Mechanical Systems - hdbk1132990202

DOE-HDBK-1132-99

normal supply is lost or interrupted. Typically, the following loads may be

sensitive to power interruptions and should be powered by a UPS. UPSs can

utilize converters or batteries. Batteries may be used to provide emergency

power in special facilities like telecommunication, alarm, and radio repeater

stations. Rechargeable batteries are recommended and should be maintained

fully charged at all times by float chargers. A design provision is recommended

for a portable emergency generator hook-up during an extended, planned

outage of the normal service to the battery charger.

MECHANICAL SYSTEMS

This section describes design considerations useful to mechanical design personnel

involved in the design of piping and air pollution control systems within DOE nuclear

facilities. The guidance represents good design practices and lessons learned from

various design, construction, startup, and operations experiences.

Piping.

3.1

3.1.1

Piping Systems.

Selection of an appropriate corrosion/erosion allowance is vital to the

service life of the system. Consideration of effects of temperature and

fluid velocities is very important in selecting and sizing the system

properly. For example, carbon steel piping may be acceptable for sulfuric

acid when the concentrations are above 93 percent, flow rates are below

3 feet/sec, and the temperature is below 122 EF.

Piping systems that perform safety-related functions are to be designed

and fabricated to more rigorous standards than other fluid service piping.

In accordance with ASME B31.3, Process Piping, Category M Fluid

Service may be designated for design, material and component selection,

fabrication and erection, and examination and inspection of these

systems. Certified Material Test Reports for material and components

provide additional assurance for these piping systems.

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