Description
Double Eccentric Butterfly Valve
Nominal size: 3â€~*0â€
Pressure rating: Class**0LB~**0LB
Design standard: API **9, MSS.SP**8
End to end: ASME B*6.*0, API**9, MSS.SP**8
Connection type: Flange ends
Materials: WCB, CF8, CF8C, CF8M, CF3, CF3M
Operation Style: Lever, Worm gear, Pneumatic, Electric Actuator,
Hydrodynamic
Test standard: API **8
1. Scope
This manual covers motor , manually
or pneumatic operated ball valves of different types having nominal
size DN*5mm~**0mm(1/2â€~*0â€) 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 + RPTFEÂ Â Â Â Â Â Â Â Â
≤**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
Â
**-
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
 |
Trouble of electric actuator and
pneumatic actuator |
Refer to Electric Valve
Actuator Instruction Manualand Pneumatic Valve Actuator
Instruction Manual |