First, the steel pipe is opened with a hole punching machine, and then the mechanical tee is inserted into the hole, and the hole is sealed along the pipe wall by a sealing ring. Mechanical tee is divided into two types: wire connection and groove type. When the mechanical tee is connected, the clearance between the mechanical tee and the hole should be checked, all parts should be uniform, and then tightened in place; the distance between the mechanical tee and the hole should not be less than 1m.

Mechanical tee connections are widely used in fire hydrant systems and sprinkler systems in buildings. The branch pipe joint refers to the saddle-shaped split connector that connects the branch pipe after opening the hole in the middle of the straight pipe. It is divided into two types: mechanical tee and mechanical four-way. Grooved tee and mechanical tee are generally not marked on design drawings. There are two ways to connect the mechanical tee or mechanical spool to the branch pipe: groove connection and threaded connection. When the branch pipe is smaller than DN50 and the diameter of the main pipe is greater than 2 times the diameter of the branch, the mechanical tee (open directly on the main pipe) can be used. Holes, spray branch pipes are often used to connect with the main pipe), in other cases, grooved tee should be used. The grooved tee here is a regular tee (the center line of the main branch pipe is at a right angle), because unlike UPVC pipes and cast iron pipes, in addition to the regular triangle, there are also Y tee (oblique tee) and TY tee.

The regular tee is the same as the tee of galvanized fittings, except that the galvanized tee is a threaded connection, while the regular tee here is a grooved connection, and the annular groove of the flat end of each pipe is formed by a special rolling groove machine. , The connection with the pipeline requires 3 pairs of clamps of corresponding specifications to complete a joint, which is suitable for the connection of the main pipe. As for the main pipe of the mechanical tee, it is only necessary to use a drilling machine to open holes without grooves, and branch pipes or grooves (groove connection) or threading (threaded connection) are suitable for the connection between main and branch pipes (such as spraying system). spray branch). In addition, there is a small mechanical tee, which just replaces the clamp with a U-shaped clip. In my opinion, the connection between this small mechanical tee and the branch pipe is still mainly threaded, and there may be no groove connection. The regular tee generally refers to the three nozzles with the same diameter, while the reducing tee means that the three nozzles have different diameters. The regular tee is used for the connection of pipes of the same diameter, and the reducing tee is used for the connection of pipes of different diameters. The branch pipe diameter of a mechanical tee connection can never be equal to the main pipe diameter.