Instruction Manual Form 5191 September 1999
Design CAV4
Design CAV4 Control Valve Contents Introduction
.............................. 1 Scope of Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Installation
TYPE 657 ACTUATOR
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Principle of Operation
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Maintenance
.............................. 5 Packing Lubrication . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Packing Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . 6 Packing Replacement . . . . . . . . . . . . . . . . . . . . . . . 7 Trim Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Trim Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Use of Flushing Trim . . . . . . . . . . . . . . . . . . . . . . . 13
Parts Ordering . . . . . . . . . . . . . . . . . . . . . . . . . . . Parts Kits
14
DESIGN CAV4 CONTROL VALVE
W2700-1*/IL
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Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
14
Figure 1. Design CAV4 Control Valve with Type 657 Actuator
Description
Scope of Manual This manual includes installation, maintenance, and parts ordering information for the Design CAV4 control valve and Cavitrol IV trim. Information on the flushing trim is also provided. Refer to separate manuals for information concerning the actuator, positioner, and other accessories used with this control valve. Only personnel qualified through training or experience should install, operate, and maintain a Design CAV4 control valve. If you have any questions about these instructions, contact your Fisher Controls sales office or sales representative before proceeding.
The Design CAV4 control valve, shown in figure 1, is an angle valve with soft metal-to-metal seats, Cavitrol IV trim, cage guiding, and push-down-to-close valve plug action. Figure 8 shows a typical balanced TSO (tight shutoff) trim construction. Figure 10 shows three additional valve plug constructions that are available: one with a pressure-assisted spring-loaded PTFE seal ring with PEEK (poly ether ether ketone) anti-extrusion rings, another with five graphite piston rings, and a third with stem-balancing. Cavitrol IV trim is most often used to eliminate cavitation damage on liquid service where the differential pressure drop is greater than 207 bar, differential (3000 psi). It may also be used in applications with lower pressure drops where its anti-cavitation performance is required. Figure 11 shows the valve with
D100384X012
Introduction