A pull-off interlock protector

Abstract

The utility model relates to natural gas transportation technical field, the utility model provides a kind of pull-off interlock protector, a kind of pull-off interlock protector, including pull-off valve, the module being equipped with outside pull-off valve, the intermediate relay module is hung in the lower portion of the module, the intermediate relay module is connected with PLC central console, the module includes outer end and fixed end, the fixed end is set in the first end of the pull-off valve, the outer end is set in the second end of the pull-off valve, multiple positioning screws are worn in the outer end, multiple proximity switches are worn in the fixed end, the proximity switch is used to detect the distance change of corresponding positioning screw and proximity switch, each the proximity switch is mutually connected with intermediate relay module and forms closed loop, the PLC central console is used to detect whether the intermediate relay module is disconnected, when the PLC central console detects that intermediate relay module is disconnected, sends parking instruction.

Description

Technical Field

[0001] This utility model relates to the field of natural gas transportation technology, specifically a breakage interlocking protector. Background Technology

[0002] When a liquefied natural gas (LNG) loading / unloading pipeline is pulled out or broken, pipeline facilities equipped with breakaway valves can only suppress the leak, without triggering an interlocking shutdown command for the loading / unloading system. This could further damage the pipeline setup or other pressurization devices, and cause the breakaway valve to fail. Currently, most shutdowns rely on manual operation; that is, operators manually shut down the equipment when they observe a leak at the breakaway valve site or when a combustible gas alarm is triggered. This not only consumes more time, but improper shutdown procedures or failure to shut down the equipment in a timely manner could lead to greater fire hazards and casualties. Utility Model Content

[0003] This utility model provides a breakage interlock protector, the purpose of which is to solve the technical problems in the prior art.

[0004] This utility model provides a pull-out interlock protector, including a module installed outside the pull-out valve, an intermediate relay module mounted below the module, the intermediate relay module being connected to a PLC control console, the PLC control console being used to detect whether the intermediate relay module is disconnected, and sending a stop command when the PLC control console detects that the intermediate relay module is disconnected;

[0005] The module includes an outer end and a fixed end. The fixed end is sleeved on the first end of the breakaway valve, and the outer end is sleeved on the second end of the breakaway valve. Multiple positioning screws are inserted inside the outer end, and multiple proximity switches are inserted inside the fixed end. The proximity switches are used to detect the change in distance between the corresponding positioning screw and the proximity switch. Each proximity switch SQ is connected in series with the intermediate relay module to form a closed loop.

[0006] Furthermore, the outer end is a circular metal ring, and the outer end is axially provided with a plurality of first threaded holes, each of the positioning screws passing through the corresponding first threaded hole, and the first threaded hole is a through hole.

[0007] Furthermore, the outer end side surface is provided with a plurality of second threaded holes, each second threaded hole communicating with a corresponding first threaded hole, and a fixing screw passing through the second threaded hole, the fixing screw being used to abut against the side surface of the positioning screw and lock the positioning screw.

[0008] Furthermore, the fixed end is provided with a plurality of through slots in the axial direction, the through slots are connected to the first threaded hole, the proximity switch passes through the through slots, and the horizontal projection of the proximity switch coincides with the horizontal projection of the positioning screw.

[0009] Furthermore, an annular groove is provided in the fixed end, the annular groove is connected to each of the through grooves, each proximity switch is connected in series, the wires between the proximity switches are passed through the annular groove, and two wire ports connected to the annular groove are provided on the side surface of the fixed groove, the wires are passed into or out of the wire ports.

[0010] Furthermore, a gap is provided between the fixed end and the outer end, and a partition is provided in the gap. The partition is used to hang on the pull-off valve, and the two sides of the partition are used to abut against the positioning screw and the proximity switch, respectively.

[0011] Furthermore, the intermediate relay module is provided with a self-locking circuit, which includes a first button, an indicator light, and a self-locking coil. The indicator light is connected in parallel with a plurality of proximity switches connected in series. One end of the parallel connection between the indicator light and the plurality of proximity switches is connected in series with the positive terminal, and the other end of the parallel connection between the indicator light and the plurality of proximity switches is connected in series with the first button. The first button is connected in series with the negative terminal and is used to activate the intermediate relay module.

[0012] Furthermore, a second button is connected in series between the first button and the positive terminal. The second button is used to detect whether the PLC system alarms when the circuit is disconnected.

[0013] Furthermore, the proximity switch is an intrinsically safe explosion-proof proximity switch.

[0014] This utility model has at least the following beneficial effects:

[0015] This utility model provides a pull-off interlock protector. When the pull-off valve is pulled by an external force and breaks or does not break completely, the distance between any of the positioning screws and the proximity switch changes. When the actual distance is greater than the detected distance, the intermediate relay module alarms and issues a stop command to close all process valves to ensure on-site safety. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of a pull-off interlocking protector according to the present invention;

[0017] Figure 2 This is a schematic diagram of the intermediate relay module circuit of a pull-off interlocking protector according to the present invention;

[0018] Figure 3 This is a cross-sectional view of the fixed end of a pull-out interlock protector according to the present invention;

[0019] Figure 4This is a half-sectional view of the outer end of a pull-out interlock protector according to the present invention;

[0020] In the diagram: SB1, first button; SB2, second button; D1, indicator light; SQ, proximity switch; KA, intermediate relay module coil; 2, outer end; 3, fixed end; 4, first threaded hole; 5, through slot; 6, positioning screw; 7, annular slot; 8, wire port; 9, gap; 10, hinge; 11, clip; 12, second threaded hole; 13, fixing screw. Detailed Implementation

[0021] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0022] Please see Figures 1-4 This utility model provides a pull-out interlock protector, including an intermediate relay module and a module; a pull-out valve is installed inside the module, the intermediate relay module is connected to the module, and the module is sleeved on the outside of the pull-out valve. The intermediate relay module is connected to a PLC control panel.

[0023] The module includes a fixed end 3 and an outer end 2. Both the fixed end 3 and the outer end 2 are annular metal rings. The input end of the fixed end 3 is sleeved on the first end of the breakaway valve, and the output end of the fixed end 3 abuts against the input end of the outer end 2. The side of the outer end 2 away from the fixed end 3 is sleeved on the second end of the breakaway valve. The side of the first end of the breakaway valve away from the fixed end 3 is connected to the unloading platform or the gas dispenser, and the second end of the breakaway valve is connected to the gas dispensing equipment.

[0024] The outer end 2 has multiple axially formed first threaded holes 4, each of which is arranged in a ring array. Each first threaded hole 4 is evenly opened on the outer end 2. The first threaded hole 4 is a through hole, and each first threaded hole 4 is connected by a thread.

[0025] Multiple through slots 5 are axially formed within the fixed end 3. Each through slot 5 corresponds to and communicates with each of the first threaded holes 4. A proximity switch SQ is installed within each through slot 5. The through slot 5 and the proximity switch SQ are used to detect the distance between the proximity switch SQ and the positioning screw 6. The four proximity switches SQ are connected in series. An annular groove 7 is formed within the fixed end 3, communicating with each of the through slots 5. A wire connected in series between each proximity switch SQ is placed within the annular groove 7. Two wire ports 8 are formed on the side wall surface of the fixed end 3, communicating with the annular groove 7. The wire ports 8 are used for inserting and exiting wires, which are connected to the intermediate relay module. Each proximity switch SQ is connected in series and forms a closed loop with the intermediate relay module. The PLC control panel detects whether the closed loop is broken. When the PLC control panel detects that the closed loop is broken, it sends a stop command. The direct linkage between the intermediate relay module and the PLC control panel realizes fully automated protection from detection to execution. Once triggered, the system automatically shuts down all relevant equipment and valves without manual intervention, offering rapid response and decisive handling, significantly enhancing on-site safety in emergency situations. Four proximity switches (SQ) arranged in a ring array on the module provide comprehensive, multi-point monitoring of the breakaway valve. Regardless of the direction of the external force, as long as displacement occurs in any direction of the valve body, at least one proximity switch (SQ) will be triggered. An annular groove (7) inside the fixed end (3) accommodates the series wires between the proximity switches (SQ), ensuring neat and protected wiring, preventing wear or damage that could be caused by exposed wiring, and improving the overall durability of the system.

[0026] In an embodiment of this utility model, the intermediate relay module includes an indicator light D1, a first button SB1, and a second button SB2. The alarm indicator light D1 is connected in parallel with each of the proximity switches SQ, and the first button SB1 is connected in series with a coil KA. The indicator light D1 and the proximity switches SQ are connected in series with the first button SB1. The proximity switches SQ and the indicator light D1 are connected to the positive terminal, and the first button SB1 is connected to the negative terminal. The first button SB1 is located at the normally open point of the coil KA. SB1 is specifically a normally open switch. When any of the proximity switches SQ detects a change in the distance of the positioning screw 6, the closed circuit is broken, the indicator light D1 stops illuminating, and the PLC control panel detects the circuit break and sends a stop command to other facilities to shut down the equipment. How the PLC control panel detects the open circuit of the proximity switches SQ is existing technology and will not be described in detail here. The four proximity switches SQ are connected in series. The advantage of this design is that if any proximity switch SQ detects an excessive distance (i.e., a circuit break), the entire series circuit will be immediately interrupted. After the PLC control panel detects the circuit break, it will immediately execute the stop command. This "one-vote veto" logic ensures the immediacy and certainty of the response, eliminating the risk of system failure due to a single point of failure.

[0027] Four proximity switches SQ form a series circuit. When the power is on, pressing the SB1 button connects the circuit, the normally open contact of the intermediate relay forms a self-locking connection with SB1, the D1 indicator light illuminates, and the system operates normally. When the breakaway valve is broken by external force or not completely broken, the proximity switch installed at the fixed end of the breakaway valve detects a change in the distance to any of the positioning screws at the outer end. At this time, the proximity switch changes from the closed state to the open state, and the power supply to the circuit is interrupted. The intermediate relay module is connected to the PLC cabinet. If the system is set to have a power failure alarm and stop function, the stop command will be executed.

[0028] As an optional embodiment, there is a gap 9 between the outer end 2 and the fixed end 3, the gap 9 being 0.5mm-0.8mm.

[0029] As an implementable example, a partition is provided between the outer end 2 and the fixed end 3. The partition has an opening in the middle, which is attached to the pull-off valve. The positioning screw facing the outer end 2 abuts against the partition. When monitoring of the pull-off valve needs to be started, the partition is pulled out and the first button SB1 is opened. Using a 0.5mm-0.8mm partition as a standard gasket during installation allows for precise and uniform setting of the initial gap between the fixed end 3 and the outer end 2. This standardized operation ensures that each set of equipment has the same accurate detection sensitivity after installation, eliminating performance differences caused by human installation errors.

[0030] In this embodiment of the invention, hinges 10 are fixedly connected to the top of both the outer end 2 and the fixed end 3. Both the outer end 2 and the fixed end 3 are openable circular fasteners. Clamping pieces 11 are fixedly connected to the bottom of both the outer end 2 and the fixed end 3. The clamping pieces 11 are locked with bolts and nuts to prevent slippage. Since both the fixed end 3 and the outer end 2 are designed as openable circular fasteners (connected by hinges 10 and locked with bolts), installation does not require disassembly of pipelines or breakaway valves. They can be directly fitted onto the corresponding position of the breakaway valve like a clamp and locked, greatly simplifying the installation and disassembly process and facilitating later maintenance and repair.

[0031] In an embodiment of this utility model, a plurality of second threaded holes 12 are provided on the outer end 2 side surface. Each second threaded hole 12 communicates with a corresponding first threaded hole 4. Each second threaded hole 12 is radially arranged and perpendicular to the first threaded hole 4. A fixing screw 13 is threadedly connected to each second threaded hole 12. The fixing screw 13 is used to abut against the positioning screw 6 to prevent the positioning screw 6 from moving due to vibration or other reasons, thus preventing false detection by the proximity switch SQ. It is used to radially abut against and lock the positioning screw 6. This design can effectively prevent the positioning screw 6 from loosening or shifting due to vibration generated by equipment (such as pumps, compressors) operation or vehicle movement, thereby avoiding false detection and false alarms by the proximity switch SQ, and ensuring the continuity and stability of production.

[0032] As an example of implementation, the first button SB1 is connected in series with a second button SB2, which is connected in series between the negative terminal and the first button SB1. The second button SB2 is used to test the indicator light D1.

[0033] The working process of this utility model is as follows: the outer end 2 and the fixed end 3 of the module are respectively installed at the corresponding positions of the breakaway valve, and the first threaded hole 4 is aligned with the through hole. During installation, a 0.5mm-0.8mm partition is used as the standard for measuring the distance between the two modules to ensure that the equipment can operate normally.

[0034] During installation and use, ensure the four positioning screws 6 are evenly pressed against the partition. After installation, remove the partition. When all four proximity switches SQ detect the outer two positioning screws 6, the circuit remains unobstructed. With power on, press the first button SB1. At this time, the relay circuit self-locks, the entire circuit forms a loop, indicator light D1 illuminates, and the equipment operates normally. When the breakaway valve is pulled by external force, if it breaks or does not break completely, the distance between any one of the positioning screws 6 and the proximity switch SQ changes. When the actual distance is greater than the detected distance, the intermediate relay module alarms, issuing a stop command to close all process valves to ensure on-site safety.

[0035] Material selection:

[0036] All metal parts and screws in the module are made of stainless steel, which can withstand low temperatures to ensure the equipment remains intact.

[0037] The proximity switch SQ is a rotary electromagnetic ultra-short intrinsically safe explosion-proof proximity switch SQ. In actual production, the intrinsically safe explosion-proof proximity switch SQ model KJT-NJ-4 from KJT was selected for this product. It has a small installation distance and a size of only φ4*8mm.

[0038] This model of proximity switch SQ is intrinsically safe and has explosion-proof performance;

[0039] The SQ model proximity switch has a precise and minute detection distance, capable of detecting distance changes of 0.8mm-1mm;

[0040] This model of proximity switch, SQ, operates at a voltage of 6V-24V and uses a 2M intrinsically safe cable for wiring.

[0041] The operating temperature range of this model of proximity switch SQ is -40℃ to 80℃. It is intrinsically safe and explosion-proof. In the operation of LNG equipment, there is a large temperature difference between the outside temperature of the break-off valve and the height of the break-off valve. Therefore, keeping the detection switch 8mm away from the outside of the break-off valve will not affect its operation.

[0042] Four proximity switches SQ can effectively detect the distance between the four positioning screws 6 connected to the equipment, preventing the pull-off valve from being completely disconnected. Even if there is only a crack, it can still play a role in triggering an alarm by detecting a small change in the distance.

[0043] The intrinsically safe explosion-proof proximity switch SQ (such as KJT-NJ-4) used can detect minute distance changes of 0.8mm-1mm. This means that when the breakaway valve is pulled by external force, even if it only develops a tiny crack or slight displacement and has not yet completely disconnected, the protector can immediately detect the change in distance between the positioning screw 6 and the proximity switch SQ. This ability to alarm even when the valve is "cracked but not completely disconnected" significantly advances the safety threshold. The system can issue a shutdown command and close the process valves at the first sign of a potential leak, thereby effectively preventing major accidents such as material (e.g., LNG) leaks, fires, and explosions, minimizing safety risks.

Claims

1. A breakage interlock protector, characterized in that, The system includes a module fitted over a breakaway valve, with an intermediate relay module mounted below the module, and the intermediate relay module connected to a PLC control panel. The module includes an outer end (2) and a fixed end (3). The fixed end (3) is sleeved on the first end of the break-off valve, and the outer end (2) is sleeved on the second end of the break-off valve. Multiple positioning screws (6) are inserted inside the outer end (2), and multiple proximity switches (SQ) are inserted inside the fixed end (3). The proximity switches (SQ) are used to detect the change in distance between the corresponding positioning screw (6) and the proximity switch (SQ). Each proximity switch (SQ) is connected in series with each other and forms a closed loop with the intermediate relay module. The PLC central control console is used to detect whether the closed loop is broken. When the PLC central control console detects that the closed loop is broken, it sends a stop command.

2. The pull-out interlock protector according to claim 1, characterized in that, The outer end (2) is a circular metal ring, and the outer end (2) is provided with a plurality of first threaded holes (4) in the axial direction. Each positioning screw (6) passes through the corresponding first threaded hole (4), and the first threaded hole (4) is a through hole.

3. A pull-out interlock protector according to claim 2, characterized in that, The outer end (2) side surface is provided with a plurality of second threaded holes (12), each second threaded hole (12) is connected to the corresponding first threaded hole (4), and a fixing screw (13) is inserted in the second threaded hole (12). The fixing screw (13) is used to abut against the side surface of the positioning screw (6) and lock the positioning screw (6).

4. A pull-out interlock protector according to claim 2, characterized in that, The fixed end (3) has a plurality of through slots (5) axially. The through slots (5) are connected to the first threaded hole (4). The proximity switch SQ passes through the through slots (5). The horizontal projection of the proximity switch SQ coincides with the horizontal projection of the positioning screw (6).

5. A pull-out interlock protector according to claim 4, characterized in that, An annular groove (7) is provided in the fixed end (3). The annular groove (7) is connected to each of the through grooves (5). Each proximity switch SQ is connected in series. The wires between the proximity switches SQ are passed through the annular groove (7). Two wire ports (8) connected to the annular groove (7) are provided on the side surface of the fixed groove. The wires are passed into or out of the wire ports (8).

6. A pull-out interlock protector according to claim 4, characterized in that, A gap (9) is provided between the fixed end (3) and the outer end (2). A partition is provided in the gap (9). The partition is used to hang on the pull-off valve. The two sides of the partition are used to abut against the positioning screw (6) and the proximity switch SQ, respectively.

7. A pull-out interlock protector according to claim 6, characterized in that, The intermediate relay module is a self-locking circuit, which includes a first button SB1, an indicator light D1, and a self-locking coil KA. The self-locking coil KA is connected in series with the first button SB1, and the first button SB1 is located at the normally open point of the coil KA. The indicator light D1 is connected in parallel with a plurality of proximity switches SQ connected in series. One end of the parallel connection between the indicator light D1 and the plurality of proximity switches SQ is connected in series with the positive terminal. The other end of the parallel connection between the indicator light D1 and the plurality of proximity switches SQ is connected in series with the first button SB1. The first button SB1 is connected in series with the negative terminal. The first button SB1 is used to activate the closed circuit.

8. A pull-out interlock protector according to claim 7, characterized in that, A second button SB2 is connected in series between the first button SB1 and the positive terminal. The second button SB2 is used to detect whether the PLC system alarms when the closed loop is broken.

9. A pull-out interlock protector according to claim 1, characterized in that, The proximity switch SQ is an intrinsically safe explosion-proof proximity switch.

Images