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Stainless Steel Coupling Nut | Alloy Steel Coupling Nut | Duplex Steel Coupling Nut | Carbon Steel Coupling Nut
Carbon Steel Coupling Nut
We manufacturer fasteners with size range from M10 to M100 Hex Nuts, Heavy Hex Nut, Cap Nut, Acorn Nut, Serrated Flange Nut, Coupling Nut, Square Nut, Castle Nut, Wing Nut, Flange Lock Nut, Flex Lock Nut, High Nut, Kep Nut, Jam Nut, Nylon Lock Nut, Slotted Nut, Reversible Lock Nut, Custom Nut, T Nuts & other customized Nuts as per Client's requirement.We produce Hot Forged and Coled Formed Nuts Fasteners.
Coupling Nuts
Coupling Nut Applications
Coupling nuts are used to make up long tie rod assemblies from shorter lengths of rod and to facilitate assembly of two fasteners or fittings which each have external threads.
Relevant Standards
Coupling nut dimensions are described by the Industrial Fasteners Institute in standard IFI-128. Chemical and mechanical properties are controlled in conformance with ASTM and SAE nut specifications (ASTM A563, ASTM A194 and SAE J995).
Materials
Standard coupling nuts are produced from ASTM A108 grade 12L14 hexagon or round bars with 50 Ksi minimum yield strength. Other available materials include 1045, 4140, structural grades and stainless steels.
Finishes
Standard finish is plain with either a cold drawn or hot rolled mill finish, depending on the type of bar stock used. Hot dip galvanizing is available as well as zinc electroplating.
Threads
Standard threads are UNC 2B, RH, with other thread series and profiles available by special order. Hot dip galvanized coupling nuts are normally tapped oversize after galvanizing to accommodate the zinc coating on the rod threads. Coupling nuts up to 1-1/2" thread size are tapped all the way through from one end, allowing them to be completely threaded on to one of the members which are to be coupled, a feature that is required for certain assembly situations. Coupling nuts larger than 1-1/2" thread size cannot be tapped all the way through without special extended length taps and are therefore furnished with RH/RH threads (tapped to a depth of L/2 from each end) unless specifically ordered as 'threaded all the way through'.
Coupling nuts can also be threaded with two different thread sizes or profiles. These parts are normally identified as 'reducing coupling nuts'.
Dimensions
Refer to the coupling nut table for dimensions. Some of the sizes listed in this table have an 'Across Flats Size' slightly larger than that called for by IF-128 due to commercial availability of hexagon bar stock. Because of limited availability of hex stock larger than 3-1/2", coupling nuts with thread sizes 2-1/2" and larger are usually made from round bar.
Carbon Steel
| IdentificationGrade Mark | Specification | FastenerDescription | Material | Nominal SizeRange (in.) | Mechanical Properties | ||
| Proof Load(psi) | Yield StrengthMin (psi) | Tensile StrengthMin (psi) | |||||
 NoGradeMark | SAE J429Grade 1 | Bolts,Screws,Studs | Low or Medium Carbon Steel | 1/4 thru 1-1/2 | 33,000 | 36,000 | 60,000 |
| ASTM A307Grades A&B | Low Carbon Steel | 1/4 thru 4 | — | — | |||
| SAE J429Grade 2 | Low or Medium Carbon Steel | 1/4 thru 3/4 Over 3/4 to 1-1/2 | 55,00033,000 | 57,00036,000 | 74,00060,000 | ||
| NoGradeMark | SAE J429Grade 4 | Studs | Medium Carbon Cold Drawn Steel | 1/4 thru 1-1/2 | — | 100,000 | 115,000 |
| B5 | ASTM A193Grade B5 | AISI 501 | 1/4 Thru 4 | — | 80,000 | 100,000 | |
| B6 | ASTM A193Grade B6 | AISI 410 | 85,000 | 110,000 | |||
| B7 | ASTM A193Grade B7 | AISI 4140, 4142, OR 4105 | 1/4 thru 2-1/2Over 2-1/2 thru 4Over 4 thru 7 | ——- | 105,00095,00075,000 | 125,000115,000100,000 | |
| B16 | ASTM A193Grade B16 | CrMoVa Alloy Steel | 105,00095,00085,000 | 125,000115,000100,000 | |||
| B8 | ASTM A193Grade B8 | AISI 304 | 1/4 and larger | — | 30,000 | 75,000 | |
| B8C | ASTM A193Grade B8C | AISI 347 | |||||
| B8M | ASTM A193Grade B8M | AISI 316 | |||||
| B8T | ASTM A193Grade B8T | Bolts,Screws,Studs for High-Temperature Service | AISI 321 | 1/4 and larger | — | 30,000 | 75,000 |
| B8 | ASTM A193Grade B8 | AISI 304Strain Hardened | 1/4 thr 3/4Over 3/4 thru 1Over 1 thru 1-1/4Over 1-1/4 thru 1-1/2 | ——— | 100,00080,00065,000 50,000 | 125,000115,000105,00 0100,000 | |
| B8C | ASTM A193Grade B8C | AISI 347Strain Hardened | |||||
| B8M | ASTM A193Grade B8M | AISI 316Strain Hardened | 95,00080,00065,000 50,000 | 110,000100,00095,00 090,000 | |||
| B8T | ASTM A193Grade B8T | AISI 321Strain Hardened | 100,00080,00065,000 50,000 | 125,000115,000105,000 100,000 | |||
| L7 | ASTM A320Grade L7 | Bolts,Screws,Studs for Low-Temperature Service | AISI 4140,4142 or 4145 | 1/4 thru 2-1/2 | — | 105,000 | 125,000 |
| L7A | ASTM A320Grade L7A | AISI 4037 | |||||
| L7B | ASTM A320Grade L7B | AISI 4137 | |||||
| L7C | ASTM A320Grade LC7 | AISI 8740 | |||||
| L43 | ASTM A320Grade L43 | AISI 4340 | 1/4 thru 4 | — | 105,000 | 125,000 | |
| B8 | ASTM A320Grade B8 | Bolts,Screws,Studs for Low-Temperature Service | AISI 304 | 1/4 and larger | — | 30,000 | 75,000 |
| B8C | ASTM A320Grade B8C | AISI 347 | |||||
| B8T | ASTM A320Grade B8T | AISI 321 | |||||
| B8F | ASTM A320Grade B8F | AISI 303or 303Se | |||||
| B8M | ASTM A320Grade B8M | AISI 316 | |||||
| B8 | ASTM A320Grade B8 | AISI 304 | 1/4 thru 3/4Over 3/4 thru 1Over 1 thru 1-1/4Over 1-1/4 thru 1-1/2 | ——— | 100,00080,00065,00 50,00 | 100,00080,00065,00 50,00 | |
| B8C | ASTM A320Grade B8C | AISI 347 | |||||
| B8F | ASTM A320Grade B8F | AISI 303or 303Se | |||||
| B8M | ASTM A320Grade B8M | AISI 316 | |||||
| B8T | ASTM A320Grade B8T | AISI 321 | |||||
 | SAE J429Grade 5 | Bolts,Screws,Studs | Medium Carbon Steel, Quenched and Tempered | 1/4 thru 1Over 1 to 1-1/2 | 85,00074,000 | 92,00081,000 | 120,000105,000 |
| ASTM A449 | 1/4 thru 1Over 1 to 1-1/2Over 1-1/2 thru 3 | 85,00074,000 55,000 | 92,00081,00058,000 | 120,000105,00090,000 | |||
 | SAE J429Grade 5.1 | Sems | Low or Medium Carbon Steel, Quenched and Tempered | No. 6thru 3/8 | 85,000 | — | 120,000 |
 | SAE J429Grade 5.2 | Bolts,Screws,Studs | Low Carbon Martensitic Steel, Quenched and Tempered | 1/4 thru 1 | 85,000 | 92,000 | 120,000 |
| A325 | ASTM A325Type 1 | High StrengthStructural Bolts | Medium Carbon Steel, Quenched and Tempered | 1/2 thru 11-1/8 thru 1-1/2 | 85,00074,000 | 92,00081,000 | 120,000105,000 |
| A325 | ASTM A325Type 2 | Low Carbon Martensitic Steel, Quenched and Tempered | 1/2 thru 1 | 85,000 | 92,000 | 120,000 | |
| A325 | ASTM A325Type 3 | Atmospheric Corrosion Resisting Steel, Quenched and Tempered | 1/2 thru 11-1/8 thru 1-1/2 | 85,00074,000 | 92,00081,000 | 120,000105,000 | |
 BB | ASTM A354Grade BB | Bolts,Studs | Alloy Steel, Quenched and Tempered | 1/4 thru 2-1/22-3/4 thru 4 | 80,00075,000 | 83,00078,000 | 105,000100,000 |
 BC | ASTM A354Grade BC | 105,00095,000 | 109,00099,000 | 125,000115,000 | |||
 | SAE J429Grade 7 | Bolts,Screws, | Medium Carbon Alloy Steel, Quenched and Tempered 4 | 1/4 thru 1-1/2 | 105,000 | 115,000 | 133,000 |
 | SAE J429Grade 8 | Bolts,Screws,Studs | Medium Carbon Alloy Steel, Quenched and Tempered | 1/4 thru 1-1/2 | 120,000 | 130,000 | 150,000 |
| ASTM A354Grade BD | Alloy Steel, Quenched and Tempered 4 | ||||||
| No GradeMark | SAE J429Grade 8.1 | Studs | Medium Carbon Alloy or SAE 1041 Modified Elevated Temperature Drawn Steel | 1/4 thru 1-1/2 | 120,000 | 130,000 | 150,000 |
| A490 | ASTM A490 | High Strength Structural Bolts | Alloy Steel, Quenched and Tempered | 1/2 thru 1-1/2 | 120,000 | 130,000 | 150,000 min170,000 max |
| No GradeMark | ISO R898Class 4.6 | Bolts,Screws,Studs | Medium Carbon Steel, Quenched and Tempered | All Sizesthru 1-1/2 | 33,000 | 36,000 | 60,000 |
| No GradeMark | ISO R898Class 5.8 | 55,000 | 57,000 | 74,000 | |||
| 8.8or88 | ISO R898Class 8.8 | Alloy Steel, Quenched and Tempered | 85,000 | 92,000 | 120,000 | ||
| 10.9or109 | ISO R898Class 10.9 | 120,000 | 130,000 | 150,000 | |||
FASTENER IDENTIFICATION MARKING
| GradeIdentificationMarking | Specification | Material | Nominal SizeIn. | ProofLoadStressksi | HardnessRockwell | SeeNote | |
| Min | Max | ||||||
 No Mark | ASTM A563 – Grade 0 | Carbon Steel | 1/4 thru 1-1/2 | 69 | B55 | C32 | 3,4 |
| ASTM A563 – Grade A | Carbon Steel | 1/4 thru 1-1/2 | 90 | B68 | C32 | 3,4 | |
| ASTM A563 – Grade B | Carbon Steel | 1/4 thru 1 | 120 | B69 | C32 | 3,4 | |
| over 1 thru 1-1/2 | 105 | ||||||
 | ASTM A563 – Grade C | Carbon SteelMay be Quenchedand Tampered | 1/4 thru 4 | 144 | B78 | C38 | 5 |
 | ASTM A563 – Grade C3 | AtmosphericCorrosionResistant SteelMay be Quenchedand Tampered | 1/4 thru 4 | 144 | B78 | C38 | 5,9 |
 | ASTM A563 – Grade D | Carbon SteelMay be Quenchedand Tampered | 1/4 thru 4 | 150 | B84 | C38 | 6 |
 | ASTM A563 – Grade DH | Carbon SteelQuenchedand Tampered | 1/4 thru 4 | 175 | C24 | C38 | 6 |
 | ASTM A563 – Grade DH3 | AtmosphericCorrosionResistant Steel,Quenchedand Tampered | 1/4 thru 4 | 175 | C24 | C38 | 5,9 |
 | ASTM A194 – Grade 1 | Carbon Steel | 1/4 thru 4 | 130 | B70 | — | 7 |
 | ASTM A194 – Grade 2 | Medium CarbonSteel | 1/4 thru 4 | 150 | 159 | 352 | 7,8 |
 | ASTM A194 – Grade 2H | Medium CarbonSteel, Quenchedand Tempered | 1/4 thru 4 | 175 | C24 | C38 | 7 |
 | ASTM A194 – Grade 2HM | Medium CarbonSteel, Quenchedand Tempered | 1/4 thru 4 | 150 | 159 | 237 | 7,8 |
 | ASTM A194 – Grade 4 | Medium CarbonAlloy Steel,Quenchedand Tempered | 1/4 thru 4 | 175 | C24 | C38 | 7 |
 | ASTM A194 – Grade 7 | Medium CarbonAlloy Steel,Quenchedand Tempered | 1/4 thru 4 | 175 | C24 | C38 | 7 |
 | ASTM A194 – Grade 7M | Medium CarbonAlloy Steel,Quenchedand Tempered | 1/4 thru 4 | 150 | 159 | 237 | 7 |
| See Note 1,2 | 10 | ||||||
NOTES:
- In addition to the indicated grade marking, all grades, except A563 grades O, A and B, must be marked for manufacturer identification.
- The markings shown for all grades of A194 nuts are for cold formed and hot forged nuts. When nuts are machined from bar stock the nut must be additionally marked with the letter ‘B’.
- Nuts are not required to be marked unless specified by the purchaser. When marked, the identification marking shall be the grade letter O, A or B.
- Properties shown are those of nonplated or noncoated coarse thread hex nuts.Properties shown are those of coarse thread heavy hex nuts.
- Properties shown are those of coarse thread heavy hex nuts.
- Properties shown are those of coarse 8-pitch thread heavy hex nuts.
- Hardnesses are Brinell Hardness Numbers.
- The nut manufacturer, at his option, may add other markings to indicate the use of atmospheric corrosion resistant steel.
- Specifications —
- STM A563 — Carbon and Alloy Steel Nuts.
- ASTM A194/A194M — Carbon and Alloy Steel Nuts for Bolts
for High Pressure and High Temperature Service.
| Thread Diameter ‘D’ |
Width Across Flats ‘F’ |
Width Across Points ‘G’ |
Overall Length ‘L’ |
Weight Each (lbs) |
|---|---|---|---|---|
| 1/2 | 3/4 | 7/8 | 1-1/2 | 0.12 |
| 5/8 | 1 | 1-1/8 | 1-7/8 | 0.30 |
| 3/4 | 1-1/8 | 1-5/16 | 2-1/4 | 0.42 |
| 7/8 | 1-5/16 | 1-7/16 | 2-5/8 | 0.56 |
| 1 | 1-1/2 | 1-3/4 | 3 | 0.99 |
| 1-1/8 | 1-5/8 | 1-7/8 | 3-3/8 | 1.23 |
| 1-1/4 | 1-7/8 | 2-3/16 | 3-3/4 | 1.93 |
| 1-3/8 | 2 | 2-5/16 | 4-1/8 | 2.31 |
| 1-1/2 | 2-1/4 | 2-5/8 | 4-1/2 | 3.33 |
| 1-5/8 | 2-3/4 | 3-3/16 | 4-7/8 | 6.17 |
| 1-3/4 | 2-3/4 | 3-3/16 | 5-1/4 | 6.16 |
| 1-7/8 | 3 | 3-7/16 | 5-5/8 | 7.61 |
| 2 | 3-1/4 | 3-7/16 | 6 | 9.69 |
| 2-1/4 | 3-1/2 | 4-1/16 | 6-3/4 | 12.7 |
| 2-1/2 | 3-7/8 | 4-1/2 | 7-1/2 | 17.2 |
| 2-3/4 | 4-1/4 | 4-15/16 | 8-1/4 | 22.7 |
| 3 | 4-5/8 | 5-5/16 | 9 | 29.2 |
| 3-1/4 | 5 | 5-3/4 | 9-3/4 | 36.8 |
| 3-1/2 | 5-3/8 | 6-3/16 | 10-1/2 | 45.8 |
| 3-3/4 | 5-3/4 | 6-5/8 | 11-1/4 | 56.0 |
| 4 | 6-1/8 | 7-1/16 | 12 | 68.0 |
| 4-1/2 | 6-7/8 | 7-15/16 | 13-1/2 | 96.0 |
| 5 | 7-5/8 | 8-13/16 | 15 | 130.0 |
Carbon Steel Coupling Nut Application Industries
Sunflex Metal Industries are engaged in manufacturing of robust quality of Carbon Steel Coupling Nut. These Carbon Steel Coupling Nut are widely used in the following industries:
Mining Industries Transport Industries- Rail and Road Construction Industries / Building Systems Manufacturing Industries Agriculture Industries Energy Industries Water Industries Automotive Industries Ship Building Industries Nuclear Power Plant Paper & Pulp Industries Sugar Industries Engineering Cement Industries Petro-Chemical Industries Food Industries Oil & Gas Industries Chemical & Pharmaceutical Industries
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