Installation and Maintenance of Ball Valve

Ball Valve Installation:

 1. It must be confirmed that the pipes and valves have been cleaned before operation.

 2. The actuator operation of the valve drives the stem to rotate according to the size of the input signal. When the valve rotates 1/4 times (900) in the forward direction, the valve closes. When the reverse rotation is 1/4 turn (900), the valve opens.

 3. When the direction of the actuator indicates that the arrow is parallel to the pipeline, the valve opens; when the arrow is perpendicular to the pipeline, the valve closes.

Ball Valve Maintenance:

 A longer service life and maintenance-free time will depend on several factors: maintaining a harmonious temperature/pressure ratio under normal working conditions, and reasonable corrosion data.

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Note: When the ball valve is closed, the fluid pressure in the valve body still exists.

Before repair, remove line pressure and keep valve in open position

Before maintenance, disconnect the power or gas source

Separate the actuator from the bracket before maintenance

1. Packing locking

 If the filling culvert is slightly leaky, the stem nut must be locked.

 Note: Do not lock, usually lock 1/4 ring to 1 ring, leakage will stop.

 2. Replacement of Seats and Seals

 A. Disassembly

 Leave the valve in a half-open position and flush the dangerous substances that may exist inside and outside the valve.

 Close the ball valve, remove the bolts and nuts of flanges on both sides, and remove the valve completely from the pipeline.

 Disassemble the driving device in sequence – actuator, connecting bracket, anti-loosening washer, stem nut, butterfly spring, Gnan, wear-resistant plate, stem packing.

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

 Confirm that the ball is in the “off” position, which makes it easier to remove it from the body and then remove the seat.

 The stem is pushed down through the hole in the valve body until it is completely removed, and then the O-ring and packing ring are removed.

 Note: Please operate with caution to avoid scratching the stem surface and packing seal of the valve.

2

B. Reassembly

 Clean and inspect the parts inspected. Replacement of seat and cover gaskets and seals with spare parts packages is strongly recommended.

 Assemble in reverse order of disassembly and assembly.

 Cross-lock flange bolts with specified torque.

 Lock nuts with specified torque.

 After installing the actuator, the valve spool is driven to rotate the corresponding input signal by rotating the stem to make the valve open and close.

 If possible, test the sealing pressure and performance of the valve according to the standard after installation of the pipeline.

 


Post time: Jun-13-2019

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