Analysis of compressor common failure and explosion mechanism

Update:14-03-2020
Summary:

Common faults during compressor use 1) The compressor t […]

Common faults during compressor use

1) The compressor terminal is connected to the wrong line

2) The compressor terminal cover is removed abnormally

3) The compressor exhaust side is blocked and running with air

4) The air conditioning system contains impurities, moisture, etc.

5) Compressor insulation withstand voltage

6) Refrigerant leakage of air conditioning system

7) Too much refrigerant is sealed in the air-conditioning system

8) Compressor startup failure

 
Compressor terminals are connected incorrectly

The lead wires of the compressor terminals must be connected according to the manufacturer's wiring regulations, and the terminal covers and terminal gaskets provided by the manufacturer must be used. Resistance: RC <SC <RS.

C: common terminal, connected to the neutral wire; R: running terminal, connected to the live wire; S: starting terminal, connected to the capacitor;

Compressor air operation:

Dangerous! Refrigerant oil mixed with air, high temperature and high pressure burned violently, the internal pressure of the compressor surged, the casing burst, and an explosion accident occurred.

 
Mechanism of explosion accident:

1) The compressor is overheated and the refrigerating machine oil is overheated and vaporized;

2) The temperature and pressure of the oil-vapor mixture inside the compressor continue to increase, and under a certain pressure and temperature conditions, the ignition point of the refrigerator oil is reached.

3) The oil-gas mixture is on fire! Temperature and pressure rise sharply!

4) The pressure exceeds the compressive strength of the shell (160 ~ 200kg / cm * 2), and the shell bursts!

 
Common causes of poor starting of compressors:

1) The wiring voltage drop is large, causing the compressor input terminal voltage to be too low and the motor starting torque to be insufficient

2) High and low pressures are not completely balanced, resulting in excessive load torque at startup

3) Compressor starts and stops frequently, internal overheating, and IOL action when restarted

 
Other causes of poor starting:

4) Compressor stuck cylinder: Foreign matter enters the cylinder and causes stall

5) Compressor motor burnout: short circuit between turns of the motor windings; overall motor winding burnout.

 
Moisture in air conditioning system exceeds standard:

1) Water freezes in the circulation system and forms ice plugs.

2) The frozen oil is cracked and delaminated.

3) A large amount of electroplated copper is formed on the pump body castings. Casting is rusty.

 
Hazard of solid impurities in air conditioning system:

1) The moving parts of the compressor are stuck, causing stalls;

2) Metal impurities cause poor insulation withstand voltage and even burn the compressor terminals.

 
Refrigerant leakage of air-conditioning system, main adverse consequences:

1) The air conditioning system cannot operate normally, and the cooling (heating) effect is poor;

2) The compressor exhaust temperature rises abnormally. Oil charring.

3) The motor enameled wire and insulation groove paper are deteriorated.

4) The moving parts of the compressor have poor lubrication and are prone to sintering and abrasion.