Dangerous gas leakage monitoring and leakage preventing system for liquefied petroleum gas filling turntable

Abstract

The invention provides a liquefied petroleum gas filling rotary table hazardous gas leakage monitoring and leakage preventing system which comprises a filling device, combustible gas detectors are arranged on the periphery of the filling device, and a stop valve is arranged on a liquid pipe conveying main pipeline of the filling device; the combustible gas detector is connected with the controller, and the controller is connected with the stop valve; the controller is configured to output a linkage control instruction to drive the stop valve to be closed when the combustible gas concentration detected by the combustible gas detector reaches a preset treatment threshold value, and therefore liquefied petroleum gas supply to the filling device is cut off. According to the hazardous gas leakage monitoring and leakage preventing system for the liquefied petroleum gas filling rotary table, the stop valve is arranged on the liquid pipe conveying main pipeline of the filling rotary table and is directly closed in a linkage mode through the controller, liquid supply can be cut off in the abnormal early stage, continuous accumulation of combustible gas is restrained, and the explosion probability and the accident scale are remarkably reduced.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of control system, in particular to a liquefied petroleum gas filling rotary table dangerous gas leakage monitoring and anti-leakage system. BACKGROUND

[0002] On the liquefied petroleum gas (LPG) cylinder filling production line, empty bottles are usually transported to the filling rotary table with multiple stations through the feeding conveyor belt, and then transported to the subsequent process through the discharging conveyor belt after completing the quantitative filling. Due to the characteristics of LPG, such as low explosion point, high density, and easy accumulation at low places, two types of leakage will inevitably occur during the filling process: one is the micro "normal leakage" generated in the connection and switching of valves and other links, which has low concentration and short duration; the other is the "abnormal leakage" caused by hose damage, seal failure, and valve closure failure, which can easily cause personnel injury and equipment damage risk once the concentration rises to the flammable and explosive range. SUMMARY

[0003] Therefore, the present application aims to provide a liquefied petroleum gas filling rotary table dangerous gas leakage monitoring and anti-leakage system to at least solve one problem in the background art.

[0004] To achieve the above-mentioned purpose, the technical solution of the present application is as follows: A liquefied petroleum gas filling rotary table dangerous gas leakage monitoring and anti-leakage control system applied to a system including a filling device, a combustible gas detector arranged around the filling device, a stop valve arranged on the liquid pipe conveying main pipeline of the filling device, and a controller electrically connected with the combustible gas detector and the stop valve, and a liquefied petroleum gas filling rotary table dangerous gas leakage monitoring and anti-leakage control method, which comprises: The combustible gas detector collects the combustible gas concentration in the filling area, and the controller outputs a linkage control instruction to drive the stop valve to close.

[0005] Further, the liquefied petroleum gas filling rotary table dangerous gas leakage monitoring and anti-leakage control method comprises: The combustible gas detector collects the combustible gas concentration in the filling area, and when the combustible gas concentration reaches the alarm condition or the warning condition inside the combustible gas detector, the corresponding signal is output to the controller, the corresponding signal includes a warning signal or an alarm signal, and the controller performs corresponding operations according to the warning signal or the alarm signal, for example, the controller outputs a warning information when receiving the warning signal, and the controller sends an alarm information and / or a specified preset operation when receiving the alarm signal, the preset operation includes closing the stop valve.

[0006] Further, the liquefied petroleum gas filling rotary table dangerous gas leakage monitoring and anti-leakage control method comprises: S1, collecting combustible gas concentration of the filling area by the combustible gas detector and sending the concentration signal to the controller; S2, comparing the concentration with a preset disposal threshold by the controller; S3, outputting linkage control instruction by the controller to drive the stop valve to close when the concentration reaches the disposal threshold, thereby cutting off liquefied petroleum gas supply to the filling device.

[0007] Further, the filling device is a filling carousel provided with multiple independent filling units.

[0008] Further, the combustible gas detector is connected to the controller through a signal line, and the controller is connected to the stop valve through a control line.

[0009] Further, the disposal threshold is set to be greater than or equal to the c%LEL of liquefied petroleum gas, wherein LEL is the lower explosive limit.

[0010] Further, the stop valve includes an automatic stop valve or a manual stop valve.

[0011] Further, the automatic stop valve is a pneumatic stop valve or an electric stop valve, which is installed on the liquid pipe delivery main pipeline to realize on-off control of liquid supply.

[0012] Further, the manual stop valve is provided with an execution structure on the side, so as to be opened and / or closed by manual operation or the execution structure.

[0013] Further, the controller is further configured to set a warning level threshold outside the disposal threshold, and only output a warning signal without driving the stop valve to close when the concentration reaches the warning level threshold.

[0014] Further, the disposal threshold is set to be between a%LEL-b%LEL of liquefied petroleum gas.

[0015] Further, the controller is also connected to a drive electric control unit of a feeding delivery mechanism, and is configured to control the feeding delivery mechanism to stop running while driving the stop valve to close.

[0016] Compared with the prior art, the liquefied petroleum gas filling carousel dangerous gas leakage monitoring and anti-leakage system has the following advantages: (1) The liquefied petroleum gas filling carousel dangerous gas leakage monitoring and anti-leakage system can cut off the liquid supply in the early stage of abnormality, inhibit the accumulation of combustible gas, and significantly reduce the explosion probability and accident scale by configuring a stop valve on the liquid pipe delivery main pipeline of the filling carousel and directly closing the stop valve by the controller. (2) The liquefied petroleum gas filling turntable dangerous gas leakage monitoring and anti-leakage system, through the double-threshold strategy of the first threshold value and the second threshold value, only sends a warning signal for normal trace escape, avoids unnecessary shutdown, immediately triggers an alarm and executes a disposal cascade when the concentration enters a dangerous interval, and the production continuity and safety are considered; (3) The liquefied petroleum gas filling turntable dangerous gas leakage monitoring and anti-leakage system, when reaching the disposal level threshold value, in addition to closing the main pipeline liquid supply, synchronously controls the loading conveyor belt to stop running, reduces newly added steel cylinders entering the dangerous area, and reduces the possibility of sparks generated by metal member collision. BRIEF DESCRIPTION OF DRAWINGS

[0017] The accompanying drawings, which form a part of the present application, are intended to provide further understanding of the present application, and the illustrative embodiments of the present application and their description serve the purpose of explaining the present application. The accompanying drawings in which: Figure 1 A liquefied petroleum gas filling turntable dangerous gas leakage monitoring and anti-leakage detection logic diagram according to an embodiment of the present application; Figure 2 A liquefied petroleum gas filling turntable dangerous gas leakage monitoring and anti-leakage system structure layout diagram according to an embodiment of the present application; Figure 3 A main pipeline and a stop valve diagram according to an embodiment of the present application.

[0018] Explanation of reference signs: 1-filling turntable; 2-control cabinet; 3-flammable gas detector; 4-loading conveyor belt; 5-unloading conveyor belt; 6-stop valve; 7-main pipeline. DETAILED DESCRIPTION

[0019] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0020] In the description of the present application, it needs to be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element indicated must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second" and the like are only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined with "first", "second" and the like can be explicitly or implicitly included one or more. In the description of the present application, unless otherwise specified, the meaning of "a plurality of" is two or more.

[0021] In the description of the present application, it needs to be understood that unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood through specific circumstances.

[0022] The present application will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0023] As Figure 2 shown, the liquefied petroleum gas filling rotary table hazardous gas leakage monitoring and leakage prevention system of the present embodiment comprises: a combustible gas detector 3 arranged around the filling device (preferably a filling rotary table 1), a stop valve 6 arranged on the liquid pipe delivery main pipeline 7 of the filling device, and a controller electrically connected with both and integrated in a safety control cabinet 2. One end of the liquid pipe delivery main pipeline 7 is connected with an external liquid source, and the other end is connected with multiple groups of electronic filling scales through branch filling pipelines, so as to realize the synchronous filling and weighing of multiple cylinders. In actual use, the feeding end and the discharging end of the filling rotary table 1 are respectively provided with a feeding conveyor belt 4 and a discharging conveyor belt 5: the feeding conveyor belt 4 sends the cylinders to be filled into the filling rotary table 1, and after filling is completed, the cylinders are conveyed to subsequent processes (such as electronic leak detection machines, post-filling inspection machines, sealing machines, and cylinder stacking machines) through the discharging conveyor belt 5.

[0024] The combustible gas detector 3 is used to output the combustible gas concentration signal of the filling area, the type is not limited, and existing products such as electrochemical type or infrared type can be selected on site. The installation position is preferably arranged close to the potential leakage source of the filling position and at a proper low position, so as to improve the response ability to LPG accumulation. The controller in the safety control cabinet 2 is connected with the detector 3 at the input end and connected with the shut-off valve 6 at the output end; the controller outputs the linkage control instruction to drive the shut-off valve 6 to close when determining that the concentration reaches the preset disposal threshold, so as to cut off the LPG supply to the filling device, and form a disposal cascade linkage loop. In order to distinguish between normal trace leakage and abnormal leakage, the controller can be optionally provided with a warning level threshold T1 without changing the scope of protection of the claims: only a warning signal is output when the concentration reaches T1, and no interlocking is performed; when the concentration reaches the disposal threshold T2, the disposal action of closing the shut-off valve 6 is performed. The parameter range can be configured on site: the first threshold T1 can be set to 5% LEL-25% LEL (i.e. a% LEL-b% LEL) of liquefied petroleum gas for prompting normal trace leakage; the second threshold T2 is set to be greater than or equal to 50% LEL or greater than c% LEL for determining abnormal leakage and triggering interlocking. For example, T1 can be set to 25% LEL and T2 can be set to 50% LEL in a certain production line.

[0025] In the disposal scene, in order to reduce the risk of new steel cylinders entering the risk area, the controller can also link the loading conveyor belt 4 to stop running in addition to closing the shut-off valve 6 on the main pipe 7, to realize the cooperative disposal of “valve closing-stop loading”; the linkage function can be enabled or disabled according to the on-site demand, and the stop state is maintained before the manual confirmation of hidden danger elimination and reset is completed. In order to enhance the fault safety ability and maintainability of the system, the shut-off valve 6 can be selected as an automatic shut-off valve or a manual shut-off valve: the automatic shut-off valve can be pneumatic or electric type, and the pneumatic normally closed type structure is preferred to keep closed in abnormal working conditions such as gas loss or power failure; the manual shut-off valve can be opened and closed by manual operation, and an execution structure / execution mechanism (such as existing products such as pre-configured and adjusted mechanical arm or mechanical hand) can be arranged on the side of the manual shut-off valve, so as to open and / or close by manual operation or the execution mechanism. In order to ensure the traceability and reliable execution of the disposal action, the controller can record the valve position feedback, and if the position is not reached within a limited time, it is marked as disposal incomplete and prompts manual intervention.

[0026] After the event, the controller records the detection value, the disposal object and the timestamp, the threshold parameter, the valve position feedback, the feeding conveying mechanism state, the reset personnel and the reset time, and provides an export interface for after-tracing and optimization. The system can be configured with an alarm and an emergency stop button connected with the controller, which is pressed at any time to immediately close the stop valve 6, providing manual intervention redundancy protection. The reset process is as follows: after confirming that the leakage point has been eliminated, completing ventilation and inspection of the pipeline / valve, and executing the reset command on the controller interface, the liquid supply to the liquid pipe conveying main pipeline 7 is restored, and the feeding conveying belt 4 is restored to operation as needed.

[0027] To adapt to multi-station and different ventilation conditions, the detector 3 can be arranged in single-point or multi-point: in multi-point arrangement, each detector is connected to the controller and can adopt the strategy of "disposal as soon as any trigger"; if there are ventilation partitions or physical barriers, the threshold parameters can be configured according to the partition and disposed respectively. In single-point arrangement, the detector 3 is preferably close to the confluence area of multiple leakage sources and avoids strong convection direct blowing position to improve detection representativeness and stability. The interface form of the system is not limited to the upper connection, and can use 4-20mA / RS-485 / switching value and other commonly used industrial interfaces and Ethernet / fieldbus to communicate.

[0028] The product of the embodiment can be an existing device: the filling rotary table 1 and the electronic filling scale can use the products of the company or existing products on the market (for example, the LPG filling rotary table of Tianjin Changlong Hongye Gas Equipment Co., Ltd. can be purchased); the combustible gas detector 3 can use existing products, such as GTY-PD21 point type gas detector; the controller is a conventional industrial control device in the art, and the specific model and brand are not limited.

[0029] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A hazardous gas leakage monitoring and prevention system for a liquefied petroleum gas filling rotary table, characterized in that: The method for monitoring and preventing hazardous gas leaks from a liquefied petroleum gas (LPG) filling rotary table, applicable to a system including a filling device, a combustible gas detector located around the filling device, a shut-off valve located on the main liquid delivery pipeline of the filling device, and a controller electrically connected to the combustible gas detector and the shut-off valve, includes: The combustible gas concentration in the filling area is collected by the combustible gas detector, and the controller outputs a linkage control command to drive the shut-off valve to close.

2. The liquefied petroleum gas filling rotary table hazardous gas leakage monitoring and prevention system according to claim 1, characterized in that, The filling device is a filling turntable with multiple independent filling units.

3. The liquefied petroleum gas filling rotary table hazardous gas leakage monitoring and prevention system according to claim 1, characterized in that, The combustible gas detector is connected to the controller via a signal line, and the controller is connected to the shut-off valve via a control line.

4. The liquefied petroleum gas filling rotary table hazardous gas leakage monitoring and prevention system according to claim 1, characterized in that, The shut-off valve includes an automatic shut-off valve or a manual shut-off valve.

5. A hazardous gas leakage monitoring and prevention system for a liquefied petroleum gas filling rotary table according to claim 4, characterized in that, The automatic shut-off valve is a pneumatic shut-off valve or an electric shut-off valve, installed on the main liquid delivery pipeline to achieve on / off control of the liquid supply.

6. The liquefied petroleum gas filling rotary table hazardous gas leakage monitoring and prevention system according to claim 4, characterized in that, An actuator is provided on the side of the manual shut-off valve so that the manual shut-off valve can be opened and / or closed manually or by the actuator.

7. The liquefied petroleum gas filling rotary table hazardous gas leakage monitoring and prevention system according to claim 1, characterized in that, The controller is further configured to set an alert level threshold outside the treatment threshold, and to output an alert signal without driving the shut-off valve to close when the concentration reaches the alert level threshold.

8. The liquefied petroleum gas filling rotary table hazardous gas leakage monitoring and prevention system according to claim 7, characterized in that, The alert level threshold is set to be between a%LEL and b%LEL for liquefied petroleum gas.

9. A hazardous gas leakage monitoring and prevention system for a liquefied petroleum gas filling rotary table according to claim 3, characterized in that, The controller is also connected to the drive control unit of the feeding conveyor and is configured to control the feeding conveyor to stop operating while driving the shut-off valve to close.

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