Towball wear gauge 50 mm

• Steel gauge for quick assessment of the degree of wear of a 50 mm diameter tension ball.
• Designed for Class A coupling balls (e.g. A50-X).
• According to Annex 5 of Regulation No. 55 of the UN/ECE Regulation, the prescribed diameter of the ball is 50 mm with a tolerance of h13 (+ 0 mm / - 0.39 mm), i.e. the new coupling ball has a prescribed diameter of 49.61 mm to 50.00 mm.
• For the static separation test of a new coupling head according to Annex 6 of Regulation No 55 of the ECE/UN/ECE, a ball with a diameter of 49,00 mm to 49,13 mm is considered as a worn ball.
• With this gauge it is easy to detect a ball worn excessively - below 49 mm diameter.
• If the ball is excessively worn, the connection is not secure even when using a new, unworn ball coupling.
• Most modern pulling ball couplings (coupling heads) are equipped with a wear rate indicator for the ball coupling. This indicator shows a worn joint if either the drawbar coupling or the drawball or both are worn. The gauge can be used to easily determine how worn the ball is and whether the coupling only or the ball (or just the ball) needs to be replaced if the coupling is worn.

Using the dipstick:

Place the dipstick through the large hole at the top of the ball, with the protrusions in the hole pointing forwards and backwards in the direction of the vehicle and the dipstick in a horizontal position. If the ball passes through the gauge hole, it is excessively worn. Gradually move the gauge out of the horizontal plane by up to +/- 25 degrees and rotate the protrusions by up to +/- 60 degrees relative to the direction of travel of the vehicle. If the ball passes through the gauge hole in any such position, the ball is excessively worn. If the ball does not pass the gauge during this measurement, its diameter is greater than 49 mm and it can still be used. We recommend checking the wear rate whenever the wear rate indicator on the drawbar coupling shows excessive wear on the ball joint. If the clutch is not equipped with a wear rate indicator, it is recommended to check the ball wear rate at regular intervals.