Flowserve 1878 Y-Pattern Globe Valves - Manual (Page 4)

1.0 PHYSICAL DESCRIPTION AND OPERATION OF EQUIPMENT
1.1
GLOBE VALVES (Figure 1)
These valves are primarily designed for tight shutoff and throttling service
where control of the velocity of the fluid is necessary. If required, they can
also serve as a means of isolating a portion of a system. Their use however,
is limited to those systems where head losses are not critical as the internal
flow passage creates a pressure drop across the valve. With the disc in the
full open or any intermediate position, the fluid is allowed to flow through
seat area at a rate determined by the position of the disc. With the disc in
the closed position, the force of the stem provides a mechanical seal
between the disc and seat and effects a shutoff at the valve.
The
½”-2” Y-Globe valves have a precision cast body. It is an investment
casting and offers smooth flow passages for minimum pressure drop and
minimum turbulence. A bellows is provided as a primary sealing device.
The
½”-2” Y-Globe valves can be provided with a variety of disc styles to
provide different throttling flow characteristics. The following three distinct
disc styles are available: quick plug type, parabolic, cage type. A circular
plate below the tee handle/handwheel nut indicates the type of disc.
All ½”-2” Y-Globe valves are supplied with a tee-handle actuator and a
bellows seal. To operate these valves, turn the tee-handle in a clockwise
direction for closure and counterclockwise for opening.
2.0
DESIGN CONDITIONS
Refer to the applicable drawings in Section 12.0 of this manual.
3.0
OPERATING CONDITIONS
Refer to the applicable drawings in Section 12.0 of this manual.
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