Notes before installation

Before installation, check carefully whether the valve’s model, designed pressure and caliber meet the requirements. Make sure the arrowmark on the valve point at the flow direction of the pipe medium.

Before installation, make sure the chamber and sealing surface are clean, check the sealing surface, bolt connection, packing compression, stem rotation, etc.

The valve on horizontal pipeline, its stemis betterto be vertically upward. Downward stem not onlybarsoperation, maintenance,but also hurtsthe valveitself .

The valve installed on the pipeline should have the space for operation, maintenance and disassembly. The reserved space of handwheel should not be less than 100mm.

For flanged end valves, users should select bolts and gaskets according to the temperature, pressure and medium, and tighten the connecting bolts and nuts evenly.

For valves with butt-end construction, customers shall weld and heat-treat according to standard requirements. Welding shall be performed by qualified personnel and shall be performed only after process qualification.

Pay attention to the location indicator while open and close valve. Overuse of "F" wrench can easily lead to distortion of bellows and damage of internal parts.

Notes for installation

After the installation of the valve, when the medium temperature is greater than 100℃, the packing gland should be gently open, fully evaporating the water in the cavity formed by the bellows and packing, and then tight on the packing gland.

Bellows sealed globe valves,bellows sealed gate valvesmust be full open or closed during system or line pressure test. They are not allowed tot be partially opened to regulate flow.

Usually bellows sealed valves do not have an insulated part.so that do not touch the surface of the valve when the medium is a high or low temperature fluid.

The surface and moving parts of the valve, such as the trapezoidal threads of the valve stem and the valve stem nut, the sliding parts of the valve nut and support, are easy to accumulate dust, oil stains and residual media stains, which are easy to cause wear and corrosion of the valve and even generate friction heat, this is very dangerous to combustion gas, should be regularly cleaned according to the working conditions.

If there is water in the valve cavity, in the case of low temperature (such as the medium is liquid nitrogen), bellows sealed valves are easy to damage. Water should be drained before installation to avoid icing.

Xiamen Dervos is a leading valve maker and trader in Xiamen, southeastern China. Our wide range of high-quality products include gate valves, ball valves, shut-off pig valves, butterfly valves, and other engineered products for the oil and gas industry. For more information regarding our products, contact us today.