Why trapezoidal wire?
The trapezoidal shape refers to the profile of the wire before it is wound into a washer. Once the wire is wound the profile becomes parallel ie. the top and bottom faces become parallel and the inside and outside faces remain parallel. Wire that does not start off trapezoidal before winding will result in a spring washer with a wire section that does not have parallel sides as is shown in the second example.
| Trapezoidal Wire | ||
![]() |
![]() |
![]() |
| Trapezoidal wire section before winding | Wire section after winding | The bolt is clamped onto the whole face of the washer |
| Non-trapezoidal Wire | ||
![]() |
![]() |
![]() |
| Parallel wire section before winding | Wire profile of a spring washer that isn't made from trapezoidal wire | Once the bolt is tightened it is only in contact with the washer on the inner points |
Finishes available are black (oiled), zinc or long lasting hot dipped galvanised.
Download our complete trapezoidal wire washer catalogue here (70KB).