normally sized to not exceed the flow capacity of the downstream drip
legs to handle the condensate collection during the initial startup of the
Steam header control valves and pressure regulators should be provided
with upstream stainers. Pressure regulators should have upstream drip
legs and manual bypass lines.
Stream traps should provide adequate capacity to accommodate
condensation loads during warm-up as well as during normal operation
and to compensate for line size, length, and insulation type and
thickness. Traps for end user equipment (e.g., heating coils) normally
accommodate full condensate load from the equipment warm-up in order
to be considered automatic draining.
Arimid fiber gasket material should not be used in any steam or
Various devices can be used to protect piping systems from damage
caused by severe hydraulic transients. Check valves, standpipes, and
accumulators can prevent the occurrence or reduce the effect of a
Vacuum-breaker valves should be used in situations where water-column
separation can occur. Check valves (preferably titling disc) can also be
used to prevent column separation in the event of power loss.
Purge Systems. Chemical processing vessels in nonreactor facilities often handle
materials that are both flammable and potentially explosive. An effective way of
controlling the potential for fire and explosions in these vessels is either to control the
fuel in the tank by diluting and sweeping the vapor space with purge gas or to limit the
oxygen content in the vapor space by blanketing with an inert gas. The type of purge