CN219955073U - Shutdown protection device for overpressure of pipeline of dosing system - Google Patents

Abstract

The utility model relates to the technical field of pipelines, in particular to a shutdown protection device for overpressure of a pipeline of a dosing system, which comprises a dosing pipeline and further comprises: a diaphragm metering pump is arranged on one side of the dosing pipeline, a branch pipe is connected and arranged on one side of the dosing pipeline, an electric contact pressure gauge is arranged on one side of the branch pipe, a safety valve is arranged on one side of the branch pipe, and a PLC is connected and arranged on one side of the safety valve and the electric contact pressure gauge. The electric contact pressure gauge is added on the basis of retaining the safety valve, so that the process is not increased too much. Is simple and feasible. The added electric contact pressure gauge can monitor the running state of the system through the PLC, so that the investment of inspection personnel is reduced. When the system triggers the shutdown protection, the power is cut off in time to protect the system pipeline and equipment at the source. On the setting of the program, the allowance of pipeline pressure fluctuation is reserved, and the machine is stopped to avoid influencing production due to instantaneous pressure fluctuation. The program setting value can also be adjusted according to the actual situation of the site.

Description

Shutdown protection device for overpressure of pipeline of dosing system

Technical Field

The utility model relates to the technical field of pipelines, in particular to a shutdown protection device for overpressure of a pipeline of a dosing system.

Background

With the continuous improvement of the modern science and technology level, the water pump protection control device is widely applied in various industrial fields, such as secondary water supply, municipal sewage disposal systems and the like, and becomes an important component part of the fields. The pipeline overpressure protection means of most mechanical diaphragm metering pumps at present are compared with the single pressure relief means of a safety valve, so that the pipeline safety valve is a branch of a valve family which is special, and the special is that the pipeline overpressure protection means is different from other valves and only plays a role in opening and closing, and more importantly plays a role in protecting equipment. Along with the rapid development of economic construction in China, more and more equipment project projects with pressure control are performed. In view of the pressure relief requirement of the equipment, the safety valve plays a vital role in the process of protecting the equipment. By 2013, various safety valve manufacturers and traders have exceeded 700, and daily trade inquiry reaches more than 200, so that the safety valve supply and demand market is obviously warmed. Through the first quarter data preliminary analysis, the safety valve demand is twenty percent higher. Safety valves are important safety accessories on boilers, pressure vessels, and other pressurized equipment. The safety valve (also called as relief valve) is automatically opened and closed according to the working pressure (working temperature) of the pressure system, and is generally installed on equipment or pipelines of a closed system to protect the safety of the system. When the pressure or temperature in the equipment or the pipeline exceeds the set pressure of the safety valve, the pressure relief or the temperature reduction is automatically opened, the medium pressure (temperature) in the equipment and the pipeline is ensured to be under the set pressure (temperature), the equipment and the pipeline are protected from working normally, accidents are prevented, and the loss is reduced. Safety valves are mainly widely used: steam boilers, liquefied petroleum gas tank trucks or liquefied petroleum gas rail tank trucks, oil recovery wells, high pressure bypasses of steam power generation equipment, pressure pipelines, pressure vessels, and the like. The safety valve is generally divided into a spring type safety valve and a lever type safety valve according to structural forms, wherein the spring type safety valve is most commonly used; the device is divided into a thread safety valve and a flange safety valve according to a connecting mode. But the system is safe to use singly as a main protection means, the mechanical reliability requirement of the safety valve is high, and the safety valve plays a role in safety protection in the system. When the pressure of the system exceeds a specified value, the safety valve is opened, and part of the medicament in the system is discharged into the return pipeline, so that the pressure of the system does not exceed an allowable value, and the system is ensured not to be in accident due to the overhigh pressure. Common faults of the safety valve are that the valve clack does not return to the seat after being discharged: this is mainly caused by the spring bending the valve stem, the valve clack being improperly installed or stuck. Should be reassembled. Leakage: leakage between the valve flap and the sealing surface of the valve seat occurs beyond the permissible extent under normal operating pressures of the device. The reasons for this are: dirt is arranged between the valve clack and the sealing surface of the valve seat. The valve can be opened for several times by using a lifting spanner to flush dirt; the sealing surface is damaged. Repairing by adopting a grinding or turning grinding method according to the damage degree; the valve rod is bent, inclined or the lever is inclined with the fulcrum, so that the valve core and the valve clack are dislocated. Should be reassembled or replaced; the spring elasticity decreases or loses elasticity. Measures such as spring replacement, readjustment of the opening pressure and the like should be taken. Does not open until a prescribed pressure is reached: this is due to the constant pressure inaccuracy. The compression amount of the spring or the position of the heavy hammer should be readjusted; the valve clack is stuck with the valve seat. The safety valve should be subjected to manual deflation or water discharge test at regular intervals; the lever of the lever-type safety valve is caught or the weight is moved. The position of the weight should be readjusted, and the pressure continues to rise after the lever moves freely to exhaust: the safety valve is mainly used because the discharge capacity of the selected safety valve is smaller than the safety discharge capacity of the equipment, and the proper safety valve is selected again; the valve rod is not correct in center line or the spring is rusted, so that the valve clack cannot be opened to the proper height, and the valve rod is reassembled or the spring is replaced; the exhaust pipe is not cut sufficiently, and the exhaust pipe which accords with the safe discharge area is adopted. Valve clack frequency hopping or vibration: mainly due to the spring rate being too high. A spring with proper rigidity is used; the adjusting ring is improperly adjusted, so that the pressure of the seat back is too high. Readjusting the position of the adjusting ring; the discharge conduit has excessive resistance, resulting in excessive discharge backpressure. The discharge conduit resistance should be reduced. Opening below a specified pressure: mainly, the constant pressure is inaccurate; the spring force decreases as the spring ages. The adjusting screw should be screwed or the spring should be replaced appropriately. When the safety valve fails, the whole pipeline system is in a out-of-control state, and the potential safety hazard is large. The utility model adds the electric contact pressure gauge on the pipeline aiming at the protection mechanism of the single mechanical safety valve, and can ensure that the control system can detect the action condition of the safety valve while keeping the safety valve, thereby providing powerful support for on-site operation maintenance and later data analysis.

Summarizing, the overpressure tube protection device of the prior art has the following technical drawbacks: at present, in PAC, PAM and sodium hypochlorite adding systems, the protection of pipeline overpressure basically stays in the use of a safety valve to relieve pressure and protect pipeline safety, and the reliability dependence on machinery is high. A large amount of personnel are required to be invested for inspection; for the purposes of: in a mechanical diaphragm metering pump dosing system, a common overpressure protection is that a safety valve is arranged, when a pipeline exceeds a set pressure, the safety valve is opened to avoid pipe explosion caused by overlarge pipeline pressure, but a pressure source is generated, the metering pump does not stop running, the metering pump belongs to passive protection, and a safety production accident can occur once the safety valve fails; in the existing dosing system, the pressurizing pipeline exceeds the set pressure, the metering pump is not stopped, and the whole system still runs at idle running, so that energy conservation and environmental protection are not facilitated.

Disclosure of Invention

The utility model aims to provide a shutdown protection device for overpressure of a pipeline of a dosing system, so as to solve the problems in the background technology.

The technical scheme of the utility model is as follows: the utility model provides a shutdown protection device of dosing system pipeline superpressure, includes the dosing pipeline, still includes:

a diaphragm metering pump is arranged on one side of the dosing pipeline, a branch pipe is connected and arranged on one side of the dosing pipeline, an electric contact pressure gauge is arranged on one side of the branch pipe, a safety valve is arranged on one side of the branch pipe, and a PLC is connected and arranged on one side of the safety valve and the electric contact pressure gauge.

According to a further technical scheme, one side of the PLC is connected with a wire cable, and the wire cable is mutually communicated with the safety valve and the electric contact pressure gauge.

According to the further technical scheme, an electric ball valve is arranged on one side of the dosing pipeline in a communicated mode, a backwashing water pipe is arranged on one side of the electric ball valve in a communicated mode, and a backwashing water absorber is arranged on one side of the backwashing water pipe in a communicated mode.

According to the further technical scheme, one side of the PLC and one side of the electric contact pressure gauge are further connected and provided with a control panel, and the surface of the control panel is provided with a fault buzzer.

According to a further technical scheme, a control panel, a buzzer, a diaphragm metering pump, an electric contact pressure gauge and a safety valve are powered in a unified and concentrated mode.

According to a further technical scheme, the transfer joint of the dosing pipeline is kept sealed.

Compared with the prior art, the utility model provides the shutdown protection device for the overpressure of the pipeline of the dosing system by improving, and has the following improvement and advantages:

the electric contact pressure gauge is added on the basis of retaining the safety valve, so that the process is not increased too much. Is simple and feasible. The added electric contact pressure gauge can monitor the running state of the system through the PLC, so that the investment of inspection personnel is reduced. When the system triggers the shutdown protection, the power is cut off in time to protect the system pipeline and equipment at the source. On the setting of the program, the allowance of pipeline pressure fluctuation is reserved, and the machine is stopped to avoid influencing production due to instantaneous pressure fluctuation. The program set value can be adjusted according to the actual condition of the site, and the method can flexibly adapt to the requirements of various working conditions. The whole cost of this patent is lower also does not have great implementation degree of difficulty and can promote on a large scale.

Drawings

The utility model is further explained below with reference to the drawings and examples:

FIG. 1 is a schematic perspective view of the present utility model;

FIG. 2 is a schematic perspective view of the present utility model;

FIG. 3 is a schematic perspective view of the present utility model;

fig. 4 is a flow chart of the working principle of the utility model.

Reference numerals illustrate:

1. a dosing pipeline; 2. a diaphragm metering pump; 3. a branch pipe; 4. an electrical contact pressure gauge; 5. a safety valve; 6. a PLC; 7. a wire cable; 9. an electric ball valve; 10. and back flushing the water pipe.

Detailed Description

The following detailed description of the present utility model clearly and fully describes the technical solutions of the embodiments of the present utility model, and it is apparent that the described embodiments are only some embodiments of the present utility model, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

In the description of the present utility model, it should be noted that, directions or positional relationships indicated by terms such as "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., are based on directions or positional relationships shown in the drawings, are merely for convenience of description and simplification of description, and do not indicate or imply that the apparatus or element to be referred to must have a specific direction, be constructed and operated in the specific direction, and thus should not be construed as limiting the present utility model; the terms "first," "second," "third," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance, and furthermore, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "coupled," and the like are to be construed broadly, and may be fixedly coupled, detachably coupled, or integrally coupled, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present utility model will be understood in specific cases by those of ordinary skill in the art.

Embodiment one:

the utility model provides a shutdown protection device for overpressure of a pipeline of a dosing system by improving the shutdown protection device, which has the technical scheme that:

as shown in fig. 1-4, a shutdown protection device for overpressure of a dosing system pipeline comprises a dosing pipeline 1 and further comprises:

a diaphragm metering pump 2 is arranged on one side of the dosing pipeline 1, a branch pipe 3 is connected on one side of the dosing pipeline 1, an electric contact pressure gauge 4 is arranged on one side of the branch pipe 3, a safety valve 5 is arranged on one side of the branch pipe 3, and a PLC6 is connected on one side of the safety valve 5 and one side of the electric contact pressure gauge 4.

In this embodiment, the mechanical safety valve 5 is installed in a position where the safety valve 5 opens when the system pressure exceeds a predetermined value, and a part of the chemical in the system is discharged into the return line. The device is newly added with the electric contact pressure gauge 4 in the general process, so that the PLC6 control system can monitor the action state of the safety valve 5;

a shutdown protection device for overpressure of a pipeline of a dosing system is characterized in that one side of a PLC6 is connected with a wire cable 7, and the wire cable 7 is communicated with a safety valve 5 and an electric contact pressure gauge 4.

An electric ball valve 9 is arranged on one side of a dosing pipeline 1 in a communicated mode, a back flushing water pipe 10 is arranged on one side of the electric ball valve 9 in a communicated mode, and a back flushing water absorber is arranged on one side of the back flushing water pipe 10 in a communicated mode.

In the embodiment, the electric valve is used for connecting back flushing water to the tail end of the pipeline, and when the system triggers shutdown protection, the electric ball valve 9 is used for opening the back flushing water to flush the two ends of the pipeline; the electric ball valve 9 is opened to discharge sundries blocking the pipeline out of the pipeline when back flushing is performed. Electric contact manometer 4 selection main points: the pressure selection of the electric contact pressure gauge 4 meets the following formula requirement:

p table = 3/2 x P high

Wherein, the P meter is the maximum pressure of the electric contact pressure meter 4; p is the operating pressure of the relief valve 5.

The electric contact pressure gauge 4 should be installed in the front end of relief valve 5, and there is magnetic material in electric contact pressure gauge 4 contact department generally, should be done vibration-proof measure, avoid electric contact pressure gauge 4 to appear the scintillation when critical contact (1 SB) pressure.

A shutdown protection device for overpressure of a pipeline of a dosing system is characterized in that one side of a PLC6 and one side of an electric contact pressure gauge 4 are also connected and provided with a control panel, and the surface of the control panel is provided with a fault buzzer.

The utility model provides a shut down protection device of dosing system pipeline superpressure, control panel, buzzer, diaphragm metering pump 2, electric contact manometer 4 and relief valve 5 adopt unified concentrated power supply.

An overpressure stop protection device for a dosing system pipeline keeps sealing a switching part of the dosing pipeline 1.

Working principle:

1. the working principle and the flow of the device are as follows:

and 1, normal operation of the dosing system or normal operation after recovery from failure.

And 2, the pressure of the dosing pipeline 1 exceeds the preset value of the safety valve 5.

And 3, the relief valve 5 starts to act to relieve pressure.

And 4, setting the action pressure of the electric contact pressure gauge 4 at the front end of the safety valve 5 to be consistent with the set pressure value of the safety valve 5, and transmitting the action signal back to the PLC6 by the electric contact pressure gauge 4 when the safety valve 5 acts.

Step 5. The plc6 converts the return electrical signal into a digital signal for input to the in-process counter.

Step 6.Plc6 converts the return electrical signal to a digital signal for input into the in-process timer.

And 7, the counter in the PLC6 program counts up 5 times, and the shutdown protection is triggered (the times can be adjusted according to the running condition of the on-site dosing system, for example, the dosing system has frequent fluctuation and can be properly adjusted to avoid unnecessary shutdown from affecting production).

And 8, starting to count time to reach 10min when the electric contact pressure gauge 4 acts, triggering shutdown protection (adding a timer function to prevent the drug adding system safety valve 5 from acting for a long time and enabling the drug adding system not to be protected).

And 9, when the dosing system triggers stopping protection, a pipeline back flushing program is started to flush the rear end of the mechanical metering pump, and back flushing water is flushed from the tail end of the pipeline to the front end.

And 10, when the shutdown protection is triggered, a fault lamp on the panel of the control cabinet is turned on, and a fault buzzer is sounded.

And 11, sending a fault reset signal to the PLC after the pipeline back flushing program is finished, and recovering the operation of the metering pump, recovering the fault lamp of the panel of the control cabinet and recovering the action of the buzzer of the panel of the control cabinet.

2. The alternative scheme of the device is as follows:

1. the electric contact pressure gauge 4 can be a pressure transmitter.

2. The electrically operated ball valve 9 may be electrically operated valve such as electrically operated gate valve, electrically operated butterfly valve, solenoid valve.

3. An electrical contact pressure gauge 4 may be mounted in place between the outlet of the mechanical metering pump and the safety valve 5.

4. The in-process counter and timer are not limited to two.

5. The condition of triggering shutdown protection in the program is not only limited to pipeline pressure, but also can be the temperature of a motor of a mechanical metering pump, and the rated current of the motor of the mechanical metering pump.

Finally, it should be noted that: the foregoing description is only illustrative of the preferred embodiments of the present utility model, and although the present utility model has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that modifications may be made to the embodiments described, or equivalents may be substituted for elements thereof, and any modifications, equivalents, improvements or changes may be made without departing from the spirit and principles of the present utility model.

Claims (6)

1. The shutdown protection device for the overpressure of the dosing system pipeline comprises a dosing pipeline (1) and is characterized by further comprising:

the automatic dosing device is characterized in that a diaphragm metering pump (2) is arranged on one side of the dosing pipeline (1), a branch pipe (3) is connected and arranged on one side of the dosing pipeline (1), an electric contact pressure gauge (4) is arranged on one side of the branch pipe (3), a safety valve (5) is arranged on one side of the branch pipe (3), and a PLC (6) is connected and arranged on one side of the safety valve (5) and one side of the electric contact pressure gauge (4).

2. The device for protecting a dosing system conduit from excessive pressure in a machine as claimed in claim 1, wherein: one side of the PLC (6) is connected with a wire cable (7), and the wire cable (7) is communicated with the safety valve (5) and the electric contact pressure gauge (4).

3. The device for protecting a dosing system conduit from excessive pressure in a machine as claimed in claim 1, wherein: an electric ball valve (9) is arranged on one side of the dosing pipeline (1), a back flushing water pipe (10) is arranged on one side of the electric ball valve (9), and a back flushing water absorber is arranged on one side of the back flushing water pipe (10).

4. The device for protecting a dosing system conduit from excessive pressure in a machine as claimed in claim 1, wherein: one side of the PLC (6) and one side of the electric contact pressure gauge (4) are also connected and provided with a control panel, and the surface of the control panel is provided with a fault buzzer.

5. The device for protecting against excessive pressure in a dosing system conduit according to claim 4, wherein: the control panel, the buzzer, the diaphragm metering pump (2), the electric contact pressure gauge (4) and the safety valve (5) adopt unified and centralized power supply.

6. The device for protecting a dosing system conduit from excessive pressure in a machine as claimed in claim 1, wherein: the switching part of the dosing pipeline (1) is kept sealed.