M&H 4500, Руководство пользователя

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SECTION 2
INSTALLATION OF M&H MODEL 4500 &1450 BFVS
SECTION 2.1 – GENERAL
Butterfly valves are an important part of any water distribution system or treatment plant operation. Valve
failure due to faulty installation, improper operation, or maintenance in such systems could result in
damage, down time, and costly repairs. In buried or underground installations, problems or malfunctions
can result in extensive and costly unearthing operations to correct or eliminate the problem. Many
problems with butterfly valves can be traced to improper installation, operation, or maintenance
procedures.
Make sure flange faces, joint sealing surfaces, body seats, and vane are clean. Check bolting attaching
operator for loosening in transit and handling. If loose, tighten firmly. Open and close valve to make sure
it operates properly and that the stops or limit switches are set correctly so the valve fully closes and seats.
Close the valve before installing. For dry operation prior to installation, it is suggested that an NSF61
approved lubricant be applied to the rubber seat before moving the vane.
Handle valves carefully when positioning, avoiding contact or impact with other equipment, vault walls,
or trench walls.
M&H BFVs are rated for the designated operating pressure with flow in either direction. The
mechanically retained seat on the vane provides for adjustment or replacement with relative ease. It is
recommended that BFVs be installed with the seat side positioned for best access to the seat for future
maintenance.
Foreign material in a butterfly valve can damage the rubber seat when valves are operated. Be sure
interiors and adjacent piping is cleaned of foreign material prior to assembling the pipe joint connection.
SECTION 2.2 – UNLOADING & STORAGE
Inspect valves on receipt for damage in shipment and conformance with quantity and description of the
shipping notice and order. Unload all valves carefully to the ground without dropping. For valves 36
inches and larger, use forklifts or slings under skids. For smaller valves, do not lift valves with slings or
chains around the operating shaft, operator, or through waterway. Lift these valves with eyebolts or rods
through the flange holes.
After securing the valve with the chosen lifting method, always assume the valve can fall despite your
best effort to secure the valve. It is critically important to never be too close to, or under, the valve being
lifted due to the potential for failure of the lifting mechanism being used.
Protect the valve and operators from weather and the accumulation of dirt, rocks, and debris. When valves
fitted with power operators and controls are stored, energize electric operators or otherwise protect
electrical control equipment to prevent corrosion of electrical contacts due to condensation resulting from
temperature variation.