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INST LL TION
The Fig 4925 and Fig 4923 are fully lugged valves and should be located between flanges utilising the flange bolt holes.
The flange bolts or studs should be tightened diagonally until the body touches the flange face with metal to metal contact.
Prior to installation, a check of the identification plate and body marking must be made to ensure that the correct valve is being
installed.
Valves are precision manufactured items and as such, should not be subjected to misuse such as careless handling, allowing dirt to
enter the valve through the end ports, lack of cleaning both valve and system before operation and excessive force during bolting and
handwheel/lever operation.
All special packaging material must be removed.
Valves must be provided with adequate support. Adjoining pipework must be supported to avoid the imposition of pipeline strains on
the valve body, which would impair its performance.
When large valves are provided with lifting lugs or eye nuts, these should be used to lift the valve.
Immediately prior to valve installation, the pipework to which the valve is to be fastened should be checked for cleanliness and freedom
from debris.
Valve packaging should only be permanently removed immediately before installation. The valve interior should be inspected through
the end ports to determine whether it is clean and free from foreign matter.
The mating flange (both valve and pipework flanges) should be checked for correct gasket contact face, surface finish and condition.
If a condition is found which might cause leakage, no attempt to assemble should be made until the condition has been corrected.
This butterfly valve has integral rubber sealing faces and gaskets must not be used.
In order to maintain an effective sealing face with the pipe flange, integral, weld-neck, slip-on or loose plate flanges should be used.
The pipe flange should cover the rubber body liner forming the gasket face of the body. If pipe other than BS EN10255 Medium Grade,
BS EN 10220 or Schedule 40 is used the gasket face may only partially covered please refer to the Hattersley Technical Dept.
Care should be taken to provide correct alignment of the flanges being assembled. Suitable lubricant on bolt threads should be used.
In assembly, bolts are tightened sequentially to make the initial contact of flanges and gaskets flat and parallel followed by gradual and
uniform tightening in an opposite bolting sequence to avoid bending one flange relative to the other, particularly on flanges with raised
faces.
Parallel alignment of flanges is especially important in the case of the assembly of a valve into an existing system.
Flanged joints depend on compressive deformation of the integral rubber sealing faces between the flange surfaces until metal to metal
contact is achieved.
The bolting must be checked for correct size, length, material and that all connection flange bolt holes are utilised.
OPER TING - GE R OPER TED
An enclosed worm gear reduction operator (gearbox) is mounted on the valve body with the gear quadrant intimately connected with
the valve shaft. The full open and full closed position travel stops are set at the factory and require no further adjustment.
Note: if the gearbox is fitted with a padlock and locking ring, the padlock will require removal prior to operation.
Valve closure is by clockwise rotation of the handwheel until the travel stop restriction is felt. No excessive force is required to effect
tight shut off and under no circumstances should a wrench or wheelkey be used.
Counter clockwise rotation of the handwheel will open the valve until the full open travel stop or to the intermediate regulated travel stop
(memory stop) if fitted on the double regulating version.
A non-adjustable pointer indicates the actual valve disc position against a fixed scale.
The memory stop (double regulating versions only) device is fitted at the factory so that the valve may be operated over its full travel
prior to commissioning without the need for adjustment.
SETTING THE GE RBOX MEMORY STOP (REFER TO FIG 1)
Slacken the setscrew 'A' sufficient to allow the position limiting plate to rotate.
The position limiting plate rotates freely on the central screw, which does not
require any adjustment.
Using the usual commissioning procedures, rotate the handwheel to
move the disc to the required position.
Ensure that the position limiting plate is in contact with the raised stop on the
indicator pointer, if not rotate the plate until it touches.
Tighten the setscrew 'A' to limit the maximum position of valve opening.
Record the regulation position.
BUTTERFLY / BUTTERFLY DOUBLE REGULATING VALVES Fig. 4925 / Fig. 4923
Installation and Operating Instructions
Fig 1
03
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