be inspected;

[0068] S2, move the calibration device downward until the elastic arc-shaped clamping plate 25 at the bottom end of the mounting plate 13 of the second clamping unit is clamped on the pipe 14;

[0069] S3, turn on the clamping drive motor of the second clamping unit, the clamping drive motor drives the first drive gear 21 of the second clamping unit to rotate, and then drives the annular rack of the second clamping unit to rotate horizontally, and then uses the guide column 22 to cooperate with the arc guide groove 24 to drive the multiple driven sleeves 11 on the annular rack to rotate synchronously, and then drives the linear rack 12 to move toward the center of the annular rack, until the arc clamping plate 20 of the second clamping unit clamps the valve seat 15, and the value collected by the pressure sensor on the arc clamping plate 20 of the second clamping unit reaches the set value, and the controller sends a stop signal to the clamping drive motor of the second clamping unit, and the clamping drive motor of the second clamping unit stops running;

[0070] S4. Remove the valve cap 8:

[0071] Turn on the rotary lifting drive motor 1, and the rotary lifting drive motor 1 drives the first screw 3 to move downward through the second driving gear 2 and the driven gear 4 until the encoder collects the drop to the set distance. At this time, the two semicircular clamping plates 7 are covered on the outside of the valve bonnet 8. The controller sends a stop signal to the rotary lifting drive motor 1, and sends a start signal to the clamping drive motor 29. The clamping drive motor 29 drives the second screw 30 to rotate, and the distance between the two semicircular clamping plates 7 is shortened under the cooperation of the threads until the two semicircular clamping plates 7 clamp the valve bonnet 8, and the pressure sensor on the semicircular clamping plates 7 collects that the pressure value reaches the set value, and sends a stop signal to the clamping drive motor 29 through the controller, and at the same time sends a reverse start signal to the rotary lifting drive motor 1. The rotary lifting drive motor 1 runs in the reverse direction, driving the first screw 3 to rotate upward, and the clamped valve bonnet 8 is removed;

[0072] S5. Verification:

[0073] The lifting drive cylinder 17 drives the first clamping unit upward, and then the telescopic drive cylinder 18 drives the second clamping unit to move toward the valve stem 9 until the first clamping unit is located above the valve stem 9, and then the telescopic drive cylinder 18 is closed, and the lifting drive cylinder 17 drives the first clamping unit downward until the clamping ring is set outside the valve stem 9;

[0074] The clamping drive motor of the first clamping unit is turned on, and the clamping drive motor drives the first drive gear 21 of the first clamping unit to rotate, thereby driving the annular rack of the first clamping unit to rotate horizontally, and then the guide column 22 cooperates with the arc guide groove 24 to drive the multiple driven sleeves 11 on the annular rack to rotate synchronously, thereby driving the linear rack 12 to move toward the center of the annular rack, until the arc clamping plate 20 of the first clamping unit clamps the valve stem, and the value collected by the pressure sensor on the arc clamping plate 20 of the first clamping unit reaches the set value, and the controller sends a stop signal to the clamping drive motor of the first clamping unit, and the clamping drive motor of the first clamping unit stops running. At this time, the arc clamping plate 20 is used to limit the valve stem 9 from rotating in the circumferential direction;

[0075] The electric wrench 19 and the lifting drive cylinder 17 of the first clamping unit are turned on, and the electric wrench 19 screws the nut onto the valve stem. Then, the clamping drive motor 29 of the first clamping unit rotates in the reverse direction, driving the arc-shaped clamping plate 20 to loosen the valve stem, releasing the circumferential limit of the valve stem 9, and the clamping drive motor 29 of the first clamping unit is turned off. The electric wrench 19 is turned on, and the electric wrench 19 drives the nut to rotate in the reverse direction. Under the action of the internal thread of the nut 31 and the external thread of the valve stem 9, the valve stem 9 is lifted until the first collection peak value is collected by the electric wrench 19. The axial tension is calculated using the first collection peak value, and this axial tension is used as the opening pressure of the safety valve;

[0076] In step S5, the calculation formula for calculating the axial tension using the first collected peak value is:

[0077] T=kdF

[0078] Where, T is the tightening torque, in Nm; F is the axial tension, in N; d is the nominal diameter of the screw, in m; k is the torque coefficient;

[0079] Push out the axial tension F=T / kd.

[0080] S6, reverse the operation of step S5, remove the first clamping unit, reverse the operation of step S4, install the valve cap 8, and finally reverse the operation of step S3, remove the second clamping unit, and finally remove the verification device to complete the verification.

[0081] Therefore, the present invention adopts the above-mentioned convenient safety valve opening pressure calibration device and its use method, uses an electric wrench to drive the valve stem to lift, and uses the peak value recorded by the electric wrench to calculate the opening pressure, with an accuracy of up to 0.001% FS, which greatly improves the measurement accuracy.

[0082] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. A convenient safety valve opening pressure calibration device, characterized in that: It includes a supporting and positioning mechanism for clamping the bottom end of the valve seat of the safety valve to be checked, a supporting frame connected to the supporting and positioning mechanism, a cap tightening mechanism arranged at the top end of the supporting frame to align with the valve cap of the safety valve, and a valve stem torque loading mechanism arranged at the side of the supporting frame to align with the valve stem of the safety valve. The valve stem torque loading mechanism includes a lifting drive cylinder fixed to the side of the supporting frame, a telescopic drive cylinder connected to the top output end of the lifting drive cylinder, and an electric wrench connected to the horizontal output end of the telescopic drive cylinder. The torque output end of the electric wrench is connected to a sleeve, a nut is arranged in the sleeve, and the sleeve is also connected to a first clamping unit via a lifting pull rod. The nut and the first clamping unit are both adapted to the outer circumferential side of the valve stem.

2. A portable safety valve opening pressure calibration device according to claim 1, characterized in that: The supporting and positioning mechanism includes a second clamping unit adapted to the outer circumferential side of the valve seat; The second clamping unit and the first clamping unit both include a mounting plate, a driving ring horizontally rotatably arranged on the mounting plate, an annular rack is arranged on the outer circumference side of the middle part of the driving ring, the annular rack is meshed with a first driving gear horizontally rotatably arranged on the mounting plate, and the first driving gear is connected to the output end of the clamping driving motor fixed on the mounting plate; A plurality of guide posts are evenly fixed on the top of the driving ring in a circular array, and a plurality of driven sleeves are vertically rotated on the driving ring. A plurality of arc-shaped guide grooves arranged in an annular pattern are provided on the inner circumference of the driven sleeves, and the arc-shaped guide grooves are slidably connected with the guide posts; A gear ring is provided on the outer circumference of the driven sleeve, the gear ring meshes with a linear rack radially slidably arranged on the mounting plate, and an arc-shaped clamping plate is fixed on the linear rack facing the direction of the center of the driving ring; A plurality of driven sleeves are evenly arranged on the driving ring in a circumferential array, a plurality of arc-shaped clamping plates surround the clamping ring, the inner circumference side of the clamping ring of the first clamping unit is matched with the outer circumference side of the valve stem, and the inner circumference side of the clamping ring of the second clamping unit is matched with the outer circumference side of the valve seat; The mounting plate of the second clamping unit is provided with a through hole corresponding to the position of the safety valve to be checked.

3. A portable safety valve opening pressure calibration device according to claim 2, characterized in that: The middle position of the driven sleeve is meshed with the linear rack, and the two ends of the driven sleeve are vertically rotatably connected with the mounting plate via bearings.

4. A portable safety valve opening pressure calibration device according to claim 3, characterized in that: The mounting plate of the first clamping unit is horizontally rotatably connected to the bottom end of the lifting rod, and the lifting rod is an axial telescopic rod; The center position of the bottom end of the mounting plate of the second clamping unit is clamped on the pipeline through an elastic arc-shaped clamping plate, and a telescopic transfer wheel assembly is fixed at the bottom edge position of the mounting plate of the second clamping unit. The telescopic transfer wheel assembly includes a top sleeve and a bottom telescopic rod vertically slidably arranged in the top sleeve. The bottom end of the bottom telescopic rod is vertically rotatably connected to the transfer wheel, and the transfer wheel is a self-locking universal wheel. A strip-shaped adjusting hole is provided on the top sleeve, a positioning hole is provided at the position where the bottom telescopic rod extends into the top sleeve, and a positioning pin passes through the strip-shaped adjusting hole and is connected with the positioning hole.

5. A portable safety valve opening pressure calibration device according to claim 2, characterized in that: A resin layer is bonded to a side of the arc-shaped clamping plate that is away from the linear driving rack.

6. A portable safety valve opening pressure calibration device according to claim 4, characterized in that: The cap screwing mechanism comprises a rotating lifting assembly arranged on a supporting frame and a third clamping unit connected to an output end of the rotating lifting assembly, wherein the third clamping unit is matched with an outer circumferential side of the valve cap.

7. A portable safety valve opening pressure calibration device according to claim 6, characterized in that: The rotary lifting assembly includes a rotary lifting drive motor fixed on the support frame, a second driving gear connected to the output end of the rotary lifting drive motor, and a driven gear meshing with the second driving gear, wherein the driven gear is threadedly connected to the top end of the first screw rod through a thread, and the bottom end of the first screw rod passes through the support frame and is connected to the third clamping unit; The third clamping unit includes a fixed plate fixedly connected to the bottom end of the screw rod, and two semicircular clamping plates radially slidably arranged on the fixed plate at the top end. The opposite sides of the two semicircular clamping plates are bent outward to form push-pull plates. A clamping drive motor is fixed on one of the push-pull plates. The clamping drive motor is connected to one end of the second screw rod, and the other end of the second screw rod is threadedly connected to the other push-pull plate.

8. A portable safety valve opening pressure calibration device according to claim 7, characterized in that: The inner circumference sides of the arc clamping plate and the semicircular clamping plate are both inlaid with pressure sensors. The pressure sensor on the arc clamping plate is electrically connected to the clamping drive motor via the controller, and the pressure sensor on the semicircular clamping plate is electrically connected to the rotation lifting drive motor and the clamping drive motor via the controller; An encoder is arranged on the output shaft of the rotary lifting drive motor, and the encoder is electrically connected to the rotary lifting drive motor and the clamping drive motor respectively through a controller.

9. The method for using the portable safety valve opening pressure calibration device according to claim 8, characterized in that: The following steps are involved: S1. Hold the inspection device and lift it above the safety valve to be inspected, and align the through hole of the mounting plate of the second clamping unit with the safety valve to be inspected; S2, moving the calibration device downward until the elastic arc-shaped clamping plate at the bottom end of the mounting plate of the second clamping unit is clamped on the pipeline; S3, turn on the clamping drive motor of the second clamping unit, the clamping drive motor drives the first drive gear of the second clamping unit to rotate, and then drives the annular rack of the second clamping unit to rotate horizontally, and then uses the guide column to cooperate with the arc guide groove to drive multiple driven sleeves on the annular rack to rotate synchronously, and then drives the linear rack to move in the direction close to the center of the annular rack, until the arc clamping plate of the second clamping unit clamps the valve seat, and the value collected by the pressure sensor on the arc clamping plate of the second clamping unit reaches the set value, and the controller sends a stop signal to the clamping drive motor of the second clamping unit, and the clamping drive motor of the second clamping unit stops running; S4. Remove the valve cap: Turn on the rotary lifting drive motor, and the rotary lifting drive motor drives the first screw rod to move downward through the second driving gear and the driven gear until the encoder detects the descent to the set distance. At this time, the two semicircular clamping plate covers are arranged on the outside of the valve bonnet, and a stop signal is sent to the rotary lifting drive motor through the controller, and a start signal is sent to the clamping drive motor. The clamping drive motor drives the second screw rod to rotate, and the distance between the two semicircular clamping plates is shortened under the cooperation of the threads until the two semicircular clamping plates clamp the valve bonnet, and the pressure sensor on the semicircular clamping plates detects that the pressure value reaches the set value, and a stop signal is sent to the clamping drive motor through the controller, and a reverse start signal is sent to the rotary lifting drive motor at the same time. The rotary lifting drive motor runs in the reverse direction, driving the first screw rod to rotate upward, and the clamped valve bonnet is removed; S5. Verification: The lifting drive cylinder drives the first clamping unit upward, and then the telescopic drive cylinder drives the second clamping unit to move toward the valve stem until the first clamping unit is located above the valve stem, the telescopic drive cylinder is closed, and the lifting drive cylinder drives the first clamping unit downward until the clamping ring is set on the outside of the valve stem; The clamping drive motor of the first clamping unit is turned on, and the clamping drive motor drives the first drive gear of the first clamping unit to rotate, thereby driving the annular rack of the first clamping unit to rotate horizontally, and then the guide column is used to cooperate with the arc guide groove to drive multiple driven sleeves on the annular rack to rotate synchronously, thereby driving the linear rack to move in the direction close to the center of the annular rack, until the arc clamping plate of the first clamping unit clamps the valve stem, and the value collected by the pressure sensor on the arc clamping plate of the first clamping unit reaches the set value, and a stop signal is sent to the clamping drive motor of the first clamping unit through the controller, and the clamping drive motor of the first clamping unit stops running. At this time, the arc clamping plate is used to limit the valve stem from rotating in the circumferential direction; Open the electric wrench and the lifting drive cylinder of the first clamping unit, the electric wrench screws the nut onto the valve stem, then the clamping drive motor of the first clamping unit rotates in the reverse direction, driving the arc-shaped clamping plate to loosen the valve stem, releasing the circumferential limit of the valve stem, closing the clamping drive motor of the first clamping unit, opening the electric wrench, and driving the nut to rotate in the reverse direction. Under the action of the internal thread of the nut and the external thread of the valve stem, the valve stem is lifted until the first collection peak value is collected by the electric wrench, and the axial tension is calculated using the first collection peak value, and this axial tension is used as the opening pressure of the safety valve; S6, reverse the operation of step S5, remove the first clamping unit, reverse the operation of step S4, install the valve cap, and finally reverse the operation of step S3, remove the second clamping unit, and finally remove the verification device to complete the verification.

10. The method for using the portable safety valve opening pressure calibration device according to claim 9 is characterized in that: In step S5, the calculation formula for calculating the axial tension using the first collected peak value is: T=kdF In the formula, T is the tightening torque, in Nm; F is the axial tension, in N; d is the nominal diameter of the screw, in m; k is the torque coefficient; Push out the axial tension F=T / kd.

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