STEAM SYSTEM PIPING
SCOPE
This is a general guide for the design and installation of steam systems.
STEAM
· Live steam supply and exhaust steam return headers shall be located on overhead pipe racks and shall have block valves at the process unit limit.
· Wherever possible, live steam and exhaust steam tines shall be the outside lines of the overhead pipe rack in order to provide accessibility for expansion loops, pressure reducing stations and flow instrumentation.
· Live steam and exhaust steam return lines shall be connected to the top of the headers.
· Separators for removal of steam condensate ahead of turbines etc .. may be justified only at locations remote from the boiler plant or main steam supply. Separators for removal of oil from exhaust steam shall be installed just ahead of the boiler feedwater treating equipment or surge drum but will not normally be required on the exhausts of individual items of rotating equipment.
· Block valves shall be provided in branch lines from Live steam and exhaust steam headers; these shall normally be located at the steam header. Except turbine exhaust block valves shall be at the turbine only, without a block valve at the header.
· Single block and check valves shall normally be provided at the steam injection point for designated process lines. Double block and-bleed valves with a single check valve shall be provided for heavy oil services. When required by the process design.
· Steam traps shall be provided at all steam separators, header drip legs and other low points.
· Steam trap discharge and other condensate lines may be consolidated into headers and returned to the boiler feedwater system. Discharge to the waste system shall be made only if return headers are not economically feasible.
Drip legs shall be installed on steam headers as follows:
a) At dead ends.
b) Upstream of risers
c) Upstream of expansion joints or raised expansion loops.
d) Upstream of block and reducing valves
e) Every 350 feet (107 m) in straight, horizontal steam lines (I.e. without natural drainage points)
Steam for purging shall be taken from the nearest available steam supply header.
Steam smothering lines with trapped drains shall be provided to combustion chambers and header boxes of fired heaters and on safety relief valve stacks discharging flammable products to atmosphere. Valves on these steam smothering lines shall be located at least 50 feet
(15.2 m) away from the heater or stack and shall be readily accessible for emergency use by personnel.
Jurisdictional requirements (i.e. local state. And federal) shall be met in the fabrication, alteration and repair of all steam and condensate piping.
SCOPE
This is a general guide for the design and installation of steam systems.
STEAM
· Live steam supply and exhaust steam return headers shall be located on overhead pipe racks and shall have block valves at the process unit limit.
· Wherever possible, live steam and exhaust steam tines shall be the outside lines of the overhead pipe rack in order to provide accessibility for expansion loops, pressure reducing stations and flow instrumentation.
· Live steam and exhaust steam return lines shall be connected to the top of the headers.
· Separators for removal of steam condensate ahead of turbines etc .. may be justified only at locations remote from the boiler plant or main steam supply. Separators for removal of oil from exhaust steam shall be installed just ahead of the boiler feedwater treating equipment or surge drum but will not normally be required on the exhausts of individual items of rotating equipment.
· Block valves shall be provided in branch lines from Live steam and exhaust steam headers; these shall normally be located at the steam header. Except turbine exhaust block valves shall be at the turbine only, without a block valve at the header.
· Single block and check valves shall normally be provided at the steam injection point for designated process lines. Double block and-bleed valves with a single check valve shall be provided for heavy oil services. When required by the process design.
· Steam traps shall be provided at all steam separators, header drip legs and other low points.
· Steam trap discharge and other condensate lines may be consolidated into headers and returned to the boiler feedwater system. Discharge to the waste system shall be made only if return headers are not economically feasible.
Drip legs shall be installed on steam headers as follows:
a) At dead ends.
b) Upstream of risers
c) Upstream of expansion joints or raised expansion loops.
d) Upstream of block and reducing valves
e) Every 350 feet (107 m) in straight, horizontal steam lines (I.e. without natural drainage points)
Steam for purging shall be taken from the nearest available steam supply header.
Steam smothering lines with trapped drains shall be provided to combustion chambers and header boxes of fired heaters and on safety relief valve stacks discharging flammable products to atmosphere. Valves on these steam smothering lines shall be located at least 50 feet
(15.2 m) away from the heater or stack and shall be readily accessible for emergency use by personnel.
Jurisdictional requirements (i.e. local state. And federal) shall be met in the fabrication, alteration and repair of all steam and condensate piping.
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