A rule of thumb is good, but checking is better.
When it comes to leak-free connections on hydraulic tubes, precision is required and reliable assembly is a crucial aspect. The risk of excessive or insufficient assembly due to inaccurate tightening angles is often pointed out in this respect. The issue of checking assembly tools is not talked about as much, but is equally important. A wear check on the assembly stud during the final assembly of 24° cutting ring fittings after 50 assembly processes, for example, is even stipulated in DIN 3859-2.
To exclude incorrect assembly, STAUFF recommends checking the 24° inner taper of the assembly stud with cone-gauges. This allows users to precisely determine the accurate dimension with precision and to also identify minimal deviations faster than during a visual check.
Another advantage: Regular checks mean that parts do not have to be replaced as a precautionary measure, saving unnecessary costs. In particular for large quantities, it is worth conducting a precise check for wear instead of relying on rules of thumb and visual checks. One note: Regularly oiling the assembly stud protects the material.
The cone-gauges can be purchased individually for tube diameters between 6 and 42 mm or as a set in a convenient case (FI box cone-gauge set 6-42). The cone-gauges are suitable for all final assembly studs of type FI-FK for manual final assembly and FI-MFK for final assembly with the cutting ring assembly machine.