Wire thread inserts, also known as threaded inserts, are internal thread fasteners made of cold-rolled diamond-shaped stainless steel wire wound into a spring shape. Materials include stainless steel, phosphor bronze, and Inconel X750 alloys. By forming an elastic connection between the screw and the internal thread of the bolt, they eliminate thread machining errors and improve shock resistance and wear resistance. Simultaneously, they distribute stress to protect the bolt thread, significantly extending service life. When used with low-strength materials such as aluminum, magnesium alloys, and plastics, they can increase the tensile strength of the internal thread from 1394N to 2100N.
This product is functionally divided into standard type (FR) and locking type (SL), the latter using a locking coil to apply pressure to the bolt to prevent loosening. Structurally, it is divided into tailed type (with installation shank) and tailless type (bidirectional installation). Installation requires a special tap, wrench, and break-off tool, and the steps include drilling, tapping, and breaking off the installation shank. The formed internal thread conforms to ISO, UN, and G standards, and the marking method follows domestic and international standards. It is widely used in aerospace, automotive manufacturing, medical equipment, and electronic products.