Troubleshooting of common faults of double needle double chain Lockstitch Sewing Machine

A double-needle double chain lockstitch sewing machine is a machine widely used in the knitting industry. It is mainly suitable for decorative sewing of clothing, underwear, bedding, and so on. Broken wires, jumper pins, etc. are common faults of the machine. The common faults are analyzed and eliminated according to your own experience.

There are the following points causing disconnection.

① Fabric or stitches do not match. Adjustment method: select the suture matching the fabric.

② The sewing thread is too thick and the machine needle is too thin, and the sewing thread is too thin and the machine needle is too thick, resulting in thread breakage. Adjustment: the suture should match the needle.

③ There are burrs on the bending needle, protective needle, and needle plate, resulting in wire breakage. Adjustment: polish the edges of the curved needle, protective needle, and needle plate.

④ The sewn fabric is thick and easy to break the needle, which will roughen the curved needle and needle guard plate, resulting in thread breakage. Adjustment: polish the edges of the curved needle and guard the needle.

⑤ The threading amount of the bending needle cam is too tight or the threading method is wrong, resulting in thread breakage. Adjustment: properly loosen the threading amount of cam and thread correctly.

Needle skipping is one of the most common faults of a chain lockstitch sewing machines.

① The threading of the machine head is wrong, and the model of the needle does not match the fabric. Adjustment: thread correctly again, and use the matching machine needle and fabric.

② Adjustment of cam position. Adjustment method: the machine needle is placed at the lower needle plate, and the cam starts threading. It can also be adjusted flexibly according to the process and the thickness of the fabric in advance.

Wrinkling is rare.

① The stitch is too tight or the feeding dogs are too high. Adjustment: properly reduce the height of the feeding dog.

② The cam is poorly matched with the bottom thread or the bottom thread is not threaded correctly. Adjustment method: readjust the fit between the bottom thread and the cam, and re-thread the bottom thread according to the correct method.

Lockstitch Sewing Machine needle breakage is mostly caused by fabric.

① Whether the thickness of the needle matches the fabric. Adjustment: select the machine needle matching with the fabric.

② Whether the synchronization between the needle protector and the needle machine is correct. Adjustment: adjust the synchronous relationship between the protective needle and the machine needle according to the correct method.

③ If the needle plate hole is too small, it will affect the workpiece. Adjustment: select the matching needle plate.

④ Whether the needle and feeding are synchronized. Adjustment method: adjust the synchronous relationship between needle and feeding according to the correct method.