1. General requirements for valves
(1) The valve should be located in a place where it is easy to operate, install and maintain. The valves on the rows of pipelines should be arranged in a centralized manner, which is conducive to the installation of operating platforms and ladders.
(2) There are process operation requirements and locking requirements for some valves' positions, and they should be arranged and marked according to PID instructions.
(3) The valves on the bottom pipes of towers, reactors, vertical vessels and other equipment should not be arranged in the group seat.
(4) Manual valves that need to be operated according to the instructions of the local instrument should be located close to the local instrument.
(5) The regulating valve and safety valve should be arranged on the ground or platform where it is convenient for maintenance and adjustment. The layout of the trap should comply with the provisions of Chapter 15 in the "Regulations for the Design of Piping Layout of Chemical Plants" (HG/T20549.5).
(6) Valves used for fire hydrants or fire fighting should be located in the place where they can be safely approached in the event of a fire.
(7) The valve of the buried pipeline should be located in the valve well, and there should be room for maintenance.
(8) The valve should be located at a place where the thermal displacement is small.
(9) When there are bypass components on the valve, for example, gear transmission valves, sufficient installation and operation space should be reserved for the bypass components.
2. Position requirements for valves
(1) The installation height of the valve stem's centerline on the standpipe should be in the range of 0.7 to 1.6 m above the ground or platform, and the valve of DN40 and below can be arranged below 2 m. When the position is too high or too low, a platform or control device such as a sprocket or extension rod should be installed to facilitate operation.
(2) When there are very few valves that are operated infrequently and their operating height is not more than 2.5m from the ground; it is inconvenient to set up another permanent platform, portable ladders or mobile platforms should be used to enable people to operate them.
(3) The center of the valve handwheel arranged around the operating platform should not be greater than 400 mm from the edge of the operating platform. When the valve stem and handwheel extend above the platform and the height is less than 2 m, they should not affect the operator's operation and traffic safety.
(4) When the valves are arranged adjacently, the clear distance between the handwheels should not be less than 100 mm.
(5) The valve stem should not be installed vertically or inclined downward.
(6) For valves installed in pipe trenches or valve wells that are frequently operated, when the handwheel is lower than 300 mm below the cover plate, an extension rod should be installed to make it within 100mm under the cover plate.
(2) There are process operation requirements and locking requirements for some valves' positions, and they should be arranged and marked according to PID instructions.
(3) The valves on the bottom pipes of towers, reactors, vertical vessels and other equipment should not be arranged in the group seat.
(4) Manual valves that need to be operated according to the instructions of the local instrument should be located close to the local instrument.
(5) The regulating valve and safety valve should be arranged on the ground or platform where it is convenient for maintenance and adjustment. The layout of the trap should comply with the provisions of Chapter 15 in the "Regulations for the Design of Piping Layout of Chemical Plants" (HG/T20549.5).
(6) Valves used for fire hydrants or fire fighting should be located in the place where they can be safely approached in the event of a fire.
(7) The valve of the buried pipeline should be located in the valve well, and there should be room for maintenance.
(8) The valve should be located at a place where the thermal displacement is small.
(9) When there are bypass components on the valve, for example, gear transmission valves, sufficient installation and operation space should be reserved for the bypass components.
2. Position requirements for valves
(1) The installation height of the valve stem's centerline on the standpipe should be in the range of 0.7 to 1.6 m above the ground or platform, and the valve of DN40 and below can be arranged below 2 m. When the position is too high or too low, a platform or control device such as a sprocket or extension rod should be installed to facilitate operation.
(2) When there are very few valves that are operated infrequently and their operating height is not more than 2.5m from the ground; it is inconvenient to set up another permanent platform, portable ladders or mobile platforms should be used to enable people to operate them.
(3) The center of the valve handwheel arranged around the operating platform should not be greater than 400 mm from the edge of the operating platform. When the valve stem and handwheel extend above the platform and the height is less than 2 m, they should not affect the operator's operation and traffic safety.
(4) When the valves are arranged adjacently, the clear distance between the handwheels should not be less than 100 mm.
(5) The valve stem should not be installed vertically or inclined downward.
(6) For valves installed in pipe trenches or valve wells that are frequently operated, when the handwheel is lower than 300 mm below the cover plate, an extension rod should be installed to make it within 100mm under the cover plate.
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