阅读说明：本技术 一种冷库液氨供液罐非接触式检测装置及控制方法 (Non-contact detection device for liquid ammonia liquid feed tank of refrigeration house and control method ) 是由 李海燕 孙天然 王栅栅 李成献 于 2020-04-17 设计创作，主要内容包括：本发明公开了一种冷库液氨供液罐非接触式检测装置及控制方法,包括供液罐、回气管、上连通管、上非接触式液位计、浮球开关、磁翻板液位计,所述供液罐为金属板制成椭圆形壳体,其一侧上部设置回气管,回气管下面设置上连通管,所述供液罐下部设置下连通管,中部设置浮球开关,所述上连通管和下连通管中间用透明玻璃管连接,透明玻璃管右侧设置磁翻板液位计,透明玻璃管左侧上部设置上非接触液位计,下部设置下非接触液位计,所述供液罐底部中央设置液氨出口,底部周边均布支架,所述供液罐内部盛有液氨,左侧上部设置吸气管,所述吸气管下面设置液氨补充入口,本发明实现了供液罐智能远程控制,同时节约了人工,降低了成本,避免漏氨事故的发生。(The invention discloses a non-contact detection device and a control method for a liquid ammonia supply tank of a refrigeration house, which comprises a liquid supply tank, an air return pipe, an upper communicating pipe, an upper non-contact liquid level meter, a float switch and a magnetic turning plate liquid level meter, wherein the liquid supply tank is an elliptic shell made of a metal plate, the air return pipe is arranged at the upper part of one side of the liquid supply tank, the upper communicating pipe is arranged below the air return pipe, the lower communicating pipe is arranged at the lower part of the liquid supply tank, the float switch is arranged at the middle part of the liquid supply tank, the upper communicating pipe is connected with the lower communicating pipe through a transparent glass pipe, the magnetic turning plate liquid level meter is arranged at the right side of the transparent glass pipe, the upper non-contact liquid level meter is arranged at the upper part of the left side of the transparent glass pipe, the lower non-contact liquid level meter is arranged at the lower part of the liquid supply tank, a liquid ammonia outlet is arranged at the center of the bottom of the liquid supply tank, supports are uniformly distributed at the periphery of the bottom, the liquid ammonia supply tank is filled with liquid ammonia, an air suction pipe is arranged at the upper part of the left side, and a liquid ammonia supplement inlet is arranged below the air suction pipe, the invention realizes the intelligent remote control of the liquid supply tank, saves labor, reduces cost and avoids the occurrence of ammonia leakage accidents.)

1. The utility model provides a freezer liquid ammonia feed tank non-contact detection device which characterized in that: comprises a liquid supply tank (1), an air return pipe (2), an upper communicating pipe (3), an upper non-contact liquid level meter (4), a float switch (5) and a magnetic turning plate liquid level meter (6), wherein the liquid supply tank (1) is an oval shell made of a metal plate, the air return pipe (2) is arranged on the upper portion of one side of the liquid supply tank, the upper communicating pipe (3) is arranged below the air return pipe (2), a lower communicating pipe (8) is arranged on the lower portion of the liquid supply tank (1), the float switch (5) is arranged in the middle of the liquid supply tank, the upper communicating pipe (3) is connected with the lower communicating pipe (8) through a transparent glass pipe, the magnetic turning plate liquid level meter (6) is arranged on the right side of the transparent glass pipe, the upper non-contact liquid level meter (4) is arranged on the upper portion of the left side of the transparent glass pipe, the lower non-contact liquid level meter (7) is arranged on the lower portion, a liquid ammonia outlet (9) is arranged in the center of the bottom of the liquid supply tank (1), a support (10) is uniformly distributed on the periphery of the bottom, and liquid supply tank (1) is internally filled with liquid ammonia (11), an air suction pipe (13) is arranged at the upper part of the left side, and a liquid ammonia supplement inlet (12) is arranged below the air suction pipe (13).

2. The non-contact detection device for the liquid ammonia liquid feed tank of the refrigeration house according to claim 1, characterized in that: the transparent glass tube can also be a stainless steel tube.

3. The non-contact detection device for the liquid ammonia feed tank of the refrigeration house according to claim 1, characterized in that: the transparent glass tube may be a metal tube.

4. The non-contact detection device for the liquid ammonia feed tank of the refrigeration house according to claim 1, characterized in that: the number of the supports (10) is three or more, and the supports are uniformly distributed at the bottom of the liquid supply tank (1).

5. The non-contact detection device for the liquid ammonia feed tank of the refrigeration house according to claim 1, characterized in that: the support (10) is a rectangular truss and is uniformly distributed at the bottom of the liquid supply tank (1).

6. The non-contact detection device for the liquid ammonia feed tank of the refrigeration house according to claim 1, characterized in that: the upper non-contact liquid level meter (4) and the lower non-contact liquid level meter (7) are non-contact liquid level meters with indicator lamps.

7. The non-contact detection device for the liquid ammonia feed tank of the refrigeration house according to claim 1, characterized in that: and an output lead of the floating ball switch (5) is connected with the liquid ammonia pump.

8. The non-contact detection device for the liquid ammonia feed tank of the refrigeration house according to claim 1, characterized in that: the liquid level of the liquid ammonia (11) is not higher than the lower pipe wall of the upper communicating pipe (3) and not lower than the upper pipe wall of the lower communicating pipe (8).

9. The non-contact detection control method for the liquid ammonia liquid feed tank of the refrigeration house is characterized by comprising the following steps of: the upper non-contact liquid level meter (4) monitors the position of liquid ammonia in the communicating pipe in real time, before the compressor is started, the upper non-contact liquid level meter (4) monitors that the position of the liquid ammonia in the communicating pipe does not reach the upper communicating pipe (3), no liquid ammonia exists in the communicating pipe at the upper non-contact liquid level meter (4), an indicator lamp of the upper non-contact liquid level meter (4) is turned off for a long time, the liquid level is normal, a signal of the upper non-contact liquid level meter (4) is transmitted to the PLC, the compressor is started safely, when the upper non-contact liquid level meter (4) monitors that liquid ammonia exists in the communicating pipe, the indicator lamp of the upper non-contact liquid level meter (4) is turned on, a signal of the upper non-contact liquid level meter (4) is transmitted to the PLC, the PLC executes a shutdown program, the power supply of the whole refrigeration system is turned off, an alarm lamp is turned on, and meanwhile, a background server alarm lamp is turned on to give an alarm; have liquid ammonia in lower non-contact level gauge (7) department communicating pipe, then non-contact level gauge (7) pilot lamp is long bright down, the liquid level is normal, non-contact level gauge (7) signal transfer to PLC down, continue the start, compressor safe start, it does not have liquid ammonia in this place communicating pipe to monitor non-contact level gauge (7) down, non-contact level gauge (7) pilot lamp goes out down, non-contact level gauge (7) signal transfer to PLC down, PLC carries out the shut down procedure, close whole refrigerating system power, the alarm lamp is opened, backend server alarm lamp is opened simultaneously, report to the police.

10. The non-contact detection control method for the liquid ammonia feed tank of the refrigeration house according to claim 9, characterized in that: the upper non-contact liquid level meter (4) and the lower non-contact liquid level meter (7) can directly transmit liquid ammonia (11) liquid level signals to the PLC.

Technical Field

The invention relates to the technical field of liquid ammonia of a refrigeration house, in particular to a non-contact detection device for a liquid ammonia liquid feed tank of the refrigeration house and a control method.

Background

The cold storage is a warehouse which utilizes a cooling facility to create proper humidity and temperature conditions, is also called a cold storage and is a place for processing and storing agricultural and livestock products. It can get rid of the influence of climate, prolong the storage and fresh-keeping period of agricultural and livestock products, and regulate the market supply. The cold storage is mainly used for constant temperature storage of food, dairy products, meat, aquatic products, poultry, fruits and vegetables, cold drinks, flowers, tea, medicines and chemical raw materials. From the current situation and the development trend of the refrigeration house, the garlic constant-temperature liquid ammonia refrigeration house is rapidly developed, the proportion of a low-temperature storage is increased to a certain extent, and the garlic constant-temperature liquid ammonia refrigeration house is suitable for being built and used by farmers. Firstly, liquid ammonia absorbs heat of a refrigerating object in an evaporator and is evaporated into ammonia vapor; the ammonia vapor contains liquid ammonia which is not completely gasified, if the liquid ammonia directly returns to a compression cylinder of the compressor, overtaking, namely jacking the cylinder, can be caused due to the liquid ammonia being incapable of being compressed, serious ammonia leakage accidents are generated, and serious losses are caused to lives and properties of people; therefore, mixed ammonia gas which needs to complete a refrigeration task is introduced into the liquid supply tank through the air return pipe, the liquid supply tank is an important accessory device in an ammonia liquid supply system, pure ammonia gas needs to be provided for the compressor, if the compressor sucks ammonia gas containing liquid ammonia from the liquid supply tank, explosion is easy to occur under high temperature and high pressure, a major safety accident is caused, if liquid ammonia is sucked from the liquid supply tank, a machine is damaged lightly, and if the liquid ammonia is crushed, a serious ammonia leakage accident can be caused, for example: in 2013, 8, 31, and 11, the occurrence of liquid ammonia leakage in a cold storage is disclosed in Shanghai Baoshan area. By 2013, 9 and 1, 15 people have been in distress. The direct cause of the accident: when an operator of an ammonia compressor room carries out hot ammonia defrosting operation at an ammonia adjusting station, monitoring video in a production line area of a single refrigerator displays that slight vibration occurs for about 7 times in a field, the duration time of the single vibration is about 1-6 seconds, and a pipe cap at the north end of a return air collecting pipe of the single refrigerator which is carrying out defrosting operation falls off, so that ammonia leakage is caused, and serious accidents are caused. At present, the traditional liquid ammonia is not provided with a high-low level detection and control system, and can not be remotely controlled, once the liquid ammonia in the liquid supply tank exceeds the air outlet pipe, a large amount of liquid ammonia directly enters the working cylinder of the compressor, the compressor and the pipeline can frost at first, the compressor can vibrate, if the power-off shutdown is not found in time, serious ammonia leakage accidents can occur, so that the non-contact detection device and the control method for the liquid ammonia liquid supply tank of the refrigeration house are very important.

Disclosure of Invention

The invention aims at the defects in the prior art, and provides a non-contact detection device and a control method for a liquid ammonia supply tank of a refrigeration house, which can be matched with a remote PLC control system to realize automatic detection of the high and low positions of liquid ammonia and transmit a liquid ammonia position signal to a PLC in real time.

In order to realize the purpose, the invention provides the following technical scheme:

the utility model provides a freezer liquid ammonia feed tank non-contact detection device, includes feed tank, muffler, goes up communicating pipe, goes up non-contact level gauge, float switch, magnetism and turns over the board level gauge, the feed tank makes oval casing for the metal sheet, and its one side upper portion sets up the muffler, sets up communicating pipe below the muffler, the feed tank lower part sets up communicating pipe down, and the middle part sets up the float switch, go up and connect with the clear glass union coupling in the middle of communicating pipe and the lower communicating pipe, clear glass manages the right side and sets up magnetism and turns over the board level gauge, and clear glass manages left side upper portion and sets up non-contact level gauge, and non-contact level gauge is down set up to the lower part, feed tank bottom central authorities set up the liquid ammonia export, the peripheral equipartition support in bottom, feed tank inside contains liquid ammonia, and left side upper portion sets up the breathing pipe, set up liquid ammonia below the breathing pipe and supply the entry.

Preferably, the transparent glass tube can also be a stainless steel tube.

Preferably, the transparent glass tube may be a metal tube.

Preferably, the number of the supports is three or more, and the supports are uniformly distributed at the bottom of the liquid supply tank.

Preferably, the supports are rectangular trusses and are uniformly distributed at the bottom of the liquid supply tank.

Preferably, the upper non-contact liquid level meter and the lower non-contact liquid level meter are non-contact liquid level meters with indicator lamps.

Preferably, an output lead of the float switch is connected with the liquid ammonia pump.

Preferably, the liquid level of the liquid ammonia is not higher than the lower pipe wall of the upper communicating pipe and is not lower than the upper pipe wall of the lower communicating pipe.

Preferably, the non-contact detection control method of the liquid ammonia supply tank of the refrigeration house comprises the steps that the position of liquid ammonia in a communicating pipe is monitored in real time by an upper non-contact liquid level meter, before a compressor is started, the position of the liquid ammonia in the communicating pipe is monitored by the upper non-contact liquid level meter to be not located at the upper communicating pipe, no liquid ammonia exists in the communicating pipe at the upper non-contact liquid level meter, an indicator lamp of the upper non-contact liquid level meter is turned off, the liquid level is normal, signals of the upper non-contact liquid level meter are transmitted to a PLC (programmable logic controller), the compressor is started continuously and is started safely, when the upper non-contact liquid level meter monitors that liquid ammonia exists in the communicating pipe, the indicator lamp of the upper non-contact liquid level meter is turned on, signals of the upper non-contact liquid level meter are transmitted to the PLC, the PLC executes a shutdown program, a power supply of the whole refrigeration system is turned off, an alarm lamp is turned on, and a background server is turned on to give an alarm; there is liquid ammonia in lower non-contact level gauge department communicating pipe, then the non-contact level gauge pilot lamp is long bright down, the liquid level is normal, non-contact level gauge signal transfer gives PLC down, continue the start, compressor safe start, no liquid ammonia in this department communicating pipe is monitored to the non-contact level gauge down, non-contact level gauge pilot lamp goes out down, non-contact level gauge gives PLC with signal transfer down, PLC carries out the shutdown procedure, close whole refrigerating system power, the alarm lamp is opened, backstage server alarm lamp is opened simultaneously, report to the police.

Preferably, the following components: go up non-contact level gauge and lower non-contact level gauge and can directly convey liquid ammonia level signal to PLC.

Compared with the prior art, the invention has the beneficial effects that:

1. the invention is provided with the non-contact liquid level meter, when the magnetic turning plate liquid level meter is inaccurate or fails due to long time or because the magnetic turning plate liquid level meter can only be observed manually at regular time, the power is cut off and electrified manually, but liquid ammonia enters the compression cylinder of the compressor at night or when manual careless management is carried out, and serious safety accidents are caused, so when the control is invalid, the non-contact liquid level meter can automatically detect the liquid level of the liquid ammonia all day long, once the liquid level reaches a danger limit value, the PLC executes a shutdown program to automatically cut off the power supply, and two alarm lamps of a field server and a background server are turned on and automatically give an alarm, thereby effectively avoiding the ammonia leakage safety accidents caused by the liquid ammonia entering the compression cylinder of the compressor and pushing the cylinder, effectively saving the serious loss of lives and properties of people, simultaneously realizing the intelligent automatic monitoring of a liquid supply tank of important equipment without manual all-day inspection supervision, saving labor and reducing cost.

2. The invention is provided with the lower non-contact liquid level meter, when the liquid ammonia pump at the liquid ammonia supplement inlet fails, the compressor still continuously sucks the ammonia gas from the air suction pipe, or the liquid ammonia outlet still continuously sends the liquid ammonia to the evaporator, so that the refrigeration house is not refrigerated, the goods in the whole refrigeration house are damaged and deteriorated, and the serious economic loss is caused, because the lower non-contact liquid level meter is arranged, when the position of the liquid ammonia is lower than the lower non-contact liquid level meter and does not reach the upper pipe wall of the lower communicating pipe, the lower non-contact liquid level meter can transmit signals to the PLC, and simultaneously, the on-site and background servers are turned on, the automatic alarm is realized, the PLC executes the shutdown program, the power supply is cut off, the serious economic loss is avoided, simultaneously, the pure ammonia gas sucked by the compressor is ensured, the liquid ammonia pump has enough liquid ammonia to be supplied to the evaporator, and the equipment damage and the abnormal operation are avoided, the service life of the equipment is prolonged.

3. The invention realizes the automatic detection and control of the high and low positions of the liquid ammonia of the liquid supply tank, lays a foundation for realizing the full intelligent control of a refrigeration house in the future and simultaneously applies a non-contact liquid level meter, does not need to contact the liquid ammonia, ensures the accuracy and reliability of detected data, is very practical and humanized, is widely applied to the existing refrigeration house, generates great economic benefit and social benefit, does not generate ammonia leakage accidents together with the refrigeration house installed at present, and receives the favorable comment of the majority of users.

Drawings

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

FIG. 2 is a diagram of a PLC control method according to the present invention.

In the figure: 1-a feed tank; 2-air return pipe; 3-upper communicating pipe; 4-upper non-contact level gauge; 5-a float switch; 6-magnetic turning plate liquid level meter; 7-lower non-contact level gauge; 8-descending communicating pipe; 9-liquid ammonia outlet; 10-a scaffold; 11-liquid ammonia; 12-a liquid ammonia make-up inlet; 13-suction pipe.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

As shown in figure 1, a non-contact detection device for a liquid ammonia supply tank of a refrigeration house comprises a liquid supply tank 1, an air return pipe 2, an upper communicating pipe 3, an upper non-contact liquid level meter 4, a float switch 5 and a magnetic turning plate liquid level meter 6, wherein the liquid supply tank 1 is an oval shell made of a metal plate, the air return pipe 2 is arranged on the upper portion of one side of the liquid supply tank, the upper communicating pipe 3 is arranged below the air return pipe 2, a lower communicating pipe 8 is arranged on the lower portion of the liquid supply tank 1, the float switch 5 is arranged in the middle of the liquid supply tank, the upper communicating pipe 3 is connected with the lower communicating pipe 8 through a transparent glass pipe, the magnetic turning plate liquid level meter 6 is arranged on the right side of the transparent glass pipe, the upper non-contact liquid level meter 4 is arranged on the upper portion of the left side of the transparent glass pipe, the lower non-contact liquid level meter 7 is arranged on the lower portion of the liquid supply tank 1, a liquid ammonia outlet 9 is arranged in the center of the bottom of the liquid supply tank 1, supports 10 are uniformly distributed on the periphery of the bottom, liquid ammonia 11 is contained in the liquid supply tank 1, an air suction pipe 13 is arranged on the upper portion of the left side, a liquid ammonia replenishment inlet 12 is provided below the suction pipe 13. The transparent glass tube can also be a stainless steel tube. The transparent glass tube may be a metal tube. The number of the supports 10 is three or more, and the supports are uniformly distributed at the bottom of the liquid supply tank 1. The support 10 is a rectangular truss and is uniformly distributed at the bottom of the liquid supply tank 1. The upper non-contact liquid level meter 4 and the lower non-contact liquid level meter 7 are non-contact liquid level meters with indicator lamps. And an output lead of the float switch 5 is connected with the liquid ammonia pump. The liquid level height of the liquid ammonia 11 is not higher than the lower pipe wall of the upper communicating pipe 3 and is not lower than the upper pipe wall of the lower communicating pipe 8, when the upper communicating pipe 3 is connected with the lower communicating pipe 8 by a transparent glass pipe, the magnetic turning plate liquid level meter 6 does not need to be arranged, the liquid level height can be directly observed by manpower, but when the middle part of the upper communicating pipe 3 is connected with the lower communicating pipe 8 by a stainless steel pipe or other metal pipes, the magnetic turning plate liquid level meter 6 needs to be arranged so as to facilitate field observation.

As shown in fig. 2, a non-contact detection control method for a liquid ammonia feed tank of a refrigeration storage includes: the position of liquid ammonia in a communicating pipe is monitored in real time at an upper non-contact liquid level meter 4, before a compressor is started, the upper non-contact liquid level meter 4 monitors that the position of the liquid ammonia in the communicating pipe does not reach an upper communicating pipe 3, no liquid ammonia exists in the communicating pipe at the upper non-contact liquid level meter 4, an indicator lamp of the upper non-contact liquid level meter 4 is turned off for a long time, the liquid level is normal, a signal of the upper non-contact liquid level meter 4 is transmitted to a PLC (programmable logic controller), the compressor is started continuously and is started safely, when the upper non-contact liquid level meter 4 monitors that liquid ammonia exists in the communicating pipe, the indicator lamp of the upper non-contact liquid level meter 4 is turned on, a signal of the upper non-contact liquid level meter 4 is transmitted to the PLC, the PLC executes a shutdown program, a power supply of the whole refrigerating system is turned off, an alarm lamp is turned on, and meanwhile, a background server alarm lamp is turned on to give an alarm; there is liquid ammonia in 7 department's communicating tubes of non-contact level gauge down, then 7 pilot lamps of non-contact level gauge are bright for a long time down, the liquid level is normal, 7 signal transmission of non-contact level gauge are to PLC down, continue the start, compressor safe starting, 7 monitor here communicating tubes of non-contact level gauge do not have liquid ammonia down, 7 pilot lamps of non-contact level gauge extinguish down, 7 signal transmission of non-contact level gauge are to PLC down, PLC carries out the shutdown procedure, close whole refrigerating system power, the alarm lamp is opened, backend server alarm lamp is opened simultaneously, report to the police. The upper non-contact liquid level meter 4 and the lower non-contact liquid level meter 7 can directly transmit liquid ammonia 11 level signals to the PLC.

When the refrigeration system is used, liquid-gas mixed gas obtained after heat absorption and gasification of liquid ammonia in an evaporator enters a liquid supply tank 1 through an air return pipe 2, liquid ammonia is deposited to the bottom layer to form liquid ammonia 11, the position of the liquid ammonia can be observed manually by a magnetic turning plate liquid level meter 6, pure ammonia enters a compressor through an air suction pipe 13 and then enters a condenser after being compressed by the compressor, ammonia in the condenser forms liquid ammonia and then enters an ammonia storage tank, the ammonia storage tank is communicated with a liquid ammonia supplement inlet 12 through a pump, the liquid ammonia 11 is sent to the evaporator through a liquid ammonia pump, the ammonia formed by the evaporator enters the liquid supply tank 1 through the air return pipe 2, and the circulation is carried out, so that refrigeration of a refrigeration house is completed; when liquid ammonia 11 is continuously pumped by a liquid ammonia pump, the liquid level of the liquid ammonia 11 descends, and reaches a certain position, a float switch 5 is opened, a pump connected with a liquid ammonia supplement inlet 12 starts to supplement the liquid ammonia 11 from an ammonia storage tank to a liquid supply tank 1, the liquid level of the liquid ammonia 11 rises along with the liquid ammonia, when the liquid ammonia reaches a certain upper position, the float switch 5 is closed, the pump stops supplementing the liquid ammonia to the liquid supply tank, but the float switch 5 fails in use, at the moment, only a magnetic flap liquid level meter 6 can be observed manually, the problem is found manually in time, the manual machine is stopped, the float switch 5 is replaced, however, the manual machine cannot stare at the liquid in all weather, if the situation occurs at night, the pump does not stop supplementing the liquid ammonia 11 to the liquid supply tank 1, when the liquid ammonia reaches an air suction pipe 13, a large amount of liquid ammonia 11 enters a compression cylinder of the compressor, the common knowledge shows that the liquid state cannot be compressed, so that the high-power compressor can crush the compression cylinder, the invention provides a non-contact detection device and a control method of a liquid ammonia supply tank of a refrigeration house, which can realize unmanned intelligent remote control at extremely low cost without contacting liquid ammonia or performing shutdown transformation on a large amount of existing refrigeration house facilities and can realize unmanned intelligent remote control, wherein an upper non-contact liquid level meter 4 and a lower non-contact liquid level meter 7 are arranged in the device, position signals of liquid ammonia 11 can be transmitted to a PLC controller in real time, when the liquid level of the liquid ammonia 11 is close to an upper communicating pipe 3, the upper non-contact liquid level meter 4 transmits signals to the PLC controller, a field alarm lamp is turned on to give an alarm, and meanwhile, the PLC controller remotely executes a shutdown program to cut off a power supply to cut off the power supply, meanwhile, the alarm lamp of the background server is turned on, the background alarm is carried out, the occurrence of serious ammonia leakage accidents is avoided, field technicians and background technicians are reminded to timely go to the field for treatment, the serious loss of lives and properties of people is avoided, the labor is saved, the labor intensity of the technicians is reduced, and the cost is reduced. The invention is very practical and humanized, is widely applied to the existing refrigeration houses, generates great economic benefit and social benefit, and is valued by local governments and praised by the majority of users of the existing refrigeration houses.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.