Self-Drilling Screws

The Hex Washer Head Self-Drilling Screw with EPDM Washer is designed for fast, one-step fastening into steel sheet, roofing panels, purlins and light steel structures. The specially hardened drill point drills, taps and fastens in a single operation without pre-drilling, which is the main reason roofing crews prefer it: one tool, one motion, and the panel is fixed and sealed at the same time. The drill bit and the tapping area are made of specially hardened metal, so the point stays sharp long enough to keep drilling clean holes even through thicker purlins, and the hex washer head accepts a socket or nut driver at high speed without slipping. The bonded EPDM sealing washer under the head is vulcanized to a galvanized steel cap. It stays elastic across a wide temperature range, seals the fixing hole against rain and dust, resists UV exposure and does not crack in winter cold - the properties that decide whether a roof stays dry for years. Screws are produced in carbon steel with zinc plating for general work or with Ruspert-type high-corrosion coating for coastal and industrial atmospheres [TBC]. Point styles are selected by steel thickness: a finer point for sheet below 2 mm, a longer drill flute for thicker sections [TBC]; tell us the total steel thickness you fix through and we will match the point. Every batch is checked for point sharpness, drill capacity, thread quality and coating thickness, and salt-spray and tightened-torque tests are carried out regularly. Common sizes are #8, #10, #12 and #14 with various lengths [TBC]; washer diameter and hex size can be matched to your panel profile. As a factory-direct manufacturer we accept OEM orders, print your logo on the packing, and welcome mixed containers together with other fasteners from our range. Installation practice protects both the screw and the roof: drive at moderate speed so the point cuts rather than burns, stop as soon as the washer is compressed about half its thickness, and never re-drive a screw that has spun out - move to the next hole. Wobbling or over-speed driving enlarges the hole and the seal is lost, so most roofing teams prefer a clutch-adjusted screw gun; we can recommend the torque setting for each size. For long-term corrosion protection, match the coating to the environment: standard zinc for dry interiors, Ruspert-type coating for coastal buildings, and stainless steel versions for aggressive atmospheres [TBC]. Because self-drilling screws are consumed in large quantities on site, packing matters as much as quality - we box by size and length with a waterproof liner, and mixed pallets of several sizes can be shipped in one container so the site always has the next length ready.