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responsible for damages which occur in transit. Store the equipment in a clean, dry
area.
5.1 INSTALLATION
5.1.1 Accessibility
Entire systems should be positioned to permit access to operating controls, instruments,
and inspection openings. Additional space should be allotted, if
necessary, for platforms and ladders required for otherwise inaccessible areas.
5.1.2 Foundations
Deaerator foundations need not be as massive as those required by rotating or
reciprocating machinery. The foundation should be level and designed to support the
anticipated load. Calculations should be based upon the maximum or flooded weight of
the entire system including allowances for attachments.
5.1.3 Rigging
Qualified riggers should be used to place the system on the foundation. Slings, blocks
and all rigging equipment must be carefully placed to avoid damaging or loosening
piping, nozzles and other parts of the assembly. The system should be securely bolted
to the foundation and shimmed if necessary.
5.1.4 Piping
Prior to piping, a thorough internal inspection should be made. All foreign material or
debris must be removed to prevent possible malfunctions. Care should be taken to
avoid imposing piping strain on the vessel or pumps. Provide expansion joints and
suitable independently supported pipe hangers where necessary. Isolating valves
should be installed to allow for cleaning or repairs. Valve bypasses are recommended
around water inlet and steam pressure reducing valves. Vent piping should be vertical
and full-size, avoiding any bends or restrictions. To insure continuous venting, a gate
valve is factory installed with a pre-drilled orifice in its disc to prevent complete closure.
The piping of the steam pressure-reducing valve is crucial to the proper operation of the
deaerator. In service, a pressure-reducing valve produces a lower pressure at its outlet
than at its inlet, creating a high steam velocity across the valve seat. In most reducing
valve installations, sonic velocity will occur. The extreme velocities that must exist
across reducing valve seats cannot be tolerated in piping upstream or downstream of
the valve. Excessive erosion and noise would result. In systems where noise of steam
flow would be a consideration, it is common practice to limit the velocities to between
4,000 and 6,000 feet per minute. The steam velocity chart (Table 1) lists steam
capacities in pipes under various pressure and velocity conditions.
5.1.5 Water Inlet Valve
5.1.5.1 Valve with integral float chamber
Install valve sub-assembly as shown on drawing with centerline of float chamber at
designated operating level. On systems incorporating two valves, one should be located
at the operating level, and the second approximately 2” lower. The primary valve will
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