The documents provided do not specify an exact service life for a welder roll head. However, they do provide some guidelines on when to consider maintenance or replacement. For example, when the minimum diameter of the weld roll or disc is reached, regrinding is not recommended, and it may not be possible to compensate for the difference in radius with the revolver tool and the upper roll head adjustment.

The minimum diameters of the different welding rolls are as follows:
42 mm welding roll: 40.5 mm
49 mm Welding roller 47,5 mm
54 mm Welding roller 52.5 mm
62 mm Welding roll 60,5 mm
90 mm Welding roll 88.5 mm
90 mm Welding disc 86 mm
120 mm Welding disc 115 mm
130 mm Welding roll 125 mm

Please note that these figures are indicative and that actual service life may vary depending on use, maintenance and specific equipment model. Always follow the manufacturer’s guidelines for maintenance and replacement.