(1) The valve should be located in a place that is easily accessible, easy to operate and maintain. The valves on the pipelines (such as the pipelines into and out of the device) should be centrally arranged and the operating platforms and ladders should be considered. Parallel arrangement of the valve on the pipe, the center line should be as far as possible. The distance between the handwheels should not be less than 100mm. In order to reduce the distance between the pipes, the valve can be staggered;

(2) Valves used to cut off equipment shall be connected directly to the nozzle of the equipment when conditions permit, or as close as possible to the equipment. In this way, more pipelines can be tested during the hydrostatic test of the system, and the equipment can also be removed (or separated) without affecting the system during maintenance.

(3) Accident handling valves such as fire water valves, fire steam valves, etc. shall be arranged in a decentralized manner, taking into account the safe operation during an accident. Such valves shall be arranged behind the control room, behind the security wall, outside the factory door, or in a zone with a certain safety distance from the accident site, so that when a fire accident occurs, the operator can operate safely;

(4) The valves on the bottom pipelines of towers, reactors, vertical containers, etc., shall not be arranged in the skirts;

(5) The branch pipe led from the trunk pipe is generally close to the root and a shut-off valve is provided on the horizontal pipe section;

(6) The lift check valve shall be installed on the horizontal pipeline. The vertical lift check valve may be installed on the vertical pipeline where the medium flows from bottom to top. Swing check valve shall be installed on the horizontal pipe preferentially, or it may be installed on the vertical pipe that the medium flows from bottom to top; the bottom valve shall be installed on the riser end of the centrifugal pump suction pipe;

(7) The center of the handwheel of the valve arranged around the operating platform shall not be greater than 450mm from the edge of the operating platform. When the stem and the handwheel protrude above the platform and the height is less than 2 meters, it shall not affect the operation and passage of the operator. (8) The valves of the underground pipelines shall be located in the trenches or in the valve wells. If necessary, valve extension rods shall be provided. Fire valve wells should have clear signs. The optimum installation height of the valve is about 1.2 meters from the operating surface. The valve on the horizontal pipe, the direction of the stem can be determined in the following order: vertical upwards; horizontal; inclined upward 45°; downward inclined 45°; A horizontally mounted open-rod valve, when the valve is open, must not affect the passage of the valve stem. Operator operation and access;

(9) The valve of the underground pipeline shall be located in the trench or in the valve well. If necessary, a valve extension rod shall be provided. Fire valve wells should have clear signs. The optimum installation height of the valve is about 1.2 meters from the operating surface. The valve on the horizontal pipe, the direction of the stem can be determined in the following order: vertical upwards; horizontal; inclined upward 45°; downward inclined 45°; A horizontally mounted open-rod valve, when the valve is open, must not affect the passage of the valve stem.