There are three ways to connect galvanized pipes:
1. Grooving connection
Grooving weld cracking:
① Grind the inner wall weld ribs of the grooved part of the pipe mouth to reduce the grooving resistance;
② Adjust the axis of the steel pipe and the grooving equipment, and require the steel pipe and the grooving equipment to be level;
③ Adjust the grooving speed, the grooving forming time cannot exceed the specified time, and apply force evenly and slowly.

Grooved steel pipe fracture:
① Grind the inner wall weld ribs of the grooved part of the steel pipe mouth to reduce the grooving resistance;
② Adjust the axis of the steel pipe and the grooving equipment, and require the steel pipe and the grooving equipment to be level;
③ Adjust the grooving speed, the grooving speed cannot exceed the specified time, and apply force evenly and slowly;
④ Check the width and model of the support roller and the pressure roller of the grooving equipment to see if there is a bite phenomenon caused by the mismatch of the two roller sizes;
⑤ Use a vernier caliper to check whether the groove of the steel pipe is specified.

The grooves formed by the groove rolling machine should meet the following requirements:
① The surface from the pipe end to the groove section should be flat without bumps and rolling marks;
② The center of the groove should be concentric with the pipe wall, the groove width and depth should meet the requirements, and check whether the clamp model is correct;
③ Apply lubricant on the rubber sealing ring and check whether the rubber sealing ring is damaged. The lubricant must not be oil lubricant.

2. Welding connection
① After the galvanized steel pipe mouth is butted, it is not in a straight line and there is a bevel problem in the steel pipe. It is recommended to cut off a small section of the steel pipe head before processing;
② After the galvanized steel pipe mouth is butted, the two pipe mouths are not tightly butted, resulting in an uneven thickness of the weld, and the steel pipe is caused by its reasons or transportation bumps, resulting in an elliptical pipe mouth. It is recommended to cut off a small section of the steel pipe head before processing;
③ After the galvanized steel pipe mouth is butted, sand holes appear at the pipe mouth, which is caused by technical reasons during welding;
④ There are zinc nodules at the pipe mouth, which causes welding difficulties and sand holes. For pipes with too large zinc nodules and too many pipes, simple zinc nodule removal treatment is performed.

3. Threaded connection
① Threads are randomly tied: the pipe clamp and the thread cannot be completely in contact or are loose. Cut off the randomly tied part re-thread and install;
② The steel pipe thread and the pipe clamp thread do not match and cannot be connected. The pipe clamp should be replaced or the equipment should be adjusted to re-thread;
③ The steel pipe is missing after threading: measure whether the wall thickness of the steel pipe can meet the standard thickness requirements of the threaded pipe.