Installation Guide for Valves

Low Temperature Welding and Silver Brazing

Be sure to keep in mind what the recommended valve is for and analyze the application environment in order to determine which valve is most suitable for installation. Before installing the correct valve, in order to prevent damage to the valve, move the pump truck and ensure full performance of the valve, please read the installation guide.

1. Cut the pipe along the vertical direction, trim and remove burrs, and measure the diameter of the pipe.

2. Use gauze or wire brush to remove pipes and cutting parts to make the metal surface shine. It is recommended not to use steel wool.

3. Coating flux on the outside of the pipe and the inside of the welding cover, the flux must cover the welding surface completely. Please use flux sparingly.

4. Make sure the valve is open. First heat the pipe. Transfer as much heat as possible from the pipe to the valve. Avoid prolonging the heating time of the valve itself.

4a. Method of silver Brazing:

Assemble parts that need brazing. If the parts coated with flux are allowed to stand upright, the water in the flux will evaporate, and the dry flux will fall off easily, resulting in the exposed metal surface being easily oxidized. In connection assembly, the pipe is inserted into the sleeve until obstruction is encountered. Assembly is to ensure a solid support, so that the whole brazing operation can be maintained in a straight line position.

Note: For valves of 1 inch or larger nominal diameter, it is difficult to heat the connecting parts to the required temperature at one time. In order to maintain normal temperature over a large area, two torches are usually required. Suggestions are made for proper preheating of the whole sleeve area. It is suggested that acetylene flame be used to heat the connecting parts. Firstly, the pipeline is heated from an inch away from the valve, then the pipeline is fired alternately up and down in short distance around the pipeline, and the pipeline is rotated at an appropriate angle to avoid burning through the pipeline. Flames should move continuously and not be allowed to stay at a certain point.

The sleeve base of the valve is baked by flame. The heating should be uniform, and the flame baking process of the valves and pipes should continue to the flux on the valves without making any noise. Do not overheat the valve.

When the flux becomes liquid and translucent on pipes and valves, the flame is baked in and out along the axis of the connecting parts to maintain the heat of the connecting parts, especially the base of the valve sleeve.

5. Use appropriate amount of solder: If the self-priming pump truck uses linear solder, then the valve with nominal diameter of 3/4 inch should use 3/4 inch solder, and so on. If too much solder is used, some solder may flow through the blocking part of the pipe and block the sealing area. The solder and brazing alloys can be seen continuing to flow when connecting parts are installed.

Flange connection

In order to ensure the correct installation of valve flange connection, the following steps need to be followed. First, carefully clean the connection, then loosely install two or three bolts on the base. Next, carefully insert the gasket into the connection. Bottom bolts help to locate the gasket and keep it in proper position. Then insert the bolt in a cross-tightening way, not around the tightening way, which helps to eliminate excessive concentration of pressure. After a period of normal use, check whether all the bolts are tightened and do the necessary re-tightening.