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No. The reverse weld orientation creates different load paths. We can provide load-limit values and tightening torque recommendations on request to support correct application.

With reverse weld collar, the overall product length is the same as the collar length. This differs from standard collar products, where overall length includes both collar length and Head thickness. Screw engagement is approximately equal to the full collar length.

This customisation applies only to sighted internally threaded collar types (F2/SF2) and specific Head types including S20, S23, ST38A, S30, S32 and S38A, with defined thread‑size ranges for each.

Reverse weld collars are useful for applications where: Axial fastening loads or tensile stresses may exceed the weld strength of a standard collar, or You need to present a smooth, uninterrupted Head surface for component seating or moulding shut‑off.

It reorients the Head position, so that the collar shank passes through the sighted Head. The weld is applied to the flange on the shank side, instead of the Head being welded to the flange end.

No. ISO 4753 end-forms do not affect weld load limit (WLL), fixing load limit (FLL) or recommended tightening torque values.

FL is intended for screws that bear against a surface, and SD/LD are intended for screws that locate into holes or slots. Neither supports reliable nut engagement on a stud. These forms can look similar to CH, PF and PC. Because of this, we prefer to discuss your requirements before quoting to ensure the correct end-form for your application.

Choose PF (flat pilot shape) when you need enhanced nut lead‑in and reduced cross-threading, such as in automated or repeated manual assembly. Choose PC (tapered pilot shape) when you need greater self‑alignment for automated process integration or tighter positional tolerances.

CH improves nut lead-in and self-seating, reducing cross-threading during manual or semi-automated assembly. It does not increase the overall stud length.

Here is the body text for FAQ 3.