Thread Repair Coil Inserts
Thread Repair Coil Inserts
Manufacturers:
Coil inserts are helically coiled diamond-shaped wire that is inserted into an oversized tapped hole. Once in place, they will bring the inside thread of the coil back to the original thread size. Coil inserts can be used for repair of damaged threads, or for new installations to provide greater thread strength due to their high percentage of thread engagement. Made from corrosion resistant 18-8 stainless steel, these coil inserts can withstand temperatures up to 800°F. Available in both imperial and metric kits that provide inserts, a tap and installation tool. If more coils are needed, we also offer individual packs of coil inserts.
Products
Dimensional Specifications
| Internal Thread |
A | Free Coils | B | |
| Length | Free Outer Diameter | |||
| Imperial Coarse |
||||
| Min | Max | |||
| 2-56 | 0.129 | 5.250 | 0.109 | 0.113 |
| 3-48 | 0.148 | 5.000 | 0.126 | 0.134 |
| 4-40 | 0.168 | 4.750 | 0.144 | 0.149 |
| 5-40 | 0.188 | 5.500 | 0.157 | 0.165 |
| 6-32 | 0.207 | 4.750 | 0.178 | 0.183 |
| 8-32 | 0.246 | 6.000 | 0.205 | 0.210 |
| 10-24 | 0.285 | 5.000 | 0.240 | 0.248 |
| 12-24 | 0.324 | 6.000 | 0.268 | 0.275 |
| 1/4-20 | 0.375 | 5.750 | 0.314 | 0.322 |
| 5/16-18 | 0.469 | 6.625 | 0.384 | 0.392 |
| 3/8-16 | 0.563 | 7.250 | 0.455 | 0.463 |
| 7/16-14 | 0.656 | 7.375 | 0.530 | 0.538 |
| 1/2-13 | 0.750 | 7.875 | 0.600 | 0.610 |
| 9/16-12 | 0.844 | 8.250 | 0.667 | 0.679 |
| 5/8-11 | 0.938 | 8.500 | 0.742 | 0.752 |
| 3/4-10 | 1.125 | 9.375 | 0.880 | 0.892 |
| 7/8-9 | 1.313 | 10.000 | 1.019 | 1.033 |
| 1-8 | 1.500 | 10.125 | 1.162 | 1.179 |
| 1 1/8-7 | 1.688 | 9.875 | 1.315 | 1.355 |
| 1 1/4-7 | 1.875 | 11.250 | 1.443 | 1.483 |
| 1 3/8-6 | 2.063 | 10.500 | 1.598 | 1.643 |
| 1 1/2-6 | 2.250 | 11.500 | 1.716 | 1.728 |
- All dimensions are in inches.
| Internal Thread |
A | Free Coils | B | |
| Length | Free Outer Diameter | |||
| Imperial Fine |
||||
| Min | Max | |||
| 4-48 | 0.168 | 5.625 | 0.139 | 0.147 |
| 6-40 | 0.207 | 6.000 | 0.170 | 0.178 |
| 8-36 | 0.246 | 6.500 | 0.200 | 0.208 |
| 10-32 | 0.285 | 6.875 | 0.233 | 0.241 |
| 1/4-28 | 0.375 | 8.250 | 0.299 | 0.307 |
| 5/16-24 | 0.469 | 8.875 | 0.370 | 0.378 |
| 3/8-24 | 0.563 | 11.000 | 0.433 | 0.441 |
| 7/16-20 | 0.656 | 10.625 | 0.507 | 0.515 |
| 1/2-20 | 0.750 | 12.375 | 0.567 | 0.577 |
| 9/16-18 | 0.844 | 12.500 | 0.630 | 0.642 |
| 5/8-18 | 0.938 | 14.125 | 0.694 | 0.706 |
| 3/4-16 | 1.125 | 15.125 | 0.831 | 0.841 |
| 7/8-14 | 1.313 | 15.000 | 0.968 | 0.983 |
| 1-14 | 1.500 | 19.000 | 1.097 | 1.110 |
| 1-12 | 1.500 | 16.000 | 1.108 | 1.120 |
| 1 1/8-12 | 1.688 | 17.250 | 1.304 | 1.334 |
| 1 1/4-12 | 1.875 | 19.375 | 1.439 | 1.469 |
| 1 3/8-12 | 2.063 | 21.375 | 1.484 | 1.496 |
| 1 1/2-12 | 2.250 | 23.500 | 1.710 | 1.745 |
- All dimensions are in inches.
| Internal Thread |
A | Free Coils | B | |
| Length | Free Outer Diameter | |||
| Metric Coarse |
||||
| Min | Max | |||
| M2-0.4 | 3mm | 4.9mm | 2.6mm | 2.8mm |
| M2.5-04 | 3.75mm | 5.9mm | 3.3mm | 3.5mm |
| M3-0.5 | 4.5mm | 6.3mm | 3.8mm | 4mm |
| M3.5-0.6 | 5.25mm | 6.3mm | 4.55mm | 4.75mm |
| M4-0.7 | 6mm | 6.1mm | 5.15mm | 5.35mm |
| M5-0.8 | 7.5mm | 6.9mm | 6.35mm | 6.6mm |
| M6-1.0 | 9mm | 6.9mm | 7.6mm | 7.85mm |
| M7-1.0 | 10.5mm | 8.2mm | 8.65mm | 8.9mm |
| M8-1.25 | 12mm | 7.4mm | 9.85mm | 10.1mm |
| M10-1.50 | 15mm | 8.1mm | 12.1mm | 12.5mm |
| M11-1.50 | 16.5mm | 9mm | 13.1mm | 13.5mm |
| M12-1.75 | 18mm | 8.4mm | 14.4mm | 14.8mm |
| M14-2.0 | 21mm | 8.3mm | 17.2mm | 17.7mm |
| M16-2.0 | 24mm | 9.7mm | 19.4mm | 19.9mm |
| M18-2.5 | 27mm | 9mm | 21.5mm | 22mm |
| M20-2.5 | 30mm | 10mm | 23.7mm | 24.2mm |
| M22-2.5 | 33mm | 10.9mm | 26.3mm | 26.8mm |
| M24-3.0 | 36mm | 10mm | 28.6mm | 29.1mm |
| M27-3.0 | 40.5mm | 11.4mm | 32.2mm | 32.7mm |
| M30-3.5 | 45mm | 11mm | 35.2mm | 35.7mm |
| M33-3.5 | 49.5mm | 12.2mm | 38.3mm | 38.8mm |
| M36-4.0 | 54mm | 11mm | 42.1mm | 42.6mm |
| M39-4.0 | 58.5mm | 12.2mm | 45.1mm | 45.6mm |
- All dimensions are in millimeters.
| Internal Thread |
A | Free Coils | B | |
| Length | Free Outer Diameter | |||
| Metric Fine |
||||
| Min | Max | |||
| M8-1.0 | 12mm | 9.5mm | 9.85mm | 10.1mm |
| M10-1.25 | 15mm | 9.7mm | 12.1mm | 12.5mm |
| M12-1.5 | 18mm | 6.2mm | 14.4mm | 14.8mm |
| M14-1.5 | 21mm | 7.4mm | 17.2mm | 17.7mm |
| M16-1.5 | 24mm | 13mm | 19.4mm | 19.9mm |
| M18-2.0 | 27mm | 11.2mm | 21.5mm | 22mm |
| M20-2.0 | 30mm | 12.5mm | 23.7mm | 24.2mm |
| M22-2.0 | 33mm | 13.6mm | 26.3mm | 26.8mm |
| M24-2.0 | 36mm | 15mm | 28.6mm | 29.1mm |
- All dimensions are in millimeters.
Installation
1. Drill out the hole with the specified drill.
2. Confirm that the thread and pitch of the bolt match the tap.
3. Tap the hole with the specified tap.
4. Set the stop on the installation tool so the tang is centered in the slot.
5. Wind the insert into the hole with a slight downward pressure until 1/4 to 1/2 turn below the surface.
6. Remove the tang by placing the tang break tool (or installation tool) on top of the tang and striking firmly with a hammer.