HEX BOLTS
ASTM A307 Grade B Heavy Hex Bolts
Grade B heavy hex bolts for specified cast-iron flange joints and related piping assemblies.
Product Overview
Grade B heavy hex bolts are a distinct procurement family for flanged piping joints using cast-iron flanges. The heavy hexagon head provides the specified head geometry for this type of assembly. Selection of the bolt must be coordinated with the flange design, gasket, mating nuts and installation procedure rather than based only on nominal thread size.
For an accurate quotation, specify the thread size, nominal length, material requirement and surface finish, together with the intended mating component. Dimensions, inspection requirements and the exact material and finish combination must be agreed before order confirmation.
Key Features
- Heavy hexagon head
- Defined Grade B specification
- Inch-series procurement
Specifications
- Standard
- ASTM A307-21, Grade B
- Grade
- ASTM A307 Grade B; supply and documentation to confirm
- Diameter
- Specify nominal diameter in RFQ
- Length
- Specify nominal length in RFQ
- Head type
- Heavy hexagon
- Drive type
- External hexagon
- Thread type
- Inch thread; series and tolerance to be specified
Materials & Finishes
- Material
- Carbon steel to the ordered A307 Grade B requirement; supply unconfirmed
- Finish
- Subject to material, service conditions and specification
Typical Applications
- Cast-iron flange joints
- Specified piping connections
- Plant maintenance
Size Range / Technical Notes
- Size Range
- Specify inch diameter, thread series and under-head length. Do not convert a metric size into an assumed equivalent. Exact size and material combinations require confirmation.
- Technical Notes
- Grade B is not an ASTM F3125 structural bolt. Confirm the required material documentation, heavy-hex dimensions, nut selection and coating against the ordered specification.
Packaging & Customization
- Packing
- Packing method and pack quantity to be agreed
- MOQ
- Subject to specification/size and order quantity
- Customization Notes
- Submit drawings, finish requirements and packaging or marking requests for feasibility review. Custom production and OEM support require separate confirmation.