| Diameter | Pitch
(mm) | Thread Form | Length | Style | Material |
| 4 | 40 | UNC (Unified National Coarse) | 1.5D | Free Running - Tanged | Stainless Steel |
Length explained
The length of a wire thread insert is calculated as a multiple of the diameter:
e.g. M8 x 1.5D the insert length = 12mm;
e.g. M8 x 2D the insert length = 16mm
About our Free Running Thread Repair Inserts
Sometimes referred to by the brand names of Helicoilï¾® or Recoilï¾®, helically-coiled wire thread inserts are a thread strengthening fastening device used to create high strength threads in softer core materials. The high performance internal thread provided by our wire inserts is far stronger than most parent materials, and is also heat, corrosion, and wear resistant too.
Quickly and permanently restore stripped, worn or damaged threads to their original size and condition.
Our standard free running wire thread inserts are produced from Austenitic Stainless Steel wire (304/A2 Stainless), which is cold drawn (profiled) to form a diamond-shaped wire. This wire is then helically coiled to produce the wire thread insert. The stainless steel inserts eliminate thread wear, corrosion, galling and rust.
Larger in diameter than the tapped hole, the insert is compressed during installation to ensure maximum surface contact between the flanks of the wire insert and tapped threads. Once fitted, the action of the radial pressure between the insertï¾’s coils and flanks of the tapped hole holds them in place securely.
The flexibility of our inserts enhances load bearing capacity by deflecting the residual forces into a helical direction, which is dispersed into the wall of the tapped hole.
