We offer precisely made Stud Bolts, Hex Bolts, Heavy Hex Bolts, Socket Head Cap Screws, Threaded Rods, Nuts & Washers as per ASTM A453 Grade 668 Class A and B. We produce these Grade 668 Bolts from 3/8" to 4" in imperial and upto M100 in metric sizes. Larger size bolts can be made to order as per request. We also undertake custom made boltings in A453 as per drawing. We stock premium and surplus bar stock in Grade 668 (UNS S66285) for quick manufacturing and shorter delivery periods. These ASTM A453 Grade 668 Bolts are supplied with EN 10204 Type 3.1 MTC. We offer Rupture Test Facility for sufficient quantity order.
| Grade 668 | Class A | Class B |
| Element | |
|---|---|
| Content % | |
| Grade 668 UNS S66285 |
|
| Carbon | 0.08 max |
| Manganese | 2.00 max |
| Phosphorus | 0.04 max |
| Sulfur | 0.03 max |
| Silicon | 1.00 max |
| Nickel | 17.50 - 21.50 |
| Chromium | 13.50 - 16.00 |
| Molybdenum | 1.50 max |
| Tungsten | --- |
| Titanium | 2.20 - 2.80 |
| Columbium* | --- |
| Aluminum | 0.50 max |
| Vanadium | 0.50 max |
| Boron | 0.001 - 0.010 |
| Copper | --- |
* Or Columbium plus Tantalum
| Grade | Class | Tensile Strength | Yield Strength | Elongation in 4D, min, % |
Reduction of Area, min, % |
Brinell Hardness Number |
Approximate Rockwell Hardness, B & C |
|||
|---|---|---|---|---|---|---|---|---|---|---|
| Ksi | Mpa | Ksi | Mpa | min | max | |||||
| Grade 668 | A and B | 130 | 895 | 80 | 858 | 15 | 18 | 248-321 | 24 HRC | 37 HRC |
| Grade | Class | Solution Treatment | Hardening Treatment |
|---|---|---|---|
| Grade 668 | A | 1650 +/- 25° F [900 +/- 14°C], hold 2 hr, min and liquid quench | 1325 +/- 25° F [720 +/- 14°C], hold 16 hr, air cool |
| Grade 668 | B | 1800 +/- 25° F [980 +/- 14°C], hold 1 hr, min and liquid quench | 1325 +/- 25° F [720 +/- 14°C], hold 16 hr, air cool |
This Grade does not requirement rupture test.
| Grade | Class A | Class B | Class C | Class D |
|---|---|---|---|---|
| Grade 668 | FB 668A NR | FB 668B NR |