Precipitation Hardening Bolting (UNS N07718) for High Temperature Service
ASTM A1014 / A1014M covers Precipitation Hardening Bolting (UNS N07718) for High Temperature Service. AS 7467 Bolts And Screws is also reffered for Nickel Alloy, UNS N07718 Tensile Strength 185 KSI [1275 MPa] Stress Rupture Rated Procurement Specification. Bolting material alloy shall be multiple-melted using consumable electrode practice in the remelt cycle or shall be induction melted under vacuum. If consumable electrode re-melting is not performed in vacuum, electrodes produced by vacuum induction melting shall be used. Fully heat treated bolting material shall meet the dimensional requirements of Specification B637 for UNS N07718. Headed bolting components such as bolts, studs, or screws with a body length three times the diameter of the component or longer shall be subjected to full size tensile test and shall conform to the tensile strength as per this specification. The microstructure of the bolting material shall be free of freckles, white spots, and Laves phases. Threads of bolting components may show evidence of cold working as a result of rolling. The average grain size shall be determined in accordance with Test Methods E112 and found to be ASTM No. 5 or finer. Up to 20 % of the structure may have a grain size as large as a No. 3 due to the presence of non-crystallized grains. Bolting components produced from forgings shall exhibit continuous flow lines in the threads and in any shank to head or fillet and/or bearing surface areas.
| Element | UNS N07718 (Formerly Grade 718) |
|---|---|
| C, max. | 0.08 |
| Mn, max. | 0.35 |
| Si, max. | 0.35 |
| P, max. | 0.015 |
| S, max. | 0.015 |
| Cr | 17.0-21.0 |
| Co, max.A | 1.0 |
| Mo | 2.80-3.30 |
| Nb + | 4.75-5.50 |
| Ta | . . . |
| Ti | 0.65-1.15 |
| Al | 0.20-0.80 |
| B, max. | 0.006 |
| FeB | Remainder |
| Cu, max. | 0.30 |
| NiC | 50.0-55.0 |
|
|
| Properties | Room Temperature | Elevated Temperature |
|---|---|---|
| Tensile strength, min, ksi [Mpa] | 185 [1275] | 1200 [650] |
| Yield Strength, min, ksi, [Mpa] 0.2 % offset | 150 [1035] | 125 [860] |
| Elongation in 2 in., or 50 mm (or 4D) min % | 12 | 12 |
| Reduction of area, min, % | 15 | 15 |
| Hardness, Brinell | 331-444 | ... |
Product Shall be Marked with our manufacturing trade mark "TorqBolt" or "TB" along with the designated Grade.
Grade and manufacturer’s identification symbols shall be applied to one end of studs and to the heads of bolts and screws of all sizes. (If the available area is inadequate, the grade symbol may be marked on one end and the manufacturer’s identification symbol marked on the other end.) For bolts and screws smaller than 1⁄4 in. [6 mm] in diameter and studs smaller than 3⁄8 in. [10 mm] in diameter and for 1⁄4 in. [6 mm] in diameter studs requiring more than a total of three symbols, the marking shall be a matter of agreement between the purchaser and the manufacturer.
B18.31.2 Imperial Continious Thread, Double End Reduced & Full Body Studs
B18.31.1M Metric Continious Thread, Double End Reduced & Full Body Studs
B16.5 Imperial Full Thread Stud Bolts
B16.5 Metric Full Thread Stud Bolts
B18.2.1 Imperial Square and Hex Bolts and Screws
B18.2.3.1M Metric Hex Cap Screws
B18.2.3.3M Metric Heavy Hex Screws
B18.2.3.5M Metric Hex Bolts
B18.3 Imperial Hexagon Socket and Spline Socket Screws
B18.3.1M Metric Socket Head Cap Screws
B18.6.7M Metric Machine Screws
B18.2.2 Imperial Square, Hex, Heavy Hex, Lock, Heavy Hex Lock Nuts
B18.2.4.1M Metric Hex Nuts
B18.2.4.6M Metric Heavy Hex Nuts
ISO 4033 Hexagon High Nuts
ISO 4032 Hexagon Nuts
ISO 4035 Hexagon Lock Nuts
E18 Test Methods for Rockwell Hardness of Metallic Materials
E21 Test Methods for Elevated Temperature Tension Tests of Metallic Materials
E112 Test Methods for Determining Average Grain Size
E292 Test Methods for Conducting Time-for-Rupture Notch Tension Tests of Materials
E709 Guide for Magnetic Particle Testing
A962/A962M Specification for Common Requirements for Bolting Intended for Use at Any Temperature from Cryogenic to the Creep Range
A788/A788M Specification for Steel Forgings, General Requirements
ASME B1.1 Unified Inch Screw Threads (UN and UNR Thread Form)
ASME B1.3 Screw Thread Gaging System for Dimensional Acceptability - Inch Screw Threads (IN, UNR, and UNJ)
ASME B1.13M Metric Screw Threads - M Profile
ASME B1.21M Metric Screw Threads - MJ Profile
ASME B1.2 Gages & Gauging for Unified Screw Threads (Imperial)
| S1 | Protective Atmosphere |
|---|---|
| S2 | Cleaning |
| S3 | Fillet Rolling |
| S4 | Forged Heads |
| S5 | Marking |
| S6 | Thread Rolling |