7 Wrong Installation Methods of Industrial Valves

There are many things to note when installing the valve. Today we will introduce 7 taboos of industrial valve installation.

Taboo 1:

The main materials, equipment and products used in construction lack technical quality appraisal documents or product certifications that meet the current standards issued by the country or the ministry.

Consequences: The quality of the project is unqualified, there is a hidden danger of accidents, it cannot be delivered and used on schedule, and it must be reworked for repairing, causing delays in the construction period and increasing labor and material inputs.

Measures: The main materials, equipment and products used in water supply, drainage and sanitary engineering shall have technical quality appraisal documents or product certifications that meet the current standards issued by the country or the ministry. Product names, models, specifications, and national quality standards, code, date of manufacture, name and location of the manufacturer, inspection certificate or code of the manufactured product shall be indicated.

Taboo 2:

Do not perform necessary quality inspection according to regulations before valve installation.

Consequences: The valve switch is not flexible, the closure is not strict, and water leakage (steam) occurs during system operation, which causes rework and repair, and even affects normal water supply (steam).

Measures: Before the valve is installed, the pressure strength and tightness test should be performed. The test shall be carried out by random inspection of 10% and not less than one in each batch (same brand, same specification, same model). For closed-circuit valves installed on the main pipe, the strength and tightness tests should be performed one by one. The strength and tightness test of the valve shall comply with the "Code for Acceptance of Construction Quality of Building Water Supply and Drainage and Heating Engineering" (GB 50242-2002).

Taboo 3:

The specifications and models of the installed valves do not meet the design requirements. For example, the nominal pressure of the valve is less than the system test pressure, when the pipe diameter is less than or equal to 50mm, the gate valve is used for the water supply branch, the shut-off valve is used for hot and dry pipes.

Consequences: It will affect the normal opening and closing of the valve and adjusting resistance, pressure and other functions. It even causes valve damage during system operation and forced repair.

Measures: Familiar with the application scope of various valves, and choose the specifications and models of the valves according to the design requirements. The nominal pressure of the valve should meet the requirements of the system test pressure. According to the requirements of the construction code: a stop valve should be used for the pipe diameter of the water supply branch pipe less than or equal to 50mm, a gate valve should be used when the pipe diameter is greater than 50mm.

Taboo 4:

Incorrect valve installation method. For example, the flow direction of water (steam) of the stop valve or check valve is opposite to the mark, the valve stem is installed downward, the horizontally installed check valve is installed vertically, there is no open or closed space for the handle of the open gate or butterfly valve, and the valve stem of the concealed valve does not face the inspection door.

Consequences: The valve fails, the switch is difficult to repair, and the valve stem often causes water leakage.

Measures: Install strictly in accordance with the valve installation instructions.

Taboo 5:

Ordinary valve flanges are used for butterfly valve flanges.

Consequences: The size of the butterfly valve flange is different from that of the ordinary valve flange, and some flanges have small internal diameters, while the butterfly valve has a large disc, which can cause the valve to fail to open or hard to open.

Measures: The flange should be processed according to the actual size of the butterfly valve flange.

Taboo 6:

No holes or embedded parts are reserved in the construction of the building structure, or the size of the reserved holes is too small and the embedded parts are not marked.

Consequences: During the construction of heating and sanitary engineering, it may cut off the reinforced steel bars, affecting the safety performance of the building.

Measures: Familiarize with the construction drawings of the heating and sanitary engineering. According to the needs of the installation of pipelines and hangers, take the initiative to carefully cooperate with the reserved holes and embedded parts in the construction of the building structure.

Taboo 7:

When the pipe is welded, the misalignment of the pipe behind the counterpart is not on a center line, there is no gap in the counterpart, the thick-walled pipe is not shoveled, and the width and height of the welding gap do not meet the requirements of the construction code.

Consequence: The misalignment of the pipe is not directly on the center line, which directly affects the welding quality. There is no gap at the mouth, no beveling for thick-walled pipes, and the welding can not meet the strength requirements when the width and height of the welding gap do not meet the requirements.

Measures: After welding the pipe counterparts, the pipes must not be staggered. A gap must be left on the center line of the pipe. Thick-walled pipes must be shoveled. In addition, the width and height of the welding gap should be in accordance with the requirements.