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Flange Head Screw & Bolts

Standards: DIN 6921

Diameter: 6mm to 16mm

Length: 10mm to 50mm

Grades: 8.8, 10.9, A2, A4

Finish: Black, Zinc Blue, Hot dip, Decromate, Yellow Passivation

Hex Flange Screws (also called Flange Bolts) incorporate a large bearing face (flange) into a one piece head design. The large bearing area under the head of this design provides additional benefits for assemblies over standard hex head cap screws:

Large bearing area under the head distributes clamp load over a larger area to resist fatigue loads. Minimizes indentation of the head into the material being bolted together to prevent loosening. Increases the heads resistance to rotation to prevent loosening in high vibration applications. Eliminates the need for a flat washer.

Hex Flange Screws are commonly called Frame Bolts because of their popularity in the trucking industry for use on assembly of truck frame rails. Hex Flange Screws are also used on pipe flange applications because the larger bearing area under the head helps ensure that the gasket is uniformly compressed to eliminate leaks. Hex Flange Screw can be used in any assembly that is currently using a hex cap screw and washer to eliminate the washer.

Earnest Machine Products line of Hex Flange Screws are made to the dimensions specified in the Industrial Fasteners Institute standard IFI -111. The head is manufactured with a full trimmed hex to prevent wrench slipping and rounding of the hex during installation or removal. The bearing faces are smooth to ensure uniform torque tension performance and that maximum clamp loads are achieved.

Flange Head Screw & Bolts
Manufactured from carbon steel that has been case hardened to a depth of .003? to .012? with a:
Surface Hardness : R15N 79/86
Core Hardness : Rc 25/34. For Grade 5 , 8.8
Rc 33/39. For Grade 8, 10.9
Ultimate Tensile Strength : 120,000 psi min (equivalent to Grade 5, 8.8 )
150,000 psi min( equivalent to Grade 8,10.9)