Hexskruvar

Hexskruvar are a class of fasteners designed to be driven by a hexagonal tool interface. They include screws with a hexagonal recess in the head, known as socket head screws or socket cap screws, which are driven with an Allen key, and screws with a hexagonal head that accepts a standard wrench or socket. In practice the term covers both internal-drive and external-drive variants, though in some languages one subtype is referred to separately.

Common standards for hexskruvar are based on ISO metric threads or DIN specifications. Threads typically range from M3 to M24 with coarse or fine pitch. Socket head cap screws are often specified by DIN 912 or ISO 10642, and hex bolts by DIN 933 or ISO 4014/4017. Materials include carbon steel, alloy steel, and stainless steel, with coatings such as zinc plating, black oxide, or nickel for corrosion resistance. Strength classes for carbon steel variants commonly include 8.8 and 10.9; stainless types are rated by corrosion resistance (e.g., A2-70, A4-80 in ISO 3506).

Design and usage: the driving interface determines tools: an internal hex socket uses an Allen key, while a hex head requires an open-end, box-end, or socket wrench. Torque and preload depend on size, thread pitch, material, lubrication, and coating. Proper selection balances load, vibration, and environmental exposure.

Applications: hexskruvar are widely used in machinery, automotive assemblies, construction, electronics enclosures, and furniture, where reliable high-torque joints are needed in compact form.

See also: thread standards, DIN and ISO specifications, fastener materials and coatings.