To measure a stainless steel clevis for replacement, take seven dimensions from the old part, not just the pin diameter. They are inside width, pin-hole diameter, slot length, overall length, outside width, thread, and the thickness of the mating eye it closes around. Measure where the metal is still unworn, because a worn clevis misreports its own size.
Measure Where the Part Is Still Unworn
Wear opens the fork and stretches a pin hole into an oval, so a reading at the worn spot overstates the size. Measure the inside width at two or three heights along the slot, record the smallest value near the slot bottom and the largest at the opening, and give both when you ask for a quote.
The Seven Measurements to Take
| Measurement | What it is and how to take it | Common mistake |
|---|---|---|
| Inside width | The gap between the inner faces of the two ears. Caliper across them. | Reading it only at the worn opening |
| Pin-hole diameter | The bore through both ears. Pin gauge, or caliper jaws across the unworn side of the hole. | Using the pin's diameter instead of the hole's |
| Slot length | The depth of the opening, from the end of the ears to the bottom of the slot. | Confusing it with overall length |
| Overall length | From the end of the ears to the end of the threaded shank. | Measuring with the pin or lock nut fitted |
| Outside width | Across the outer faces of the two ears. | Skipping it when space around the joint is tight |
| Thread | Major diameter, pitch with a thread gauge, hand, internal or external, and shank thread length. | Assuming coarse pitch, since one size often comes in coarse and fine pitch |
| Mating eye thickness | The width of the eye or tab the fork closes around, plus any washers between eye and ears. | Using a nominal size instead of the real width |
If the part is a DIN 71752 size, its designation already carries two of these numbers. How to read a DIN 71752 size shows how to check yours against it.
What to Send With the Old Part
Profab checks the mating dimensions before quoting. Send photos of both ears and pin holes with a ruler in frame, plus:
- The seven measurements, with both readings where wear makes them differ
- Thread size, pitch, hand, and internal or external shank
- Retention method (cotter pin, R-clip or circlip) and pin diameter
- Grade if known, environment, and quantity
Conclusion
A replacement clevis fits when its inside width, pin hole, slot, thread and overall length match the old part and its mating eye, not just the pin. Measure the unworn areas and record both values where wear shows. If you are looking for a new supplier of stainless steel clevises, send the old part or these measurements to Profab Machine and we will match it or machine it to your drawing.