Low Profile Head Screw

 

There are many types of screw head shapes, including flat head, pan head, round head, hex head, countersunk head, and more. When purchasing screws, some customers may request screws with thinner heads, commonly referred to as low profile head screws.However, if used improperly, these low-profile head screws are prone to head breakage.

The cross recess of a screw is standardized, with a fixed width and depth. If the screw head is too thin and the head depth is less than the recess depth, the recess will extend into the screw shank, resulting in the issue shown in Figure 1. Once the screw recess extends into the shank, a void forms at the junction between the shank and the head, weakening the structural integrity of this area and increasing the likelihood of head breakage.

In contrast, for the same type of cross recess on a flat head screw with a normal head height range, after undergoing quenching and hardening treatment to enhance the screw's strength, as long as the customer's torque does not exceed the screw's rated torque value, the screw will not experience head breakage, as shown in Figure 2.

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Head height is consistently below 1.5 mm, saving space in equipment and devices or for use in areas with limited upper clearance.