This regulation is applicable to the setting of gate valve, globe valve, ball valve, butterfly valve and pressure reducing valve in petrochemical plant.Check valve, safety valve, regulating valve, trap set see the relevant provisions.These provisions do not apply to the setting of valves on underground water supply and drainage pipelines.

1 Valve arrangement principle

1.1 The valve should be set according to the type and quantity as shown in the pipeline and instrument flow chart (PID).When PID has specific requirements for the installation location of some valves, should be set according to the process requirements.

1.2 Valves should be placed in a place that is easily accessible, easy to operate and maintain.Valves in rows of pipes should be centrally located and consider operating platforms or ladders.

2 Valve installation position requirements

2.1 When the pipe gallery pipe of the inlet and outlet device is connected with the main pipe gallery in the whole factory, a cut-off valve shall be set.The installation position of the valve should be centrally arranged on one side of the unit area, and necessary operation platform or maintenance platform should be set.

2.2 Valves requiring frequent operation, maintenance and replacement should be located where the ground, platform or ladder is easily accessible.Pneumatic and electric valves should also be located in easily accessible places.

2.3 Valves that do not require regular operation (only for on-off use) and where temporary ladders can be erected if they are not operable on the ground.

2.4 The height between the center of the valve handwheel and the operating surface is 750 ~ 1500mm, and the most appropriate height is

1200mm, not requiring regular operation of the valve installation height up to 1500 ~ 1800mm.When the installation height cannot be lowered and frequent operation is required, the operating platform or step should be set at design time.The pipe of dangerous medium and the valve on the equipment shall not be set within the height of the head of the person.

2.5 When the center of the valve handwheel is more than 1800mm from the operating surface, sprocket operation should be set. The chain of the sprocket should be about 800mm from the ground. Sprocket hook should be set to hang the lower end of the chain on the nearby wall or column, so as not to affect the passage

2.6 For the valve set in the trench, the handwheel of the valve should not be lower than 300mm under the trench cover when the trench cover plate is opened for operation. When it is lower than 300mm, the valve extension rod should be set so that the handwheel is within 100mm under the trench cover plate.

2.7 For the valve set in the pipe trench, when it needs to be operated on the ground or installed below the floor (platform) of the upper floor, the valve extension rod can be set to extend to the trench cover plate, floor plate and platform for operation. The manual wheel base of the extension rod should be 1200mm.Valves with nominal diameters less than and equal to DN40 and threaded connections should not be operated with sprockets or extension rods to avoid damage to the valve.In general, valves should be operated as rarely as possible with sprockets or extension rods.

2.8 The distance between the valve handwheels arranged around the platform and the edge of the platform should not be greater than 450mm.When the valve stem and hand wheel reach into the upper part of the platform and the height is less than 2000mm, they should not affect the operation and passage of the operator, so as to avoid personal injury.

Setting requirements for large valves

3.1 The operation of large valve should use the gear transmission mechanism, and the space position required by the transmission mechanism should be considered when setting.In general, valves larger than the following class sizes should be considered with a geared drive.

3.2 Large valves shall be supported on one or both sides of the valve. The support shall not be set on the short pipe that needs to be removed during maintenance, and the support of the pipe shall not be affected when the valve is removed.The distance between bracket and valve flange should be more than 300mm.

3.3 The installation location of large valves should be a place where cranes are used, or a davit or beam should be considered.

Requirements for setting valves on horizontal lines

4.1 Unless there are other special requirements in the process, the handwheel of the valve installed on the horizontal pipe shall not face down, especially the valve on the dangerous medium pipe shall not face down.The bearing of the valve handwheel shall be determined in the following order: vertical upward;Level;Vertical upward sloping left and right 45°;Vertical downward sloping left and right 45°;Don't go straight down.

4.2 For horizontally mounted stem type valves, the stem shall not affect passage when the valve is open, especially if the stem is located on the operator's head or knee.

Other requirements for valve setting

5.1 The valves on the pipeline should be arranged in parallel, and the center line should be as even as possible. When the valves are arranged adjacent, the net distance between the handwheels should not be less than 100mm;Valves may also be staggered to reduce pipe spacing.

5.2 The valves that are technically required to be connected with the pipe mouth of the equipment shall be directly connected with the pipe mouth of the equipment when the nominal diameter, nominal pressure and sealing surface type are the same or matched with the pipe mouth flange of the equipment.When the valve is a concave flange, request that the equipment be professionally equipped with a convex flange at the corresponding orifice.

5.3 Except for special process requirements, the valves on the bottom pipes of towers, reactors, vertical vessels and other equipment shall not be arranged in the skirt.

5.4 When the branch pipe is drawn from the main pipe, the shutoff valve should be located on the horizontal section of the branch pipe close to the root of the main pipe, so that the fluid can drain out to both sides of the valve.

5.5 The branch pipe shutoff valve on the pipe gallery is not operated frequently (only used for parking inspection). If there is no permanent ladder, the space for temporary ladder should be considered.

5.6 When the high-pressure valve is opened, the starting power is large. Support must be set to support the valve and reduce the starting stress. The installation height should be 500 ~ 1200mm.

5.7 The fire water valves and fire steam valves in the device boundary area shall be distributed in a safe area accessible to operators in case of accidents.

5.8 The valve set of the steam distribution pipe for fire fighting in the heating furnace shall be easy to operate, and the distance between the distribution pipe and the furnace body shall not be less than 7.5m.

5.9 When threaded valves are installed in piping, a live joint must be installed near the valve for removal.

5.10 Sandwich-type valves or butterfly valves shall not be directly connected with the flanges of other valves and fittings, and a section shall be added in the middle

Short pipe with flanged ends.

5.11 The valve should not bear the applied load, in order to avoid excessive stress damage the valve.