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NotchFlo™ DST Control Valve
Contents
Introduction
1
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Scope of Manual
1
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Description
1
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Specifications
3
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Installation
4
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Maintenance
5
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Packing Maintenance
7
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Adding Packing Rings
9
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Replacing Packing
9
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Trim Removal
12
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Valve Plug Maintenance
12
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Lapping Seats
13
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Trim Replacement
14
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Parts Ordering
15
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Parts Kits
16
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Parts List
16
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Figure 1. Fisher NotchFlo DST Control Valve
W9050
Introduction
Scope of Manual
This instruction manual includes installation, maintenance, and parts information for the Fisher NotchFlo DST control
valve. Refer to separate manuals for instructions covering the actuator, positioner, and accessories.
Do not install, operate, or maintain NotchFlo DST valves without being fully trained and qualified in valve, actuator,
and accessory installation, operation, and maintenance. To avoid personal injury or property damage, it is important
to carefully read, understand, and follow all the contents of this manual, including all safety cautions and warnings. If
you have any questions about these instructions, contact your Emerson Process Management sales office before
proceeding.
Description
The NotchFlo DST globe (figure 1) and angle valves have metal seats, cage guiding, quick change trim, and
push‐down‐to‐close valve plug action. All available valve sizes and pressure ratings use balanced valve plugs with the
exception of CL900 and CL1500 (NPS 1 and 1‐1/2 valves) which use an unbalanced valve plug. To provide a seal
between the cage and a balanced valve plug, the balanced valve plugs use a pressure‐assisted spring‐loaded seal ring.
A properly sized NotchFlo DST valve with 3‐, 4‐, or 6‐stage dirty service anti‐cavitation trim (figure 2) offers excellent
control of high pressure drop liquids with entrained solids, while avoiding the damaging effects of cavitation and
erosive solids.
Instruction Manual
D103211X012
NotchFlo DST Valve
March 2011