Globe valve, throttle valve, pressure reducing valve, check valve and other valves are directional, if installed upside down, throttle valve will affect the service effect and life;Relief valves do not work and check valves can be dangerous. General valve, on the valve body has direction marking;If not, the valve should be correctly identified according to the working principle. The valve chamber of the globe valve left and right asymmetry, the fluid to let it from the bottom up through the valve port, so that the fluid resistance is small (by the shape of the decision), open energy saving (due to the media pressure upward), closed after the media pressure packing, easy to repair.This is why the globe valve cannot be installed backwards.Other valves have their own characteristics. Valve must be installed in a position that is easy to operate;Even if the installation is temporarily difficult, keep the operator's long-term work in mind. Best valve handwheel and chest (generally from the operation floor 1.2 meters), so that the valve is more energy saving.Landing valve handwheel to face up, do not tilt to avoid awkward operation.Rely on the wall machine by the valve of the equipment, also want to leave the operator standing room.To avoid operation, especially acid and alkali, toxic media, otherwise it is not safe. Gate valves should not be inverted (i.e., handwheel down), as this will leave medium in the bonnet space for a long time, prone to corrosion of the stem, and is prohibited by some technical requirements.It is extremely inconvenient to replace the packing at the same time. 1, the pressure reducing valve to be installed upright in the horizontal pipeline, all directions do not tilt. 2, lifting check valve, installation to ensure that the disc is vertical, so as to lift flexible. 3, swing type check valve, installation to ensure that the pin shaft level, in order to swing flexible. 4, open stem gate valve, do not install in the ground, or due to moisture and corrosion exposed stem.