Flat head countersunk Allen bolt
Flat head countersunk Allen bolts are manufactured from carbon steel, alloy steel, or stainless steel and are specifically designed to sit flush with the surface of the workpiece. The countersink angle is typically 90 or 82 degrees, with diameters ranging from 3 to 20 millimeters and lengths from 8 to 120 millimeters. These bolts are produced according to DIN 7991 or ISO 10642 standards, ensuring flat geometry and full surface integration. Depending on the material, their tensile strength ranges from 500 to 1000 MPa, with common strength grades including 8.8, 10.9, or A2-70. They are tightened using an Allen key and are ideal for applications that require a smooth, flush surface without protrusions.
The thread of a flat head countersunk Allen bolt is typically metric, designed according to ISO standards with pitch values between 0.7 and 2.0 millimeters. Threads are available in both full and partial lengths, machined with a tolerance of ±0.15 millimeters. Surface finishes may include phosphate, galvanization, or polished stainless to improve corrosion resistance. Surface hardness ranges from 22 to 45 HRC for steel bolts and 200 to 400 Vickers for stainless versions. These bolts are used in aerospace, electronics, mold-making, and decorative fastening applications, allowing fo
