Thread Sewing

Sewability is a key performance for filament polyester and bonded nylon 66 sewing threads. During high-speed sewing, the sewing thread is subjected to intense friction and heat generation due to the rapid penetration of the sewing machine needle through the test material. This heat, combined with mechanical impact, affects the thread’s sewability. 

Sewability can be tested under specified conditions, including sewing speed, needle size, stitch length, and test material. Under identical conditions, the sewability of the thread is determined by the total length (in meters) sewn before thread breakage occurs.

‌Grading of Sewability Test Results‌:

‌Grade 5‌: The average breakage length of three samples reaches or exceeds 40 meters.

‌Grade 4‌: The average breakage length of three samples is below 40 meters but above 30 meters.

‌Grade 3‌: The average breakage length of three samples is below 30 meters but above 20 meters.

‌Grade 2‌: The average breakage length of three samples is below 20 meters but above 10 meters.

‌Grade 1‌: The average breakage length of three samples is below 10 meters.

From this, it is evident that threads of the same counts tested under identical conditions achieve higher grades when they demonstrate better sewability. Factors influencing sewability include the thread’s uniformity, tensile strength, twist level, oil content rate, and elongation rate.

 Sewability    Filament Polyester Sewing Thread    Bonded Nylon 66 Thread