CN106051240B - Safety valve, the on-line measuring device of safety valve and online test method - Google Patents

Abstract

The invention provides a safety valve, an on-line detection device and an on-line detection method of the safety valve. The side of the valve body is provided with a medium outflow channel communicating with its inner cavity. The bonnet, bonnet, radiator and valve body are fixedly connected from top to bottom in sequence. The valve seat is a three-way structure, and its upper end is a The medium common channel in the body cavity, the lower end and the side are the working medium inflow channel and the detection medium inflow channel connected with the medium common channel, the lower end of the working medium inflow channel is connected with the working pipe through flange sealing, and the mouth of the detection medium inflow channel Equipped with a normally closed detection door. The invention sets a detection medium inflow channel on the valve seat of the safety valve, which can detect the setting pressure, opening pressure, reseating pressure, sealing performance, etc. and other costs, improve work efficiency.

Description

Safety valve, safety valve on-line detection device and on-line detection method

technical field

The invention relates to an overpressure safety protection device for pressure-bearing special equipment such as boilers and pressure vessels, in particular to a safety valve, an on-line detection device and an on-line detection method for the safety valve.

Background technique

The safety valve is the main safety accessory on pressure-bearing special equipment such as filtration and pressure vessels. It is generally installed on equipment in a closed system to protect the safety of the system. When the pressure in the protected equipment exceeds the design pressure, the safety valve will automatically open. Discharge the medium with excessive pressure in the equipment to reduce the pressure in the equipment, so as to avoid the equipment from being damaged by overpressure. When the pressure in the equipment drops to the set pressure, the safety valve will automatically close accordingly, so as to ensure the continuous normal operation of the equipment Work.

According to the provisions of Article B6.3.1 of TSG ZF001-2006 "Safety Valve Safety Technology Supervision Regulations", the safety valve should be checked regularly, generally at least once a year. Periodic calibration of safety valves includes set pressure and sealing pressure tests. The set pressure of the safety valve refers to the predetermined pressure at which the safety valve starts to open under the operating conditions. Under this pressure and the specified operating conditions, the force generated by the medium pressure to open the valve and the force to keep the valve disc on the valve seat are mutually related. Equilibrium, also commonly referred to as cracking pressure. Sealing pressure is the inlet static pressure at which the sealing test is performed, at which pressure the leakage rate through the sealing surface of the closure is measured.

There are many kinds of calibration devices and calibration methods for safety valves. For example, Chinese invention patents CN101329224A and CN101368883A use the displacement of the safety valve stem during the opening process of the safety valve as the criterion for judging the opening state of the safety valve, so as to measure the safety valve. Valve set pressure, cracking pressure, reseating pressure, etc. Another example is the Chinese invention patent CN101403657A, which evaluates the cracking pressure and sealing performance of the safety valve with the leakage of outlet air bubbles. The Chinese invention patents CN104406781A and CN102866008A transmit the displacement of the valve stem, the audio frequency when the disc is opened, or the pressure of the pressure transmitter of the detection device to the control system or the host in the form of electrical signals, which can be intuitively displaced by the operator, The audio or pressure change curve can be used to judge the set pressure and sealing performance of the safety valve. However, when the existing safety valve is tested, the detection medium (pure nitrogen or liquid, etc.) is sent into the safety valve through the working medium inlet channel, and the safety valve needs to be disassembled from its working pipeline for offline detection, and there is no Realize online detection in the true sense, and the cost of disassembly, hoisting, transportation, calibration, and reassembly in the process of centrifugal detection is high, which reduces work efficiency.

Contents of the invention

The technical problem to be solved by the present invention is to provide a safety valve, an on-line detection device and an on-line detection method for the safety valve. The safety valve can be calibrated without disassembly, reducing the cost of disassembly, hoisting and transportation, and improving work efficiency.

In order to solve the above technical problems, an embodiment of the present invention provides a safety valve, which includes a valve body, a valve seat, a valve disc, a recoil disc, a guide sleeve, a radiator, a valve cover, a spring, a valve stem and a valve cap. The side of the valve body is provided with a medium outflow channel communicating with its inner cavity, the guide sleeve is fixed at the opening of the upper part of the valve body, and the valve cap, valve cover, radiator and valve body are fixedly connected in sequence from top to bottom , and the lower end of the radiator is sealingly connected with the upper end surface of the valve body and the guide sleeve;

The valve seat is fixedly connected with the valve body, and its upper end is a medium common channel extending into the inner cavity of the valve body. An adjustment ring is set on the outside of the medium common channel, and the adjustment ring is fixed by an adjustment screw installed on the valve body;

The lower end of the valve disc is pressed against the upper port of the medium common channel, and the upper end of the valve disc is fixedly connected with the recoil disc, and the recoil disc is slid in the center hole of the guide sleeve, and the center hole of the guide sleeve There is a bellows inside, the upper end of the bellows is sealed and pressed between the guide sleeve and the radiator, and the lower end is sealed and welded to the upper surface of the recoil disc;

The side of the recoil disc facing the medium outflow channel is provided with an opening and closing pressure difference adjustment device, and the opening and closing pressure difference adjustment device includes a radial counterbore and a fine-tuning screw arranged on the side of the recoil disc. The radial counterbore is a two-stage structure of an outer light hole and an inner threaded hole, and the light hole diameter is larger than the threaded hole diameter, the head end of the fine-tuning screw is screwed with the threaded hole, and the tail end is located in the light hole;

The upper end of the recoil disc is provided with a valve stem positioning hole, the lower end of the valve stem passing through the valve cover and the radiator is arranged in the valve stem positioning hole, and the upper end extends into the valve cap, and the spring is sleeved on the valve stem The outer side of the spring, the upper and lower ends of the spring are respectively provided with an upper spring seat and a lower spring seat, and the upper spring seat is fixedly connected with the valve cover through a set screw sleeve;

The valve seat is a three-way structure, the lower end and the side of which are respectively the working medium inflow channel and the detection medium inflow channel connected with the medium common channel. The mouth of the detection medium inflow channel is provided with a normally closed detection door, and the working pipes on the left and right sides of the safety valve are respectively provided with cut-off valves.

The embodiment of the present invention also provides another safety valve with basically the same structure, including a valve body, a valve seat, a valve clack, a recoil disc, a guide sleeve, a radiator, a valve cover, a spring, a valve stem and a valve cap. The side of the body is provided with a medium outflow channel communicating with its inner cavity, the guide sleeve is fixed at the opening of the upper part of the valve body, and the valve cap, valve cover, radiator and valve body are fixedly connected sequentially from top to bottom, And the lower end of the radiator is sealingly connected with the upper end surface of the valve body and the guide sleeve;

The valve seat is fixedly connected with the valve body, and its upper end is a medium common channel extending into the inner cavity of the valve body. An adjustment ring is set on the outside of the medium common channel, and the adjustment ring is fixed by an adjustment screw installed on the valve body;

The lower end of the valve disc is pressed against the upper port of the medium common channel, and the upper end of the valve disc is fixedly connected with the recoil disc, and the recoil disc is slid in the center hole of the guide sleeve, and the center hole of the guide sleeve There is a bellows inside, the upper end of the bellows is sealed and pressed between the guide sleeve and the radiator, and the lower end is sealed and welded to the upper surface of the recoil disc;

The side of the recoil disc facing the medium outflow channel is provided with an opening and closing pressure difference adjustment device, and the opening and closing pressure difference adjustment device includes a radial counterbore and a fine-tuning screw arranged on the side of the recoil disc. The radial counterbore is a two-stage structure of an outer light hole and an inner threaded hole, and the light hole diameter is larger than the threaded hole diameter, the head end of the fine-tuning screw is screwed with the threaded hole, and the tail end is located in the light hole;

The upper end of the recoil disc is provided with a valve stem positioning hole, the lower end of the valve stem passing through the valve cover and the radiator is arranged in the valve stem positioning hole, and the upper end extends into the valve cap, and the spring is sleeved on the valve stem The outer side of the spring, the upper and lower ends of the spring are respectively provided with an upper spring seat and a lower spring seat, and the upper spring seat is fixedly connected with the valve cover through a set screw sleeve;

The valve seat is a three-way structure, the lower end and the side of which are respectively the working medium inflow channel and the detection medium inflow channel connected with the medium common channel. A normally closed detection door is provided at the mouth of the detection medium inflow channel, a valve plate is provided at the junction of the working medium inflow channel and the detection medium inflow channel, and a linkage mechanism is provided between the normally closed detection door and the valve plate. The valve plate blocks the inflow channel of the detection medium through the linkage mechanism when the normally closed detection door is closed, and blocks the inflow channel of the working medium when the normally closed detection door is opened.

Wherein, the linkage mechanism is a link mechanism, including a first link, a second link and a third link which are sequentially hinged, the end of the first link is hinged to the normally closed detection door, and the third link is hinged. The end of the connecting rod is hinged with the valve plate.

The embodiment of the present invention also provides an above-mentioned online detection device for a safety valve, which includes a control cabinet, an air storage tank, a cylinder, a water tank and a suction machine. The cover is fixedly connected, the cylinder is provided with a piston rod, the lower end of the piston rod is rigidly connected with the valve rod, and the displacement sensor fixedly connected with the cylinder support through the displacement sensor bracket is provided above the piston rod;

The cylinder is connected to the control cabinet through the upper air intake pipe, the upper air intake pipe is provided with an upper on-off valve and an upper pressure transmitter, and the console is provided with a rising pressure valve and an upper discharge valve for controlling the gas pressure in the upper air intake pipe. Pressure valve;

The gas storage tank is connected to the control cabinet through the main air intake pipe, and the main air intake pipe is provided with a main switch valve;

The control cabinet is connected with the detection medium inflow channel of the safety valve through the lower air inlet pipe and the air inlet pipe joint. The lower air inlet pipe is provided with a lower switch valve and a lower pressure transmitter. Lower pressure boost valve and lower pressure relief valve for gas pressure in the trachea;

The displacement sensor, the upper pressure transmitter and the lower pressure transmitter are all electrically connected to the control cabinet, and the control cabinet is provided with a display screen for displaying the displacement, the upper pressure and the lower pressure;

The medium outflow channel of the safety valve is connected with an air outlet pipe joint, and the air outlet pipe joint is detachably connected to the suction machine through a suction pipe. The suction pipe is provided with a suction valve, and the air outlet pipe joint The air outlet pipe is detachably connected to the water tank, the air outlet pipe is provided with a detection valve, the water tank is provided with pure water, and the end of the air outlet pipe is inserted into the pure water.

Wherein, the gas storage tank, the water tank and the suction machine are placed in an instrument cabinet, the control cabinet is arranged on the upper end surface of the instrument cabinet, sliding wheels are arranged at the lower four corners of the instrument cabinet, the inlet pipe joint, The outlet pipe joint, cylinder, cylinder support, displacement sensor, displacement sensor bracket, and various pipelines are all placed in the instrument cabinet for easy access. Therefore, the online detection device is easy to carry and install, and the detection efficiency is improved.

The embodiment of the present invention also provides an online detection method of a safety valve, comprising the following steps:

(1) Check the safety valve macroscopically, check whether its parts are in good condition, whether there are cracks, rust or mechanical damage;

(2) Open the detection medium inflow channel of the safety valve, block the working medium inflow channel of the safety valve, and connect the online detection device to the safety valve;

(3) Use the suction pipe to connect the suction machine and the outlet pipe joint, open the suction valve on the suction pipe, then open the main switch valve on the main intake pipe and the lower switch valve on the lower intake pipe, and flow into the detection medium Pure nitrogen gas is introduced into the channel, and the nitrogen gas in the lower intake pipe is boosted through the lower booster valve on the console, the valve disc is opened, and the nitrogen gas is kept flowing in for 5 to 8 minutes. , drain the working medium remaining in the safety valve;

(4) Close the main switching valve, the lower switching valve and the suction valve, return the valve disc to the valve seat, and perform a set pressure test after standing still for 2 to 3 minutes;

(5) Open the main switching valve, the upper switching valve and the lower switching valve, and at the same time pressurize the nitrogen in the upper intake pipe and the lower intake pipe through the rising pressure valve and the lower pressure boosting valve on the console. When the pressure rises to At a certain value, under the combined action of the gas pressure in the detection medium flowing into the channel and the pulling force generated by the piston rod on the valve stem, the valve flap opens, and the displacement sensor detects the moment when the valve stem produces an initial displacement, the pressure transmitter and The pressure measured by the upper pressure transmitter after conversion and superposition is the set pressure of the safety valve. If the measured set pressure value is 97%~100% of the theoretical value of the set pressure, the safety valve is qualified. If it is less than 97% of the theoretical value of the set pressure or greater than the theoretical value of the set pressure, the safety valve is damaged and needs to be replaced;

(6) Continue to pressurize the nitrogen in the upper intake pipe and the lower intake pipe so that when the displacement of the valve stem reaches the fully open state of the safety valve, the pressure measured by the lower pressure transmitter and the upper pressure transmitter will be converted and repeated. The added pressure is the opening pressure of the safety valve;

(7) When the valve clack reaches the fully open state, the pressure in the upper intake pipe and the lower intake pipe is released smoothly through the upper pressure relief valve and the lower pressure relief valve, and the valve clack returns to the valve seat. When the displacement of the valve stem returns to At the moment of zero position, the pressure obtained by conversion and superposition of the pressure measured by the lower pressure transmitter and the upper pressure transmitter is the reseating pressure of the safety valve;

(8) Subtract the opening pressure measured in step (6) from the reseating pressure measured in step (7) to obtain the opening and closing pressure difference of the safety valve. If the opening and closing pressure difference of the safety valve does not meet the requirements, turn Fine-tune the screw and repeat steps (5)~(7) until the opening and closing pressure difference reaches the required value. If it still cannot be adjusted to the required range, the safety valve is unqualified and needs to be replaced;

(9) Close the main switching valve, upper switching valve and lower switching valve, and perform a sealing performance test after standing still for 2 to 3 minutes. Use the outlet pipe joint and the outlet pipe to connect the medium outflow channel with the water tank, and open the main switching valve and the lower switching valve. , raise the gas pressure in the lower intake pipe to 90% of the set pressure through the lower pressure boost valve on the console, keep the pressure for 3~5 minutes, observe the number of bubbles in the water tank, for the working medium is flammable, explosive, For toxic and harmful safety valves, it is required to have no leakage within the specified pressure holding time. For non-flammable, explosive, non-toxic and harmful safety valves whose working medium is steam, nitrogen, air, etc., the leakage rate is ≤80 bubbles/min. The performance is qualified, otherwise the safety valve needs to be replaced;

(10) After the inspection is completed, after the pressure in the safety valve is smoothly released to zero through the lower pressure relief valve on the console, the detection device is disassembled from the safety valve, and the safety valve that passes the inspection is hung with a qualification plate, lead seal, issue calibration records and inspection reports, and replace unqualified safety valves.

Wherein, the step (2) of opening the detection medium inflow channel of the safety valve and blocking the working medium inflow channel of the safety valve includes the following steps:

(2-1) Open the normally closed detection door;

(2-2) Close the cut-off valves or normally closed detection doors on the left and right sides of the safety valve on the working pipeline and link the valve plates through the linkage mechanism to block the inflow channel of the working medium.

Connecting the online detection device to the safety valve in step (2) includes the following steps:

(2-3) Install the inlet pipe joint and the air outlet pipe joint at the ends of the detection medium inflow channel and medium outflow channel respectively;

(2-4) Remove the bonnet of the safety valve, fix the cylinder on the bonnet through the cylinder support, and rigidly connect the lower end of the piston rod with the valve stem, and then fix the displacement sensor on the piston rod through the displacement sensor bracket above;

(2-5) Use the main intake pipe, upper intake pipe, and lower intake pipe to connect the air storage tank, intake pipe joint and cylinder with the control cabinet respectively;

(2-6) Use wires to connect the displacement sensor, upper pressure transmitter and lower pressure transmitter to the control cabinet respectively.

Among them, when performing the set pressure detection in step (5), it is also possible to use only one line of the upper intake pipe or the lower intake pipe. At the moment of rod displacement, air bubbles should appear in the tank simultaneously.

The beneficial effects of the above-mentioned technical solution of the present invention are as follows: the present invention sets a detection medium inflow channel on the valve seat of the safety valve, and can detect the setting pressure, opening pressure and reseating pressure of the safety valve online without disassembling the safety valve , sealing performance, etc., reduce disassembly, hoisting, transportation and other costs, and improve work efficiency.

Description of drawings

FIG. 1 is a schematic structural view of Embodiment 1 of the present invention;

FIG. 2 is a schematic structural diagram of Embodiment 2 of the present invention;

FIG. 3 is a schematic structural view of Embodiment 3 of the present invention;

Explanation of reference signs:

1. Valve body; 100, medium outflow channel; 2, valve seat; 200, medium shared channel; 201, working medium inflow channel; 202, detection medium inflow channel; 203, normally closed detection door; 204, valve plate; 205, Linkage mechanism; 3. Disc; 4. Recoil disc; 5. Guide sleeve; 6. Radiator; 7. Valve cover; 8. Spring; 9. Valve stem; 10. Valve cap; 11. Adjusting ring; 12. Adjusting screw; 13, bellows; 14, opening and closing pressure difference adjustment device; 15, upper spring seat; 16, lower spring seat; 17, setting screw sleeve; 18, working pipeline; 19, stop valve; 20, control cabinet; 2000, rising pressure valve; 2001, upper pressure relief valve; 2002, lower pressure relief valve; 2003, lower pressure relief valve; 2004, display screen; 21, gas storage tank; 22, cylinder; 23, sink; 24, suction Machine; 25, cylinder support; 26, piston rod; 27, displacement sensor bracket; 28, displacement sensor; 29, upper intake pipe; 2900, upper switch valve; 2901, upper pressure transmitter; 30, total intake pipe; 3000 , main switch valve; 31, lower intake pipe; 3100, lower switch valve; 3101, lower pressure transmitter; 32, inlet pipe joint; 33, suction pipe; 3300, suction valve; 34, outlet pipe; 3400, Detecting valve; 35, outlet pipe joint.

detailed description

In order to make the technical problems, technical solutions and advantages to be solved by the present invention clearer, the following will describe in detail with reference to the drawings and specific embodiments.

Embodiment 1: As shown in Figure 1, a safety valve includes a valve body 1, a valve seat 2, a valve disc 3, a recoil disc 4, a guide sleeve 5, a radiator 6, a valve cover 7, a spring 8, and a valve stem 9 and a bonnet 10, the side of the valve body 1 is provided with a medium outflow channel 100 communicating with its inner cavity, the guide sleeve 5 is fixed at the opening of the upper part of the valve body 1, the bonnet 10, bonnet 7. The radiator 6 and the valve body 1 are fixedly connected sequentially from top to bottom, and the lower end of the radiator 6 is in sealing connection with the valve body 1 and the upper end surface of the guide sleeve 5 .

The valve seat 2 is fixedly connected with the valve body 1, and its upper end is a medium common channel 200 extending into the inner cavity of the valve body 1. An adjustment ring 11 is set on the outside of the medium common channel 200, and the adjustment ring 11 is installed on the The adjusting screw 12 on the valve body 1 is fixed.

The lower end of the valve disc 3 is pressed against the upper port of the medium common channel 200, the upper end of the valve disc 3 is fixedly connected with the recoil disc 4, and the recoil disc 4 is slidably arranged in the center hole of the guide sleeve 5, The center hole of the guide sleeve 5 is provided with a bellows 13 , the upper end of the bellows 13 is sealed and pressed between the guide sleeve 5 and the radiator 6 , and the lower end is sealed and welded to the upper surface of the recoil disk 4 .

The side of the recoil disk 4 facing the medium outflow channel 100 is provided with an opening and closing pressure difference adjustment device 14, and the opening and closing pressure difference adjustment device includes a radial counterbore and a fine-tuning device arranged on the side of the recoil disk 4. screw, the radial counterbore is a two-stage structure of an outer light hole and an inner threaded hole, and the diameter of the light hole is larger than the diameter of the threaded hole, the head end of the fine-tuning screw is screwed with the threaded hole, and the tail end is located at the light inside the hole.

The upper end of the recoil disk 4 is provided with a valve stem positioning hole, the lower end of the valve stem 9 passing through the valve cover 7 and radiator 6 is arranged in the valve stem positioning hole, and the upper end extends into the valve cap 10, and the spring 8 is sleeved on the outside of the valve stem 9, and the upper and lower ends of the spring 8 are respectively provided with an upper spring seat 15 and a lower spring seat 16, and the upper spring seat 15 is fixedly connected with the valve cover 7 through a set screw sleeve 17.

The valve seat 2 has a three-way structure, and its lower end and sides are respectively the working medium inflow channel 201 and the detection medium inflow channel 202 communicating with the medium common channel 200. The lower end of the working medium inflow channel 201 passes through the working pipeline 18. The flanges are sealed and connected, the mouth of the detection medium inflow channel 202 is provided with a normally closed detection door 203 , and the working pipes 18 on the left and right sides of the safety valve are respectively provided with cut-off valves 19 .

Embodiment 2: As shown in Figure 2, a safety valve includes a valve body, a valve seat, a valve clack, a recoil disc, a guide sleeve, a radiator, a valve cover, a spring, a valve stem and a valve cap, and the valve body The side part of the valve body is provided with a medium outflow channel communicating with its inner cavity, the guide sleeve is fixed at the opening of the upper part of the valve body, and the valve cap, valve cover, radiator and valve body are fixedly connected sequentially from top to bottom, and The lower end of the radiator is in sealing connection with the valve body and the upper end surface of the guide sleeve.

The valve seat is fixedly connected with the valve body, and its upper end is a medium common channel extending into the inner cavity of the valve body. An adjustment ring is set on the outside of the medium common channel, and the adjustment ring is fixed by an adjustment screw installed on the valve body.

The lower end of the valve disc is pressed against the upper port of the medium common channel, and the upper end of the valve disc is fixedly connected with the recoil disc, and the recoil disc is slid in the center hole of the guide sleeve, and the center hole of the guide sleeve A bellows is provided inside, the upper end of the bellows is sealed and pressed between the guide sleeve and the radiator, and the lower end of the bellows is sealed and welded to the upper surface of the recoil disc.

The side of the recoil disc facing the medium outflow channel is provided with an opening and closing pressure difference adjustment device, and the opening and closing pressure difference adjustment device includes a radial counterbore and a fine-tuning screw arranged on the side of the recoil disc. The radial counterbore is a two-stage structure of an outer smooth hole and an inner threaded hole, and the diameter of the smooth hole is larger than that of the threaded hole. The head end of the fine-tuning screw is screwed into the threaded hole, and the tail end is located in the smooth hole.

The upper end of the recoil disc is provided with a valve stem positioning hole, the lower end of the valve stem passing through the valve cover and the radiator is arranged in the valve stem positioning hole, and the upper end extends into the valve cap, and the spring is sleeved on the valve stem The upper and lower ends of the spring are provided with an upper spring seat and a lower spring seat respectively, and the upper spring seat is fixedly connected with the valve cover through a set screw sleeve.

The valve seat is a three-way structure, the lower end and the side of which are respectively the working medium inflow channel and the detection medium inflow channel connected with the medium common channel. The mouth of the detection medium inflow channel 202 is provided with a normally closed detection door 203, a valve plate 204 is provided at the intersection of the working medium inflow channel and the detection medium inflow channel, and a valve plate 204 is provided between the normally closed detection door 203 and the valve plate 204. There is a linkage mechanism 205 through which the valve plate 204 blocks the detection medium inflow channel 202 when the normally closed detection door 203 is closed, and blocks the working medium inflow channel 201 when the normally closed detection door 203 is opened.

The linkage mechanism can adopt any structure that can realize the above-mentioned linkage function. In this embodiment, the linkage mechanism is a linkage mechanism, including a first linkage, a second linkage and a third linkage that are sequentially hinged. The end of the first connecting rod is hinged with the normally closed detection door, and the end of the third connecting rod is hinged with the valve plate.

Embodiment 3: As shown in Figure 3, a kind of on-line detection device of safety valve, comprises control cabinet 20, air storage tank 21, cylinder 22, water tank 23 and suction machine 24, described cylinder 22 is connected with cylinder support 25 The bonnet 7 of the safety valve after the bonnet is removed is fixedly connected, the cylinder 22 is provided with a piston rod 26, the lower end of the piston rod 26 is rigidly connected with the valve rod 9, and the top of the piston rod 26 is provided with a displacement sensor bracket 27 and the displacement sensor 28 that cylinder support 25 is fixedly connected.

The cylinder 22 is connected to the control cabinet 20 through the upper air intake pipe 29, the upper air intake pipe 29 is provided with an upper on-off valve 2900 and an upper pressure transmitter 2901, and the console 20 is provided with a device for controlling the gas pressure in the upper air intake pipe 29. Up pressure valve 2000 and up pressure relief valve 2001.

The gas storage tank 21 is connected to the control cabinet 20 through the main air intake pipe 30, and the main air intake pipe 30 is provided with a main switch valve 3000.

The control cabinet 20 is connected to the detection medium inflow channel 202 of the safety valve through the lower air intake pipe 31 and the air intake pipe joint 32. The lower air intake pipe 31 is provided with a lower switch valve 3100 and a lower pressure transmitter 3101. The control The platform 20 is provided with a lower boost valve 2002 and a lower pressure relief valve 2003 for controlling the gas pressure in the lower intake pipe 31 .

The displacement sensor 28, the upper pressure transmitter 2901 and the lower pressure transmitter 3101 are all electrically connected to the control cabinet 20, and the control cabinet 20 is provided with a display screen for displaying displacement, upper pressure and lower pressure 2004.

The medium outflow channel 100 of the safety valve is connected with an air outlet pipe joint 35, the air outlet pipe joint 32 is detachably connected with the suction machine 24 through a suction pipe 33, and the suction pipe 33 is provided with a suction valve 3300, the air outlet pipe joint 32 is detachably connected to the water tank 23 through the air outlet pipe 34, the air outlet pipe 34 is provided with a detection valve 3400, the water tank 23 is provided with pure water, and the end of the air outlet pipe 34 Insert into purified water.

The gas storage tank 21 of the present embodiment, the water tank 23 and the suction machine 24 are preferably placed in an instrument cabinet, and the control cabinet 20 is arranged on the upper end surface of the instrument cabinet, and sliding wheels are provided at the four corners below the instrument cabinet to carry out Air pipe joints, air outlet pipe joints, cylinders, cylinder supports, displacement sensors, displacement sensor brackets, and various pipelines are all placed in the instrument cabinet where they are easy to pick and place. Therefore, the online detection device is easy to carry and install, and improves detection. efficiency.

The method for performing on-line detection of the safety valve by using the above-mentioned on-line detection device includes the following steps:

(1) Check the safety valve macroscopically, check whether its parts are in good condition, whether there are cracks, rust or mechanical damage;

(2) Open the detection medium inflow channel of the safety valve, block the working medium inflow channel of the safety valve, and connect the online detection device to the safety valve;

The specific steps are:

(2-1) Open the normally closed detection door;

(2-2) Close the cut-off valves or normally closed detection doors on the left and right sides of the safety valve on the working pipeline and link the valve plates through the linkage mechanism to block the inflow channel of the working medium;

(2-3) Install the inlet pipe joint and the air outlet pipe joint at the ends of the detection medium inflow channel and medium outflow channel respectively;

(2-4) Remove the bonnet of the safety valve, fix the cylinder on the bonnet through the cylinder support, and rigidly connect the lower end of the piston rod with the valve stem, and then fix the displacement sensor on the piston rod through the displacement sensor bracket above;

(2-5) Use the main intake pipe, upper intake pipe, and lower intake pipe to connect the air storage tank, intake pipe joint and cylinder with the control cabinet respectively;

(2-6) Use wires to connect the displacement sensor, upper pressure transmitter and lower pressure transmitter to the control cabinet respectively.

(3) Use the suction pipe to connect the suction machine and the outlet pipe joint, open the suction valve on the suction pipe, then open the main switch valve on the main intake pipe and the lower switch valve on the lower intake pipe, and flow into the detection medium Pure nitrogen gas is introduced into the channel, and the nitrogen gas in the lower intake pipe is boosted through the lower booster valve on the console, the valve disc is opened, and the nitrogen gas is kept flowing in for 5 to 8 minutes. , drain the working medium remaining in the safety valve;

(4) Close the main switching valve, the lower switching valve and the suction valve, return the valve disc to the valve seat, and perform a set pressure test after standing still for 2 to 3 minutes;

(5) Open the main switching valve, the upper switching valve and the lower switching valve, and at the same time pressurize the nitrogen in the upper intake pipe and the lower intake pipe through the rising pressure valve and the lower pressure boosting valve on the console. When the pressure rises to At a certain value, under the combined action of the gas pressure in the detection medium flowing into the channel and the pulling force generated by the piston rod on the valve stem, the valve flap opens, and the displacement sensor detects the moment when the valve stem produces an initial displacement, the pressure transmitter and The pressure measured by the upper pressure transmitter after conversion and superposition is the set pressure of the safety valve. If the measured set pressure value is 97%~100% of the theoretical value of the set pressure, the safety valve is qualified. If it is less than 97% of the theoretical value of the set pressure or greater than the theoretical value of the set pressure, the safety valve is damaged and needs to be replaced;

Among them, when performing the set pressure detection in this step (5), it is also possible to use only one line of the upper intake pipe or the lower intake pipe. At the moment of the displacement of the valve stem, air bubbles should appear in the water tank simultaneously.

(6) Continue to pressurize the nitrogen in the upper intake pipe and the lower intake pipe so that when the displacement of the valve stem reaches the fully open state of the safety valve, the pressure measured by the lower pressure transmitter and the upper pressure transmitter will be converted and repeated. The added pressure is the opening pressure of the safety valve;

(7) When the valve clack reaches the fully open state, the pressure in the upper intake pipe and the lower intake pipe is released smoothly through the upper pressure relief valve and the lower pressure relief valve, and the valve clack returns to the valve seat. When the displacement of the valve stem returns to At the moment of zero position, the pressure obtained by conversion and superposition of the pressure measured by the lower pressure transmitter and the upper pressure transmitter is the reseating pressure of the safety valve;

(8) Subtract the opening pressure measured in step (6) from the reseating pressure measured in step (7) to obtain the opening and closing pressure difference of the safety valve. If the opening and closing pressure difference of the safety valve does not meet the requirements, turn Fine-tune the screw and repeat steps (5)~(7) until the opening and closing pressure difference reaches the required value. If it still cannot be adjusted to the required range, the safety valve is unqualified and needs to be replaced;

(9) Close the main switching valve, upper switching valve and lower switching valve, and perform a sealing performance test after standing still for 2 to 3 minutes. Use the outlet pipe joint and the outlet pipe to connect the medium outflow channel with the water tank, and open the main switching valve and the lower switching valve. , raise the gas pressure in the lower intake pipe to 90% of the set pressure through the lower pressure boost valve on the console, keep the pressure for 3~5 minutes, observe the number of bubbles in the water tank, for the working medium is flammable, explosive, For toxic and harmful safety valves, it is required to have no leakage within the specified pressure holding time. For non-flammable, explosive, non-toxic and harmful safety valves whose working medium is steam, nitrogen, air, etc., the leakage rate is ≤80 bubbles/min. The performance is qualified, otherwise the safety valve needs to be replaced;

(10) After the inspection is completed, after the pressure in the safety valve is smoothly released to zero through the lower pressure relief valve on the console, the detection device is disassembled from the safety valve, and the safety valve that passes the inspection is hung with a qualification plate, lead seal, issue calibration records and inspection reports, and replace unqualified safety valves.

The invention sets a detection medium inflow channel on the valve seat of the safety valve, which can detect the setting pressure, opening pressure, reseating pressure, sealing performance, etc. and other costs, improve work efficiency.

The above description is a preferred embodiment of the present invention, it should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, some improvements and modifications can also be made, and these improvements and modifications can also be made. It should be regarded as the protection scope of the present invention.

Claims (8)

1. a kind of safety valve, it is characterised in that including valve body, valve seat, flap, Disc holder, guide sleeve, radiator, bonnet, bullet Spring, valve rod and bonnet, the sidepiece of the valve body are provided with the medium flow pass connected with its inner chamber, and the guide sleeve is fixedly arranged on valve The opening on body top, the bonnet, bonnet, radiator and valve body are fixedly connected sequentially from top to bottom, and the radiator Lower end and the upper surface of valve body, guide sleeve are tightly connected；

The valve seat is fixedly connected with the valve body, and its upper end is the medium common-use tunnel for stretching into body cavity, and the medium shares logical The outer sheath in road is equipped with adjusting ring, and the adjusting ring is fixed by the adjusting screw on valve body；

The lower end of the flap presses on medium common-use tunnel upper end oral area, and the upper end of the flap is fixedly connected with Disc holder, The Disc holder is slidedly arranged in the centre bore of guide sleeve, is provided with bellows in the guide sleeve centre bore, the bellows it is upper End sealing is fitted between guide sleeve and radiator, the upper surface sealing welding of lower end and Disc holder；

The Disc holder is provided with blowdown of a safety valve adjusting means, the blowdown of a safety valve regulation dress in face of the side of medium flow pass Put including the radial direction counterbore and micrometer adjusting screw located at Disc holder side, the radial direction counterbore is outer section of unthreaded hole and inner segment screwed hole Two-part structure, and unthreaded hole aperture is more than screwed hole aperture, the head end and screw hole of the micrometer adjusting screw, tail end is located at light In hole；

The upper end of the Disc holder is provided with valve rod positioning hole, determines through the lower end of the bonnet and the valve rod of radiator located at valve rod In the hole of position, upper end is stretched into bonnet, and the spring housing is located at the outside of valve rod, and the upper and lower side of the spring is respectively equipped with spring Seat and lower spring cup, the upper spring seat are fixedly connected by adjusting swivel nut with bonnet；

The valve seat is three-port structure, and its lower end and side are respectively the working media flow channel connected with medium common-use tunnel With detection medium flow channel, the lower end of the working media flow channel is connected with service pipe by flange seal, described The oral area of detection medium flow channel is provided with normally closed detection door, is respectively equipped with the service pipe at left and right sides of the safety valve section Only valve.

2. a kind of safety valve, it is characterised in that including valve body, valve seat, flap, Disc holder, guide sleeve, radiator, bonnet, bullet Spring, valve rod and bonnet, the sidepiece of the valve body are provided with the medium flow pass connected with its inner chamber, and the guide sleeve is fixedly arranged on valve The opening on body top, the bonnet, bonnet, radiator and valve body are fixedly connected sequentially from top to bottom, and the radiator Lower end and the upper surface of valve body, guide sleeve are tightly connected；

The valve seat is fixedly connected with the valve body, and its upper end is the medium common-use tunnel for stretching into body cavity, and the medium shares logical The outer sheath in road is equipped with adjusting ring, and the adjusting ring is fixed by the adjusting screw on valve body；

The lower end of the flap presses on medium common-use tunnel upper end oral area, and the upper end of the flap is fixedly connected with Disc holder, The Disc holder is slidedly arranged in the centre bore of guide sleeve, is provided with bellows in the guide sleeve centre bore, the bellows it is upper End sealing is fitted between guide sleeve and radiator, the upper surface sealing welding of lower end and Disc holder；

The Disc holder is provided with blowdown of a safety valve adjusting means, the blowdown of a safety valve regulation dress in face of the side of medium flow pass Put including the radial direction counterbore and micrometer adjusting screw located at Disc holder side, the radial direction counterbore is outer section of unthreaded hole and inner segment screwed hole Two-part structure, and unthreaded hole aperture is more than screwed hole aperture, the head end and screw hole of the micrometer adjusting screw, tail end is located at light In hole；

The upper end of the Disc holder is provided with valve rod positioning hole, determines through the lower end of the bonnet and the valve rod of radiator located at valve rod In the hole of position, upper end is stretched into bonnet, and the spring housing is located at the outside of valve rod, and the upper and lower side of the spring is respectively equipped with spring Seat and lower spring cup, the upper spring seat are fixedly connected by adjusting swivel nut with bonnet；

The valve seat is three-port structure, and its lower end and side are respectively the working media flow channel connected with medium common-use tunnel With detection medium flow channel, the lower end of the working media flow channel is connected with service pipe by flange seal, described The oral area of detection medium flow channel is provided with normally closed detection door, and the working media flow channel and detection medium flow channel are handed over Meet place and be provided with valve block, be provided with link gear between the normally closed detection door and valve block, the valve block is by link gear in normally closed Detect closure detection medium flow channel when door is closed, block working media flow channel when normally closed detection door is opened.

3. safety valve according to claim 2, it is characterised in that the link gear is linkage, including is cut with scissors successively First connecting rod, second connecting rod and the third connecting rod connect, the end of the first connecting rod connect with normally closed detection door hinge, and the described 3rd connects The end of bar is hinged with valve block.

4. the on-line measuring device of a kind of safety valve as any one of claim 1 ~ 3, it is characterised in that including control Cabinet, air accumulator, cylinder, tank and suction machine, the cylinder are consolidated by the bonnet of cylinder saddle and the safety valve after removal bonnet Fixed connection, the cylinder is interior to be provided with piston rod, and lower end and the valve rod of piston rod are rigidly connected, and the top of the piston rod, which is provided with, to be led to Cross the displacement transducer that displacement sensor bracket is fixedly connected with cylinder saddle；

The cylinder is connected by enterprising tracheae with switch board, and the enterprising tracheae is provided with upper switch valve and upper pressure inverting Device, the console are provided with the upper back-up valve for controlling enterprising tracheal strips gas pressure and upper relief valve；

The air accumulator is connected by total inlet pipe with switch board, and the total inlet pipe is provided with switch valve；

The switch board is connected by lower inlet duct and air inlet pipe joint with the detection medium flow channel of safety valve, is entered under described Tracheae is provided with lower switch valve and lower pressure transmitter, and the console is provided with the lower liter of gas pressure in control lower inlet duct Pressure valve and lower relief valve；

Institute's displacement sensors, upper pressure transmitter and lower pressure transmitter are electrically connected with switch board, on the switch board Provided with display displacement, upper amount of pressure and push show of strength screen；

Outlet pipe joint is connected with the medium flow pass of the safety valve, the outlet pipe joint passes through suction tube and suction Machine detachable connection, the suction tube are provided with suction valve, and the outlet pipe joint is detachable with tank by escape pipe Connection, the escape pipe are provided with detection valve, and pure water, the end insertion pure water of the escape pipe are provided with the tank It is interior.

5. the on-line measuring device of safety valve according to claim 4, it is characterised in that the air accumulator, tank and take out Suction machine is placed in an instrument cabinet, and the switch board is provided with the upper surface of instrument cabinet at the four corners below of the instrument cabinet Movable pulley.

6. a kind of online test method of safety valve, it is characterised in that comprise the following steps：

（1）Macro -graph safety valve, check whether its parts is intact, there is flawless, corrosion or mechanical damage；

（2）The detection medium flow channel to open the safety-valve, blocks the working media flow channel of safety valve, on-line checking is filled Put connection corresponding with safety valve；

（3）Suction machine and outlet pipe joint are connected using suction tube, the suction valve on suction tube is opened, then opens total inlet pipe On switch valve and lower inlet duct on lower switch valve, be passed through pure nitrogen into detection medium flow channel, and pass through Lower back-up valve on console boosts to the nitrogen in lower inlet duct, opens flap, and holding is passed through nitrogen 5 ~ 8 minutes, Under the collective effect of suction machine, the working media emptying that will remain in safety valve；

（4）Close switch valve, lower switch valve and suction valve, flap to return on valve seat, after static 2 ~ 3 minutes, carry out adjusting pressure Power is tested；

（5）Switch valve, upper switch valve and lower switch valve are opened, while passes through the upper back-up valve on console and lower back-up valve pair Nitrogen in enterprising tracheae and lower inlet duct is pressurizeed, when pressure rise is to some value, in detection medium flow channel The synergy to pulling force caused by valve rod of gas pressure and piston rod under, flap is opened, and displacement transducer detects valve rod The moment of initial displacement is produced, the pressure that the pressure that lower pressure transmitter and upper pressure transmitter measure obtains by conversion superposition It is then the set-pressure of safety valve, if the set-pressure value measured is the 97% ~ 100% of set-pressure theoretical value, safety valve closes Lattice, carry out following detecting step, if less than set-pressure theoretical value 97% or more than set-pressure theoretical value, safety valve It has been damaged that, need to change；

（6）Continue to pressurize to the nitrogen in enterprising tracheae and lower inlet duct, the displacement of valve rod is reached the standard-sized sheet of safety valve When opening state, the pressure that pressure that lower pressure transmitter and upper pressure transmitter measure obtains by conversion superposition is then safety valve Opening pressure；

（7）After flap reaches full open state, by upper relief valve and lower relief valve by enterprising tracheae and lower inlet duct The steady release of pressure, flap are returned on valve seat, and when the displacement of valve rod returns to the moment of zero-bit, lower pressure transmitter and upper pressure become Send blow pressure of the pressure that device measures by the pressure obtained by conversion superposition is exactly safety valve；

（8）By step（6）In the Opening pressure and step that measure（7）The blow pressure measured, which subtracts each other, produces safety valve blowdown of a safety valve Value, if safety valve blowdown of a safety valve value is unsatisfactory for requiring, rotary fine adjustment screw, repeat step（5）~（7）, until blowdown of a safety valve value reaches To requiring, if can not be adjusted to all the time in claimed range, safety valve is unqualified, needs to change；

（9）Switch valve, upper switch valve and lower switch valve are closed, sealing property test is carried out after static 2 ~ 3 minutes, utilizes outlet Pipe joint and escape pipe connect medium flow pass with tank, switch valve and lower switch valve are opened, by console Gas pressure in lower inlet duct is increased to the 90% of set-pressure by lower back-up valve, pressurize 3 ~ 5 minutes, observes the gas in tank Number is steeped, is inflammable and explosive, poisonous and hazardous safety valve for working media, it is desirable to the No leakage within the defined dwell time, it is right Safety valve in working media for non-flammable explosive, non-toxicity harmful steam, nitrogen or air, slip≤80 bubbles/minute, Then sealing property is qualified, otherwise needs to change safety valve；

（10）After being verified, by the lower relief valve on console by after the steady pressure release of pressure to the zero-bit in safety valve, incite somebody to action Detection means disassembles from safety valve, to examining qualified safety valve to hang approval plate, lead sealing, providing calibration tails and inspection Report, is changed to underproof safety valve.

7. the online test method of safety valve according to claim 6, it is characterised in that step（2）In opening safety The detection medium flow channel of valve, blocks the working media flow channel of safety valve, comprises the following steps：

（2-1）Open normally closed detection door；

（2-2）Close the shutoff valve on service pipe at left and right sides of safety valve or normally closed detection door is joined by link gear Moving valve plate is to block working media flow channel.

8. the online test method of safety valve according to claim 6, it is characterised in that step（2）In will examine online Survey device and be attached with safety valve and comprised the following steps：

（2-3）Air inlet pipe joint and outlet pipe joint are arranged on to the end of detection medium flow channel and medium flow pass respectively Portion；

（2-4）Take away the bonnet of safety valve, cylinder be fixedly connected on bonnet by cylinder saddle, the lower end of its piston rod with Valve rod is rigidly connected, then displacement transducer is fixed on to the top of piston rod by displacement sensor bracket；

（2-5）Air accumulator, the gentle cylinder of air inlet pipe joint and switch board are distinguished using total inlet pipe, enterprising tracheae, lower inlet duct Connection；

（2-6）Displacement transducer, upper pressure transmitter and lower pressure transmitter are connected with switch board respectively using wire.