The inert gas shielding gas flow classifier is a closed gas flow classification system developed for the classification requirements of special materials such as flammable, explosive, and easy to oxidize using inert atmosphere gas (nitrogen, argon, carbon dioxide, etc.) circulation protection. The system is upgraded from an ordinary air flow classifier system, which is mainly composed of a closed feeding system, air flow classification system, gas circulation system, and control system. Most of them adopt PLC program control, which reduces human operation and control factors. The control cabinet can be placed in a remote independent control room. Automatic packaging machine is used for packaging and unloading, and monitoring probes are used for on-site observation, which can realize unmanned operation.

In terms of safety, the inert gas shielded gas flow classifier mainly has the following characteristics:

1.   Isolate oxygen and produce fully enclosed. Before the equipment is put into operation, replace the air in the closed loop system with nitrogen. At the same time, the closed filling and unloading system can replace the small amount of air brought in during the filling and unloading process with nitrogen to keep the oxygen content in the system basically stable.

During this process, the oxygen content in the gas stream is continuously monitored with an oxygen content analyzer. When the oxygen content exceeds a certain level, add nitrogen immediately to keep the oxygen content within the safety production standard.

2.  Control the concentration of gas and powder. The feeding system of this equipment is a fully enclosed uniform speed device, which is programmed and controlled by the control cabinet. The fully enclosed system can isolate oxygen and control the concentration of materials in the equipment at a constant speed. The feed speed can be set arbitrarily.

If the materials added to the equipment at a constant speed will accumulate in the equipment, safety will not be guaranteed. Therefore, scientifically calculate the shape of the equipment, such as the bending angle of the pipe and the shape of each part, in order to eliminate the dead angle inside the equipment. At the same time, the powder will not accumulate in the pipeline through the driving and scouring of the high-speed airflow in the equipment.

3.  Discharge static electricity in time to eliminate fire sources. The pulse dust collector adopts a special carbon steel wire filter material, which can eliminate static electricity in time and ensure that the pulse is cleaned thoroughly. The equipment is all metal parts, all of which are grounded to discharge the powder static electricity as much as possible.

4.  Circulating air cooling. Since the entire system is a closed loop system, there are many moving parts in the equipment, and a certain temperature will be generated during high-speed movement. Temperature is very important to the safety of processing. Therefore, installing radiators and coolers on the pipelines of the equipment can effectively reduce potential safety hazards caused by long-term operation or high-temperature environments.

5.  Explosion-proof. Explosion-proof holes are provided in different positions of the entire pipeline to minimize the loss when the system internal pressure and concentration are too high to cause an explosion. The motors and other equipment used in the entire system are explosion-proof motors with good sealing performance, effectively reducing dust accumulation.

6.  Emergency shutdown. The equipment emergency shutdown trigger switch is connected to the oxygen content analyzer. If the oxygen content monitored by the oxygen content analyzer does not reach the set value within a predetermined time, an emergency shutdown is triggered, the equipment stops feeding, the induced draft fan stops, and the classifier delays. The nitrogen supplement system continues to work until it is manually shut down.