Helical insert is a fastener made of helically drawn coiled wire. Helically formed coils of diamond shaped stainless steel or phosphor bronze wire screw into a threaded hole to form a mating internal thread for a screw or stud.
These inserts provide a convenient means of repairing stripped-out threads and are also used to provide stronger
threads in soft materials such as aluminum, zinc die castings, wood, plastic, magnesium etc. than can be obtained by direct tapping of the base metal involved. Other common generic names are Screw Thread Insert (STI) and Wire Thread Insert. Its applications include engine cylinder head repair after unintentional over-torque or cross-threading of spark plugs strips the thread of the socket. Thread Repairing Kits with matched tap and coil exist for this application and many others, where either a damaged thread is repaired or a new thread is formed.
STAINLESS STEEL WIRE THREAD HELICAL INSERTS MADE FROM AISI 304 / 316 GRADE STEEL
RAPI-COIL threading inserts provide means for protecting and strengthening all types of tapped
Our inserts are manufactured from 18-8 stainless steel (AISI 304 / AISI 316 / DTD 734A / AMS 7245)
and other materials all conforming to international Screw Thread Specs of DIN-8140-1 and others.
Available types – Free Running & Screw Locking
Inserts with Tang and without Tang (Tangless)
Nominal Length – 1.0D, 1.5 D, 2.0 D, 2.5D, & 3D sizes available
All sizes and pitches available in MM and IMPERIAL
Metric, Imperial, UNC, UNF, BSW, BSF, BA, BSP and BSCycle threads