Description

Fully Welded Ball Valve
Nominal size: 1/2”~*0”
Pressure rating: Class**0LB~***0LB
Design standard: API 6D, ASME B*6.*4
End to end: API 6D, ASME B*6.*0
Connection type: Butt-welding ends
Materials: A**5
Operation Style: Lever, Worm gear, Pneumatic, Electric Actuator, Hydrodynamic
Test standard: API **8, API 6D


1. Scope
This manual covers motor , manually or pneumatic operated ball valves of different types having nominal size DN*5mm~**0mm(1/2”~*0”) and class PN1.6MPa~*0MPa(ANSI CLASS**0~**0). The valve ends can be threaded, flanged, butt-welded or socket-welded.
2. Application
2.1 Ball valves are used to open or close fluid in pipeline or facilities.
2.2 The nature of applicable fluid depends on valve material.
2.2.1 Carbon steel valves apply to non-corrosive fluid, such as water, vapor or oil, etc.
2.2.2 Stainless steel valves apply to corrosive fluid.
2.3 Temperature range depends on seat material:
PTFE                ≤**0℃
PTFE + RPTFE          ≤**0℃
PPL                 ≤**0℃
3. Structure
3.1 Valve structure is shown in Fig.1
3.2 Gasket and packing are PTFE or GRAPHITE. They are used to secure sealing.
4. Operation
4.1 Manual valves, motor valves or pneumatic valves use hand-wheel, electric or pneumatic actuator to open or close the valve by ball rotating *0°
4.2 There’s a flute on the top of stem of manually operated ball valves. When the direction of flute and spanner complies with the direction of fluid the valve is open. When they are vertical the valve is closed.
4.3 The open/close of motor or pneumatic valves is indicated by instructive mark.
5. Storage, maintenance, installation and service
5.1 The valve should be stored in dry room with good ventilation. Valve ends should be covered.
5.2 For valves stored for a long period of time, regular checkup is required to ensure that the valves are in good conditions. Foreign particles should be removed and special care should be taken to keep the valves seat sealing face.
5.3 Check the conformance of valve identification to the service requirements prior to installation.
5.4 Check the cleanness of the valve cavity and sealing surface and wipe off any dirt with white cloth prior to installation.
5.5 Before installation, the tightness of packing should be checked to ensure that sealing is secured without affecting the movement of stem.
5.6 The valve shall be in full open position when conducting system or pipeline pressure test after the valve installation.
5.7 Ball valve shall be in full open or full close position whole in service. Partial opening for controlling the flow is not allowed.
5.8 Manually operated valve should be operated by using the hand-wheel. Use of levers or other tools is not allowed.
5.9 Valve in service should be examined at prescribed intervals to see whether the wear of sealing surface or stem occurs and the gasket or packing fails. Repair or replacement shall be carried out timely if necessary.
5.*0 Electric Valve Actuator Instruction Manualand Pneumatic Valve Actuator Instruction Manual should be referred with regard to the storage, maintenance, installation and service for motor-operated valve.
6. Possible troubles, cause and solution
 
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Possible troubles, cause and solution

Possible trouble	Cause	Solution
Leakage through packing	1.Packing not sufficient pressed 2. Packing failure	1.Tighten the nut to press packing evenly 2.Replace packing
Leakage from sealing surface	1. Some contamination adhered to the sealing surface 2. Damage of the sealing surface	1.Clean up the contamination 2.Repair or change
Leakage from middle flange	1.The body and the bonnet are not joint tightly 2.The sealing surface of middle flange spoiled 3.Gasket is broken or useless	1.Fix bolts and nuts averagely 2.Repair the sealing surface 3.Change the middle flange gasket
The hand lever cannot turn smoothly or cannot open and close the valve	1.Packing is pressed too tight 2.Packing gland is deflected	1.Loosen the nuts properly 2.Adjust packing gland Â
Trouble of electric actuator and pneumatic actuator	Refer to Electric Valve Actuator Instruction Manualand Pneumatic Valve Actuator Instruction Manual