COMMON FAULT ANALYSIS OF POLYUREA SPRAYING MACHINE AND POLYURETHANE SPRAYING EQUIPMENT

1. Feed pump failure

1. The lift pump does not work

The oil cup is too tight to lock the lifting shaft

The crystals on the lifting shaft jam the lifting pump, making the lifting pump unable to work

The rubber of the reversing rubber cover falls off, and the "O" seal is not tightly sealed, making the lifting pump unable to work

The material-lifting pump was inserted into the raw material barrel incorrectly, causing foaming in the pump

The black material is stuck in the pump and cannot work

Insufficient air pressure or no air source

The outlet filter of the feed pump is blocked

The friction resistance of the air motor piston is too large

The gun has no way out

The lower return spring in the cylinder has insufficient elasticity

2. Leakage of the lift pump

Due to long-term use, the "O" ring and "V" ring are worn

(Reversing rubber cover) wear

Air leakage at the thread of the reversing assembly

Reversing assembly falls off

3. Leakage of the lifting pump

Generally refers to the material leakage at the lifting shaft, tighten the oil cup to increase the pressure on the lifting shaft sealing ring

Leakage at other threads

4. The lift pump beats violently

No raw material in raw material barrel

The bottom of the pump is blocked

Raw material viscosity is too thick or too thin

Lifting bowl falls off

2. Booster pump failure

1. Booster pump leakage

Insufficient strength of the oil cup to press the seals leads to leakage

Long-term use of seal wear

2. There are black crystals on the shaft

The oil cup is not tightly sealed, and the booster pump shaft does not stop at the bottom dead center pump shaft. It stays for a long time after there is black material on it

Although the oil cup was tightened, the contaminated lubricant was not replaced

3. The pressure of the two raw materials is inconsistent than 2Mpa

1. The cause of the gun

Different sizes of holes on both sides of the tip

Gun body black material filter is partially blocked

The friction attachment is slightly blocked

The material channel before and after the raw material valve is not completely blocked

The friction attached discharge hole and the holes on both sides of the gun head are not aligned

There is residual material in the mixing chamber of the gun head

One of the raw materials is seriously leaking at the friction attachment

2. Reasons for raw materials

One of the raw materials is too thick

White material temperature is too high

3. Material pipe and heating

The material flow is not smooth due to incomplete blockage in the material pipe

The material pipe is folded into dead bends in many places, which makes the flow of raw materials not smooth

The heater is set too low for the raw material temperature

Raw material pressure gauge malfunction

One of the heaters failed

The heater is not completely blocked due to foreign matter

Material pipe and equipment do not match

4. Reasons for booster pump

Severe material leakage at the booster pump oil cup

The bottom of the booster pump is not tightly sealed

The lower valve body of the booster pump is not tightly sealed

The bowl of the booster pump is worn or the bowl holder is broken

The thread of the lower valve body of the booster pump is loose or the lower valve body falls off

Loose nut on top of booster pump shaft

Damaged "O" ring in the bottom of the booster pump

5. Reasons for lifting pump

The bottom of the lift pump is not completely blocked

The filter at the outlet of the lifting pump is not completely blocked

The lift pump does not work

Serious internal leakage of the lift pump

3. Uneven mixing of the two raw materials

1. Booster pump air source pressure

The triplet pressure reducing valve adjusts the air source pressure to be too low

The discharge pressure of the air compressor cannot meet the requirements of the foaming equipment

The air pipe from the air compressor to the foaming equipment is too thin and too long

Excessive moisture in compressed air hinders air flow

2. Material temperature

The heating temperature of the equipment is not enough for the raw materials

The initial temperature of the raw material is too low and exceeds the scope of equipment

4. The host does not work

1. Electrical reasons

The emergency stop switch is not reset

Proximity switch is damaged

Proximity switch position shift

Two-position five-way solenoid valve out of control

The reset switch is in the reset state

Insurance burnout

2. Causes of gas path

The solenoid valve airway is blocked

Freezing of solenoid valve airway

The "O" ring inside the solenoid valve is not tightly closed and the solenoid valve cannot work

The air motor is severely short of oil

The screw at the connection between the piston and the shaft in the cylinder is loose

3. Reasons for booster pump

The oil cup is too tight

Black material crystals on the lifting shaft are stuck

Unpredictable

The black material is dead in the pump

The pole screw is too loose

5. Pipeline failure

1. Pipeline channeling

The raw material in the raw material barrel is emptied

The bottom of the lift pump is blocked

The filter at the outlet of the lifting pump is blocked

The raw material is too thick

Failure of friction check valve

The white material temperature is too high, and a certain proportion of gas space appears in the material path system

The pressure of the raw material on one side is too high

2. The material tube is not heated

Heating wire open circuit, short circuit

Control system failure

Wrongly connect 220V to 380V power supply

3. The main heater of black and white material does not work

Wrong connection of 220V to 380V power supply will burn out the circuit

Circuit out of control

6. Spray gun failure

1. Gun body foaming

Close the two raw material ball valves and directly remove the two screws fixing the black and white material blocks

2. Gun leakage

The seal between the friction attachment and the gun tip is not tight

Friction and wear

Tip wear

Material leakage at the thread of the friction attached jacket

The seal between the friction attachment and the friction attachment is not tight.

3. The gun does not return after pulling the trigger

The "O" ring on the sliding rod close to the sliding rod piston is not tightly sealed

Wrong position of gun tail cap

The rear spring has insufficient elasticity.

Airway is not completely blocked

4. The gun does not work

Insufficient air pressure

Gun air path blocked

The gun piston circlip falls off

There is foam in the tip chamber

Sliding rod piston resistance is too large

The rubbing cover fails to be screwed in place and the gun head is stuck

Wrong position of gun tail cap

Excessive foreign matter in the slide bar channel:

o-ring wear

5. The gun leaks

Check all "O" rings