Pipe
Clearance between the outside diameter of flange and the outside diameter of pipe to the insulation should not be less than 0′- 1″* (25mm)
Clearance between the outside diameter of pipe, flange, or insulation and structural any member should not be less than 0′- 2″* (50mm)
*With full consideration of thermal movements
Clearance between the outside diameter of flange and the outside diameter of pipe to the insulation should not be less than 0′- 1″* (25mm)
Clearance between the outside diameter of pipe, flange, or insulation and structural any member should not be less than 0′- 2″* (50mm)
*With full consideration of thermal movements
Platforms
Minimum width for ladder to ladder travel: 2′- 6″ (800mm)
Headroom: 7′- 0″ (2.1m)
Headroom from stairwell treads: 7′- 0″ (2.1m)
Minimum clearance around any obstruction on dead end platforms: 1′- 6″ (500mm)
Pressure Instruments
Locate all local pressure indicators so they are visible from grade, permanent ladder, or platform. Those located less than 15 feet (4.5m) above high point of finished surface should be accessible from grade or a portable ladder. Those located in a pipeway should be considered accessible by portable ladder. Those over 15 feet (4.5m) above high point of finished surface should be accessible from a platform or permanent ladder.
Locate all local pressure indicators so they are visible from grade, permanent ladder, or platform. Those located less than 15 feet (4.5m) above high point of finished surface should be accessible from grade or a portable ladder. Those located in a pipeway should be considered accessible by portable ladder. Those over 15 feet (4.5m) above high point of finished surface should be accessible from a platform or permanent ladder.
Process Units
The relation of units, location of equipment, and routing of pipe should be based on economics, safety, and ease of maintenance, operation, and construction requirements. The alignment of equipment and routing of pipe should offer an organized appearance.
The relation of units, location of equipment, and routing of pipe should be based on economics, safety, and ease of maintenance, operation, and construction requirements. The alignment of equipment and routing of pipe should offer an organized appearance.
Process Unit Piping
Locate all pipe lines in major process units on overhead pipeways. In certain instances, pipes may be buried, providing they are adequately protected. Lines that must be run below grade, and must be periodically inspected or replaced, should be identified on the P&IDs and placed in covered concrete trenches.
Cooling water lines normally may be run above or below ground, based on economics.
Domestic or potable water and fire water lines should be run underground.
Locate all pipe lines in major process units on overhead pipeways. In certain instances, pipes may be buried, providing they are adequately protected. Lines that must be run below grade, and must be periodically inspected or replaced, should be identified on the P&IDs and placed in covered concrete trenches.
Cooling water lines normally may be run above or below ground, based on economics.
Domestic or potable water and fire water lines should be run underground.
Pumps
Locate pumps close to the equipment from which they take suction. Normally, locate pumps in process units under pipeways.
Design piping to provide clearance for pump or driver removal. Similarly, on end suction pumps, piping should permit removing suction cover and pump impeller while the suction and discharge valves are in place.
Arrange suction lines to minimize offsets. The suction lines should be short and as direct as possible, and should step down from the equipment to the pump. Suction lines routed on sleeperways may rise to pump suction nozzle elevation.
Orient valve handwheels or handles so they will not interfere with pump maintenance or motor removal. Valve handwheels or handles should be readily operable from grade.
Maintenance and operating aisles with a minimum width of 2′-6″ (800mm) should be provided on three sides of all pumps.
Locate pumps close to the equipment from which they take suction. Normally, locate pumps in process units under pipeways.
Design piping to provide clearance for pump or driver removal. Similarly, on end suction pumps, piping should permit removing suction cover and pump impeller while the suction and discharge valves are in place.
Arrange suction lines to minimize offsets. The suction lines should be short and as direct as possible, and should step down from the equipment to the pump. Suction lines routed on sleeperways may rise to pump suction nozzle elevation.
Orient valve handwheels or handles so they will not interfere with pump maintenance or motor removal. Valve handwheels or handles should be readily operable from grade.
Maintenance and operating aisles with a minimum width of 2′-6″ (800mm) should be provided on three sides of all pumps.
Pump Strainers
Provide temporary conical type strainers in 2 inch (50mm) and larger butt weld pump suction lines for use during startup. Arrange piping to facilitate removal.
Use permanent Y-type strainers on 2 inch (50mm) and smaller screwed or socket weld pump suction piping.
Provide temporary conical type strainers in 2 inch (50mm) and larger butt weld pump suction lines for use during startup. Arrange piping to facilitate removal.
Use permanent Y-type strainers on 2 inch (50mm) and smaller screwed or socket weld pump suction piping.
Railroads
Headroom over through-railroads (from top rail) 22′- 6″** (7m)
Clearance from track centerline to obstruction 10′- 0″** (3m)
(** Verify conformance with local regulations)
Headroom over through-railroads (from top rail) 22′- 6″** (7m)
Clearance from track centerline to obstruction 10′- 0″** (3m)
(** Verify conformance with local regulations)
Relief Valves (Pressure, Safety and Thermal)
Locate all relief valves so they are accessible. Wherever feasible, locate them at platforms that are designed for other purposes. Relief valves with a centerline elevation over 15 feet (4.5m) above high point of finish surface (except in pipeways) should be accessible from platform or permanent ladder.
Pressure relief valves that discharge to a closed system should be installed higher than the collection header. There should be no pockets in the discharge line.
Safety relief valves (in services such as steam, etc.) that discharge to the atmosphere should have tail pipes extended to a minimum of 8 feet (2.5m)above the nearest operating platform that is within a radius of 25 feet (7.5m). This requirement may be waived, provided a review of the proposed arrangement indicates that it does not present a hazard. Review all pressure and safety relief valves discharging flammable vapors to the atmosphere within 100 feet (30m) of fired equipment for vapor dissipation.
Pressure and Safety relief valves, 1-1/2 inch (40mm) and larger, should only be installed with the stem and body vertical position.
Thermal relief valves, 1 inch (25mm) and smaller, may be installed with the stem and body in a horizontal position when it is impractical to install it in the vertical position.
Locate all relief valves so they are accessible. Wherever feasible, locate them at platforms that are designed for other purposes. Relief valves with a centerline elevation over 15 feet (4.5m) above high point of finish surface (except in pipeways) should be accessible from platform or permanent ladder.
Pressure relief valves that discharge to a closed system should be installed higher than the collection header. There should be no pockets in the discharge line.
Safety relief valves (in services such as steam, etc.) that discharge to the atmosphere should have tail pipes extended to a minimum of 8 feet (2.5m)above the nearest operating platform that is within a radius of 25 feet (7.5m). This requirement may be waived, provided a review of the proposed arrangement indicates that it does not present a hazard. Review all pressure and safety relief valves discharging flammable vapors to the atmosphere within 100 feet (30m) of fired equipment for vapor dissipation.
Pressure and Safety relief valves, 1-1/2 inch (40mm) and larger, should only be installed with the stem and body vertical position.
Thermal relief valves, 1 inch (25mm) and smaller, may be installed with the stem and body in a horizontal position when it is impractical to install it in the vertical position.
Roads
Major process plants normally have three classes of roads. They might be called Primary roads, Secondary roads and Maintenance access ways.
Major process plants normally have three classes of roads. They might be called Primary roads, Secondary roads and Maintenance access ways.
Clearance or distance required
Road type Vertical Width Shoulder Side or off road Primary 21′-0″ (6.5m) 20′-0″ (6m) 5′-0″ (1.5m) 20′-0″ (6m) Secondary (*) 12′-0″ (3.7m) 12′-0″ 3.7m) 3′-0″ (1m) 10′-0″ (3m) Maintenance access 10′-0″ (3m) 10′-0″ (3m) (not req’d) 5′-0″ (1.5m)(*) Normally secondary plant roads may be used as tube pull areas.
Safety Access
Provide a primary means of egress (continuous and unobstructed way of exit travel) from any point in any building, elevated equipment, or structure. A secondary means of escape should be provided where the travel distance from the furthest point on a platform to an exit exceeds 75 feet (25m).
Access to elevated platforms should be by permanent ladder. Safety cages should be provided on all ladders over 15′-0″ (4.5m)
The need for stairways should be determined by platform elevation, number of items requiring attention, observation and adjustment, and the frequency of items.
Ladder safety devices such as cable reel safety belts and harnesses, may be investigated for use on boiler, flare stack, water tank, and chimney ladders over 20 feet (6m) in unbroken lengths in lieu of cage protection and landing platforms.
Provide a primary means of egress (continuous and unobstructed way of exit travel) from any point in any building, elevated equipment, or structure. A secondary means of escape should be provided where the travel distance from the furthest point on a platform to an exit exceeds 75 feet (25m).
Access to elevated platforms should be by permanent ladder. Safety cages should be provided on all ladders over 15′-0″ (4.5m)
The need for stairways should be determined by platform elevation, number of items requiring attention, observation and adjustment, and the frequency of items.
Ladder safety devices such as cable reel safety belts and harnesses, may be investigated for use on boiler, flare stack, water tank, and chimney ladders over 20 feet (6m) in unbroken lengths in lieu of cage protection and landing platforms.
Sample Connections
Locate all sample connections so they are readily accessible from grade or platform.
In general, where liquid samples are taken in a bottle, locate the sample outlet above a drain funnel to permit free running of the liquid before sampling.
Hot samples should be provided with a cooler.
Locate all sample connections so they are readily accessible from grade or platform.
In general, where liquid samples are taken in a bottle, locate the sample outlet above a drain funnel to permit free running of the liquid before sampling.
Hot samples should be provided with a cooler.
Sleeper Pipe Supports
Normally, route piping in offsite areas on sleepers. Stagger the sleeper elevations to permit ease of crossing or change of direction at intersections. Flat turns may be used when entire sleeper ways change direction.
Normally, route piping in offsite areas on sleepers. Stagger the sleeper elevations to permit ease of crossing or change of direction at intersections. Flat turns may be used when entire sleeper ways change direction.
Spectacle Blinds
Locate spectacle blinds to be accessible from grade or platform. Blinds located in a pipeway are considered accessible. Blinds that weigh over 100 lbs (45kg) should be accessible by mobile equipment. Where this is not possible, provide davits or hitching points.
Closely grouped flanges with blinds should be staggered.
Locate spectacle blinds to be accessible from grade or platform. Blinds located in a pipeway are considered accessible. Blinds that weigh over 100 lbs (45kg) should be accessible by mobile equipment. Where this is not possible, provide davits or hitching points.
Closely grouped flanges with blinds should be staggered.
Steam Traps
Locate all steam traps at all pocketed low points and at dead ends of steam headers. Also, provide traps periodically on excessively long runs of steam piping, for sufficient condensate removal, and to ensure dry quality steam at destination. Steam traps should be accessible from grade or a platform. Steam traps located in pipeways should be considered accessible by portable ladder.
Locate all steam traps at all pocketed low points and at dead ends of steam headers. Also, provide traps periodically on excessively long runs of steam piping, for sufficient condensate removal, and to ensure dry quality steam at destination. Steam traps should be accessible from grade or a platform. Steam traps located in pipeways should be considered accessible by portable ladder.
Tankage
Locate any tankage containing hydrocarbon or other combustible fluids or gasses a minimum distance of 250′-0″ (115m) from any process unit, rail loading facility or truck loading facility.
The minimum spacing of offsite storage tanks and dike requirements should be in accordance with the latest edition of the National Fire Protection Association, Code No. 30, and OSHA part 1910.106 (b), where applicable.
Locate any tankage containing hydrocarbon or other combustible fluids or gasses a minimum distance of 250′-0″ (115m) from any process unit, rail loading facility or truck loading facility.
The minimum spacing of offsite storage tanks and dike requirements should be in accordance with the latest edition of the National Fire Protection Association, Code No. 30, and OSHA part 1910.106 (b), where applicable.
Temperature Instruments
Locate temperature test wells, temperature Indicators and thermocouples to be accessible from grade or a portable ladder. Those located in a pipeway should be considered accessible by a portable ladder. Those located over 15 feet (7m) above high point of finished surface should be accessible from a platform or permanent ladder.
Locate all local temperature indicators (TI) should be visible from grade, ladder, or platform.
Locate temperature test wells, temperature Indicators and thermocouples to be accessible from grade or a portable ladder. Those located in a pipeway should be considered accessible by a portable ladder. Those located over 15 feet (7m) above high point of finished surface should be accessible from a platform or permanent ladder.
Locate all local temperature indicators (TI) should be visible from grade, ladder, or platform.
Towers (See Vertical Vessel)
Utility Stations
Provide and locate utility stations with water, steam, or air as indicated below:
All areas should be reachable with a single 50 foot (20m) length of hose from the station.
Provide water outlets at grade level only, in pump areas, and near equipment that should be water washed during maintenance.
Provide steam outlets at grade level only in areas subject to product spills, and near equipment that requires steaming out during maintenance.
Provide air outlets in areas where air-driven tools are used such as at exchangers, both ends of heaters, compressor area, top platform of reactors, and on columns at each manway.
Hose, hose rack, and hose connections should be provided by the client or be purchased to match the clients existing hardware.
Provide and locate utility stations with water, steam, or air as indicated below:
All areas should be reachable with a single 50 foot (20m) length of hose from the station.
Provide water outlets at grade level only, in pump areas, and near equipment that should be water washed during maintenance.
Provide steam outlets at grade level only in areas subject to product spills, and near equipment that requires steaming out during maintenance.
Provide air outlets in areas where air-driven tools are used such as at exchangers, both ends of heaters, compressor area, top platform of reactors, and on columns at each manway.
Hose, hose rack, and hose connections should be provided by the client or be purchased to match the clients existing hardware.
Valve Handwheel Clearance
Clearance between the outside of hand wheel and any obstruction (knuckle clearance) should be 0′- 3″ (80mm)
Clearance between the outside of hand wheel and any obstruction (knuckle clearance) should be 0′- 3″ (80mm)
Valve Operation
Locate operating valves requiring attention, observation, or adjustment during normal plant operation (noted on the P&IDs) so they may be within easy reach from grade, platform, or permanent ladder as follows:
- 2″ (50mm) and smaller may be located reachable from a ladder.
- 3″ (80mm) and larger must be reachable and operable on a platform
Operating valves with the bottom of handwheel is over 7 feet (2.1m)above high point of finished surface or operating platform may be chain-operated.
The centerline of handwheel or handles on block valves used for shutdown only, located less than 15 feet (4.5m) above high point of finished surface, and those located in pipeways, may be accessible by portable ladder.
The centerline of handwheel or handles on block valves used for shutdown only and located over 15 feet (4.5m) above high point of finished surface, except those located in pipeways, should be operable from permanent ladder or platform.
In general, keep valve handwheels, handles, and stems out of operating aisles. Where this is not practical, elevate the valve to 6′- 6″ (plus or minus 3 inches) clear from high point of finished surface to bottom of handwheel.
Locate operating valves requiring attention, observation, or adjustment during normal plant operation (noted on the P&IDs) so they may be within easy reach from grade, platform, or permanent ladder as follows:
- 2″ (50mm) and smaller may be located reachable from a ladder.
- 3″ (80mm) and larger must be reachable and operable on a platform
Operating valves with the bottom of handwheel is over 7 feet (2.1m)above high point of finished surface or operating platform may be chain-operated.
The centerline of handwheel or handles on block valves used for shutdown only, located less than 15 feet (4.5m) above high point of finished surface, and those located in pipeways, may be accessible by portable ladder.
The centerline of handwheel or handles on block valves used for shutdown only and located over 15 feet (4.5m) above high point of finished surface, except those located in pipeways, should be operable from permanent ladder or platform.
In general, keep valve handwheels, handles, and stems out of operating aisles. Where this is not practical, elevate the valve to 6′- 6″ (plus or minus 3 inches) clear from high point of finished surface to bottom of handwheel.
Vents and Drains
The P&IDs should indicate, locate and size all vents, drains, and bleeds required for process reasons and plant operation.
Provide plugged hydrostatic vents and drains without valves at the high and low points of piping.
Provide valved bleeds at control valve stations, level switches, level controllers, and gage glasses per job standard.
The P&IDs should indicate, locate and size all vents, drains, and bleeds required for process reasons and plant operation.
Provide plugged hydrostatic vents and drains without valves at the high and low points of piping.
Provide valved bleeds at control valve stations, level switches, level controllers, and gage glasses per job standard.
Vertical Vessel (Column) Piping and Platforms
Locate vertical vessels in the equipment rows on each side of the pipeway in a logical order based on the process and cost. The largest vessel in each equipment row should be used to set the centerline location of all vertical vessels in that equipment row. This largest vertical vessel should be set back from the pipe rack a distance that allows for; any pumps, the pump piping, an operation aisle between the pump piping and any piping in front of the vessel, the edge of the vessel foundation and half the diameter of this the largest vessel. Set all other vertical vessels in this same equipment row on the same centerline.
Provide a clear access area at grade for vessels with removable internals or for vessels requiring loading and unloading of catalyst or packing.
Provide vessel davits for handling items such as internals and relief valves on vessels exceeding a height of 30 feet (9m) above the high point of the finished surface, and on vessels not accessible by mobile crane. Orient davits to allow the lowering of appurtenances into the access area.
WalkwaysLocate vertical vessels in the equipment rows on each side of the pipeway in a logical order based on the process and cost. The largest vessel in each equipment row should be used to set the centerline location of all vertical vessels in that equipment row. This largest vertical vessel should be set back from the pipe rack a distance that allows for; any pumps, the pump piping, an operation aisle between the pump piping and any piping in front of the vessel, the edge of the vessel foundation and half the diameter of this the largest vessel. Set all other vertical vessels in this same equipment row on the same centerline.
Provide a clear access area at grade for vessels with removable internals or for vessels requiring loading and unloading of catalyst or packing.
Provide vessel davits for handling items such as internals and relief valves on vessels exceeding a height of 30 feet (9m) above the high point of the finished surface, and on vessels not accessible by mobile crane. Orient davits to allow the lowering of appurtenances into the access area.
Walkways should have a 2′-6′ (1m) horizontal clearance (not necessarily in a straight
line) and headroom of 7′- 0″ (2.1m)
Read more: http://www.egpet.net/vb/threads/4080-General-Guidelines-for-Equipment-and-Piping-Location-Spacing-Distances-and-Clearanc?s=4f812e85e1c95dc658d3d0a8855d8581#ixzz1QcZMR4SO
you may also like: MOST READ
