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BZ9 Series Ball Valves
IOM-BZ9
WELDING ENDS
Welding of valves shall be performed by a qualified
person according to the ASME Boiler Construction code
Section IX. Sweat End valves must be partially disassem-
bled to prevent heat damage during welding of the soft
plastic seats and seals in the valve. Prior to disassembly,
the valve may be temporarily fitted in line, and the ends
tack-welded to the piping for alignment purposes.
1. With the valve in the OPEN position, remove Body
Bolts (#9) and Body Bolt Nuts (#10).
2. Separate the End Connections (#2) from the Body
(#1) and carefully remove the Seats (#5), Body
Seals (#13) and Ball (#3) to avoid damaging them.
3. With the soft components and Ball (#3) removed
from the Body (#1), loosely reassemble the End
Connections (#2) to the valve Body (#1).
4. Tack weld the End connections (#2) to the pipeline,
then remove the valve Body (#1).
5. Complete the welding, being careful to avoid weld
splatter on the exposed end faces.
6. When cooled, clean faces of the ends before reas-
sembling the valve.
(See Reassembly Procedure)
OPERATION
SVF valves provide tight shut off when used under normal
conditions and in accordance with SVF’s published
pressure/temperature chart. If these valves are used
in a partially open (throttled) position seat life may be
reduced.
SVF valves have ¼ turn operation closing in a clockwise
direction. It is possible to see when the valve is open
or closed by the position of the wrench handle. When
the wrench is in line with the pipeline, the valve is open.
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the flow path.
Any media which might solidify, crystallize or polymerize
should not be allowed to stand in the ball valve cavities
unless regular maintenance is provided.
TORQUE REQUIREMENTS
Torque ratings are subject to variations depending on
the length of time between cycles and the media in
the system.
Breakaway torque is that force which must be exerted
to cause the ball to begin to open. Operating torque
requirements will vary depending on the length of time
between cycles, media in the system, line pressure and
type of valve seat.
MAINTENANCE
With self-wiping ball/seats, SVF valves have a long,
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But, when necessary, valves may be refurbished, using
a small number of components, none of which require
machining.
SVF valves are designed for easy service and assembly
in the field. The following checks will help to extend valve
life, or reduce plant problems.
STEM LEAKAGE
Examine the Gland/Seal adjustment for damage (see
image below). If in good condition tighten the Gland
to the torque values provided in Table A. Due to wear
and tear the Gland can become loose and will need
to be re-torqued. Further maintenance necessitates
dismantling of the valve.
The stem nut can be tightened to compress the stem
packing without removing any actuation devices. Using
the proper Gland Wrench tighten the Gland (clockwise
motion) until leakage completely stops.
LEAKAGE AT BODY JOINT
Check for tightness at the body connector bolts. If loose,
tighten body bolts. Excessive force will damage the bolts
(See Table A and Bolt Tightening Sequence). If there is
still leakage it will be necessary to dismantle the valve
and replace the body seals.
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INSTALLATION, OPERATION & MAINTENANCE FOR SVF SERIES BZ9 BALL VALVES
Gland/Seal
Adjustment