Key failure and maintenance of vacuum hot pressing furnace

Fault phenomenon

the reason

Method of exclusion

1. The evacuation valve cannot be opened.

(1) The front valve of the mechanical pump is not open

Reference fault 2

(2) Is the compressed air pressure sufficient?

(2) Requirements to reach 0.4MPa ~ 0.6MPa

(3) The electromagnetic reversing valve of the rough valve does not work.

Reference fault 3

(4) The stroke switch on the high vacuum valve is not compressed.

(4) Adjust the position of the travel switch and the upper cover

2, the mechanical pump front valve can not be opened

(1) Pneumatic air source pressure is not enough

(1) Up to 0.4MPa~0.6MPa

(2) Electromagnetic reversing valve problem

Reference fault 3

3, the magnetic control valve does not work

(1) Turn on the electricity without suction action

(1) The coil is damaged, replace the coil to replace the coil solenoid valve

(2) Low working environment temperature

(2) room temperature is higher than 45 ° C

(3) The valve body is blocked

(3) Clean the valve body by manual-automatic inspection, then inject the pump oil

(4) Insufficient air pressure

(4) 0.4MPa~0.6MPa

4, the front valve can not be opened

(1) Insufficient air pressure

(2) Electromagnetic reversing valve work

Reference fault 3

5, high vacuum valve can not be opened

(1) The stroke switch on the rough valve is not pressed

(1) Adjust the position of the travel switch and upper cover

(2) Insufficient air pressure

(2) 0.4MPa~0.6MPa

(3) Electromagnetic reversing valve

(3) Reference fault 3

(4) Insufficient vacuum (not reached vacuum gauge setting - upper limit)

(4) The composite vacuum gauge (when working) is set to not less than 5Pa

(5) The front valve is not open

(5) The front valve is not open

6 Roots pump does not start

(1) Vacuum gauge J2 is not lit

(1) The degree of vacuum does not reach 2000 Pa or less

(2) 24V power supply burned off

(2) Replace the 24V power supply

(3) The air switch is not closed

(3) Check no problem, close no switch

7 molecular pump does not work

(1) insufficient vacuum

(1) When the molecular pump is fully started, the vacuum must be within 10Pa.

8, the inflatable system does not work

(1) The electromagnetic inflation valve does not operate

(1) The coil is broken, the coil is replaced or the solenoid valve is replaced.

9, the fan does not start

(1) The air switch is not closed

(1) Check no problem, close the switch

(2) Motor damage

(2) Repair or replace the motor

10, the heating current is very uneven

(1) The heating voltage is close to the rated value, the current is zero, and the heating is broken.

(1) Connect or replace with molybdenum screws, nuts and molybdenum sheets

(2) The heating belt is connected to the outer wall

(2) partitioned with ceramic parts, padded, cleaned insulation