NIBCO Bronze, Globe and Angle Valves 1/ to Class 175 WWP - Manual (Page 5)

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2.0 INSTALLATION
2.1
PRELIMINARY INFORMATION
The globe and angle valves should preferably be installed with the stem pointed
vertically upward. However, it is normally acceptable to have the valve stem pointed in a
horizontal position either in vertical or horizontal piping. Although a globe and angle
valve will function satisfactorily in an inverted position it is not generally recommended
because it allows fluids to become trapped in the bonnet cavity which results in
contamination and the inability to fully drain the system.
To operate satisfactorily, the special model non-return (N .R.) can only be installed in the
vertical position because gravity allows the disc to fall when the flow reverses. This
feature also makes this valve directional and must be installed with fluid flow in the same
direction as the flow arrow on the side of the valve.
Valves are shipped in the closed position to prevent damage to the seating surfaces.
There is no internal blocking used for shipment. All NIBCO valves are shipped in
cardboard boxes for protection against exterior damage and accumulation of dust or dirt
on the delicate seating surfaces. The boxes are not waterproof and, therefore, require
that they be protected from the weather.
2.2 HANDLING AND INSTALLATION
Each valve should be handled very carefully and not dropped or thrown into a dirty
environment before it is assembled into the system. Under no circumstances should the
valve be installed into the line by wrenching through the valve body, this means that
when a valve is being threaded onto a pipe, the wrench should be on the end where the
joint is being made.
It is very important to make certain that the threads of the pipe are clean at all times and
machined properly. When improperly tapered pipe is screwed into the female threads
the pipe can be driven too deeply and ruin the seats of the valve. Care should also be
used to assure that the valve is not over-tightened because the steel pipe is much
stronger than the bronze material, therefore, the bronze will distort and cause valve
malfunction or leakage at the joint. When screwing the valve onto the pipe, the disc
should remain in the closed position.
On solder end type valves it is necessary to make sure that the valve disc is in the open
position while it is being heated for soldering into the line. The major caution here is that
the valve not be overheated and that the proper amount of solder is used so that it does
not flow into the valve rendering it inoperable.
NIBCO globe valves should be installed for optimal performance based on the general
application, water or steam.
For steam service applications: The flow should enter the valve so that it can assist in
sealing the disc against the seat. In other words, steam flow should arrive on top of the
disc so that it pushes the disc down into the seat, to help seal the valve in the closed
position.