Ball valve maintenance manual

Ball valve Daily maintenance is very importance,With a long service life and maintenance-free period, it will depend on several factors: normal working conditions, maintaining a harmonious temperature/pressure ratio, and reasonable corrosion data.

When the ball valve is closed, there is still a pressurized fluid inside the valve body.

Here is an ouline:

1. Before ball valve's repair

2. Special tools should be used when removing the O-rings of industrial valves.

3. After ball valve cleaning

4. Note

   
   

A. Before ball valve's repair

Release the line pressure and open the valve; disconnect the power or air supply; disconnect the actuator from the bracket,It must be ascertained that the upper and lower pipes of the ball valves have been relieved of pressure before they can be disassembled and disassembled.Care must be taken during the disassembly and reassembly to prevent damage to the sealing surfaces of the parts, especially for non-metallic parts.

B. Special tools should be used when removing the O-rings of industrial valves.

The bolts on the flange must be tightened symmetrically, stepwise and evenly during assembly,The cleaning agent should be compatible with the rubber parts, plastic parts, metal parts and working medium (such as gas) in the ball valve. When the working medium is gas, the metal parts can be cleaned with gasoline. Non-metallic parts are cleaned with pure water or alcohol Non-metallic parts should be taken out of the cleaning agent immediately after cleaning. Do not soak for a long time.

C. After ball valve cleaning:

Ball valve needs to be assembled after the wall cleaning agent is volatilized (can be wiped with silk cloth without dipping agent), but it should not be left for a long time, otherwise it will rust and be polluted by dust.New parts need to be cleaned before assembly Metal debris, fibers, grease (except for the use), dust, other impurities, foreign matter, etc., shall not be allowed to be contaminated, adhered or stay on the surface of the part or enter the inner cavity. If there is micro-leakage at the packing, it shall be Then tighten the stem nut.

D. Note: 

Do not lock too tightly, usually lock 1/4 turn to 1 turn, the leak will stop.

A), disassembly

Put the valve in the half-open position to flush and remove dangerous substances that may exist inside and outside the valve.

Close the ball valve, remove the connecting bolts and nuts on the flanges on both sides, and then completely remove the valve from the line.

Disassemble the drive unit-actuator, connecting bracket, lock washer, stem nut, butterfly shrapnel, Grennan, wear plate and stem packing.

Remove the body cover connecting bolts and nuts, separate the bonnet from the valve body, and remove the bonnet gasket.

Verify that the ball is in the "off" position, which allows it to be easily removed from the valve body and then removed from the seat.

Push the valve stem down from the hole in the valve body until it is completely removed, then remove the O-ring and the stem under the valve.

Note: Be careful to avoid scratching the stem surface and the body packing seal.

B), reassembly

Cleaning and inspection of the removed parts, it is highly recommended to replace the seals such as the seat and bonnet gasket with spare parts.

Assemble in the reverse order of disassembly.

Use the specified torque to cross-lock the flange connection bolts.

Lock the stem nut with the specified torque.

After installing the actuator, input the corresponding signal to rotate the spool through the rotary valve stem to open the valve to the open and closed positions.

If possible, perform a pressure seal test and performance test on the valve in accordance with relevant standards before returning the pipe.