ITT Goulds Pumps IC, Инструкция по установке, эксплуатации и обслуживанию

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Example: Discharge piping equipment
Correct Incorrect
1
2
3
4
1. Bypass line
2. Shut-off valve
3. Check valve
4. Discharge isolation valve
2
1
1. Check valve (incorrect position)
2. The isolation valve should not be positioned
between the check valve and the pump.
4.6.5 Bypass-piping considerations
When to use a bypass line
Provide a bypass line for systems that require operation at reduced flows for prolonged periods. Con-
nect a bypass line from the discharge side (before any valves) to the source of suction.
When to install a minimum-flow orifice
You can size and install a minimum-flow orifice in a bypass line in order to prevent bypassing exces-
sive flows. Consult your ITT representative for assistance in sizing a minimum-flow orifice.
When a minimum-flow orifice is unavailable
Consider an automatic recirculation control valve or solenoid-operated valve if a constant bypass
(minimum-flow orifice) is not possible.
4.6.6 Auxiliary-piping checklist
Precautions
CAUTION:
• Risk of heat generation, seal failure, and possible physical injury. Sealing systems
that are not self-purging or self-venting, such as plan 23, require manual venting prior
to operation.
• Running a mechanical seal dry, even for a few seconds, can cause seal failure and
physical injury. Never operate the pump without liquid supplied to the mechanical
seal.
4.6 Piping checklists
44 Model IC, ICI, ICH, ICIH Installation, Operation, and Maintenance Manual