Do not touch the air compressor and the gas tank safety high voltage line to prevent spontaneous combustion and explosion
Do not touch the air compressor and the gas tank safety high voltage line to prevent spontaneous combustion and explosion.
Comply with six safety guidelines, completely eliminate safety hazards
1. The gas storage tank is strictly prohibited from overpressure and over temperature. The operator should ensure that the gas storage tank is in normal working condition.
2. It is strictly forbidden to use an open flame around the gas tank or on the container. It is forbidden to use the open flame to inspect the inside of the container. When the gas storage tank is under pressure, no maintenance or impact on the tank and other objects shall be carried out.
3. For oil-lubricated compressors, it must be degreased and dewatered. The oil content of compressed air, water vapor content and solid particle size and concentration grade are in accordance with GB/T3277-91 "General Compressed Air Quality Grade" appendix. After the provisions of A, you can enter the gas storage tank.
4. In view of the contact between oil and air in the air compressor, once the temperature is too high, the self-ignition of the carbon deposit and the ignition mechanism of the oil explosion are likely to occur, and the compressed air entering the gas storage tank is strictly prohibited from exceeding the design temperature of the tank. In order to avoid excessive exhaust gas temperature, the air compressor must check the over-temperature shutdown device on time, regularly check the heat transfer surfaces (filters, separators and coolers) and clean.
5. For oil-lubricated compressors, all pipelines, vessels (gas storage tanks) and fittings between the exhaust port and the compressed air temperature of 80 degrees should be regularly inspected. Any coke should be effectively removed (including the compressor cylinder head). Carbon deposits).
If the unit of the gas storage tank is not implemented in accordance with the above requirements and warnings, it may cause serious consequences of the gas tank failure and explosion. Please remember to use the unit!
The mechanism of spontaneous combustion of carbon deposits and the cause of oil explosion
1
The oil is in contact with the air to cause an oxidation reaction, and the rate of the oxidation reaction increases with temperature, partial pressure of oxygen, and iron or iron oxide particles acting as catalyst. The oxidation reaction increases the viscosity of the oil. If the oil stays in the hot zone for a sufficient period of time, it may form coke in the compressor exhaust system. These deposits continue to oxidize, and there is a necessary condition for spontaneous combustion due to the exothermic phenomenon caused by the oxidation reaction.
2
In fact, the heat generated by the oxidation reaction is cooled and carried away by the air flow above the carbon deposits, and on the other hand by the carbon deposits carried by the carbon deposits. When the heat generated by the oxidation reaction cannot be taken away in time, the temperature of the carbon deposit layer rises, and in special cases, the temperature of spontaneous combustion of the carbon layer is reached, and sufficient heat is generated to weaken or melt the metal in the pressure system. Although no real explosion occurs, such sudden damage to the wall can be mistaken for an explosion.
3
Studies have shown that in order to cause oil to ignite, it is necessary to have a certain thickness of carbon deposits, the ambient temperature should be +150 ° C and a certain limit of heat conduction through the carbon layer (often referred to as dryness). Under these conditions, when the compressed air flowing over the carbon deposit layer is excessively reduced, causing a decrease in the heat dissipation rate, the fire may occur during eating, rest, shifting, or when the compressor is operating at no load, or When the air flow condition changes, and the heat generated by the carbon layer causes the internal temperature to be higher than the auto-ignition temperature, a fire phenomenon may occur.
4
The critical thickness of the dangerous carbon deposit varies with the pressure and temperature of each compressor air, the impurity particles in the deposit, the actual location of the deposit, and the operating conditions of the compressor. Therefore, the safe thickness of the carbon layer will vary from compressor to compressor.
5
Sometimes, the ignition of oil in a pressure system causes an explosion of oil vapor or oil mist, which is rarely the case. This situation must occur that the ratio of air to oil mixture is within the limits of the explosion and is in contact with the source of spontaneous combustion.
6
The range of ratios of air to oil mixing required to cause an explosion is limited. Excessive oxygen or excessive flammable materials can suppress the explosion, which may be the main cause of the rare explosion, but it must always be aware of the danger.
7
There is very little reference to explain the exact cause of the initial oil explosion in the compressor. However, the following explanation is quite possible. When the compressor is unloaded, there is no air flowing through the carbon layer to cause fire. After a period of time, the oxygen in the air is not completely combusted, and the resulting carbon monoxide, together with the oil and oil mist decomposed or oxidized from the carbon deposit, forms a potentially flammable mixture. The flammable mixture and oil mist flow to the cooler portion downstream of the exhaust system where it is mixed with unburned air to produce an explosive mixture. Under these conditions, when the compressor starts the exhaust air again, the air flow suddenly increases, the burnt carbon particles are loosened, and it is sent to an explosive area, and an explosion may occur. It must be noted that even if no explosion occurs, the compressed air will be contaminated by harmful gases generated by incomplete combustion.
8
When the inner wall of the lubricating oil compressor exhaust pipe has a thin oil film, this initial explosion will explode in a more violent explosion. Due to the sufficiently strong shock wave transmitted to the exhaust pipe by the initial explosion, the oil film is peeled off from the pipe wall and a mixture of oil mist and air is formed. If a flammable mixture is produced and the temperature of the shock wave reaches the temperature of self-ignition, a second explosion occurs, which accelerates the shock wave to the explosion speed (ultrasonic wave), at which time the brittle fracture of the pipe wall occurs, which may be compressed from time to time. The air duct of the machine is repeated, causing frequent damage on the inner surface of the pipe. This type of explosion is extremely damaging to the pressure system and is also very dangerous for the person attaching it.
9
If the formation of carbon deposits is minimized in strict accordance with the provisions of this standard, the risk of oil ignition or explosion will be minimized.
Attached:
Gas tank use instructions
1. The unit of use of the gas storage tank should be installed by the unit holding the “Pressure Vessel Installation License”.
2. Before putting into use, you must go through the registration procedures one by one with the safety supervision agency or authorized department according to the requirements of the “Regulations on the Registration of Pressure Vessel Use”.
3. If the ambient temperature of the gas storage tank is lower than zero, the gas storage tank must be installed indoors, and the insulation measures should be taken to ensure the safe use of the gas storage tank within the allowable working temperature range.
4. The technical person in charge of the gas storage unit shall be responsible for the safety management of the pressure vessel. The use unit must establish a complete safety management rules and regulations for pressure vessels, including the implementation of the "Fixed Containment Regulations" and related pressure vessel safety technical specifications, gas tank registration and technical data management, and the development of a complete process and post operating procedures. .
5. The gas tank operator should participate in the professional training and safety education held by the safety supervision agency or authorized department, and obtain the "Special Equipment Operation Personnel Certificate" to carry out the operation.
6. The use of the unit's gas storage tanks shall be in accordance with the “Regulations on Periodic Inspection of Pressure Vessels” and “Regulations on the Administration of Use of Pressure Vessels”, and the pressure vessel inspection unit shall conduct regular inspections and assess the safety status.
7. The repair and technical transformation of the gas storage tank must be carried out in accordance with the provisions of the “Safety Technical Supervision Regulations for Fixed Pressure Vessels”. The use unit shall not carry out repairs and technical transformation of the gas storage tanks without authorization.
8. The safety accessories (safety valves, pressure gauges, etc.) on the gas storage tanks should be subject to a regular inspection system (safety valves should be inspected at least once a year, pressure gauges should be inspected every six months), and the inspection should be performed by a qualified unit or The department is conducting. The operator should always check whether the safety accessories are valid and ensure that the safety accessories work normally. If they fail or the accuracy is not up to the specified requirements, they should be replaced.
9. If the maximum volume flow of the compressor (the actual intake air volume of the gas storage tank) exceeds the safe discharge amount of the gas storage tank, the user should install a pressure release device in the system.
10. The gas storage tank and the air compressor should be kept at a certain distance. The installation distance between the two should not be less than 2 meters. Within 5 meters, the hose should be connected. If the pipe is connected, a buffer elbow should be set.
11. According to the actual use situation, the user performs regular sewage discharge and regular cleaning on the gas storage tank to ensure the air quality inside the tank.
