Technical Instructions
Flowrite VF599 Series Three-Way Valves
Document Number 155-160P25
2-1/2 to 6-inch Flanged Iron Body
June 10, 2003
Page 8
Siemens Industry, Inc.
Sizing
The sizing of a valve is important for correct system operation. An undersized valve will
not have sufficient capacity at maximum load. An oversized valve may initiate cycling
and the seat and throttling plug can be damaged because of the restricted opening.
Correct sizing of the control valve for actual expected conditions is considered essential
for good control.
Some variables which must be determined are:
•
The medium to be controlled: water, etc.
•
The maximum inlet temperature and pressure of the medium at the valve.
•
The pressure differential that will exist across the valve under maximum load
demand.
•
The maximum capacity the valve must deliver.
•
The maximum line pressure differential the valve actuator must close against.
•
See AB-1
Control Valve Selection and Sizing
(Document Number
155-285
) for
further recommendations.
See Tables 6 and 7 for valve capacities.
Mounting and
Installation
•
Install the valve so that the flow follows the direction of the arrow indicated on the
valve body identification tag.
•
For best performance, install the valve assembly with the actuator above the valve
body. The valve and actuator can be installed in any position between vertical and
horizontal. Siemens Building Technologies does not recommend installing the valve
assembly below horizontal or upside down.
•
If installing a service flange, see Table 13 for proper placement.
•
For flange dimensions and bolt hole information, see
155-303P25
(
TB 248
)
.
Allow
sufficient space for servicing the valve and actuator. See Table 12 for valve body
dimensions. See Figure 5 and Table 11 for dimensions of the service envelope
recommended around the actuator.
•
A lower seat tool is required for removing a three-way valve. See Table 10 for part
numbers.
NOTE:
Instructions for field mounting an actuator, spring adjustments, wiring diagrams,
and start-up are covered in the Technical Instructions and Installation
Instructions for each actuator.
Table 10. Three-Way Valve Lower Seat Tool.
Part Number
Valve Size
Inches (mm)
599-09144
2-1/2 (65)
599-09145
3 (75)
599-09146
4 (100)
599-09147
5 (125)
599-09148
6 (150)
