17Drive SquareTo avoid internal damage (especially due to torque overload), the output drive square has been designed toshear first. This saves major internal damage and allows easy square removal. For drive square partnumbers see page 5.FIGURE 11 – Drive Square ReplacementTo replace drive square:1. Remove the air supply.2. Support tool in a horizontal position3. Remove the screw or spring pin, then remove drive square.If the square has sheared it may be necessary to use pliers to remove the broken parts4. Fit new drive square.5. Fit new screw and tighten between 4 N·m to 5 N·m (for PTM52) or 8 N·m to 9 N·m (for PTM72/92/119)or insert new spring pin.6. Connect air supply.TIP: If the drive square fails continually then seek advice from Norbar or a Norbar distributor.CalibrationTo maintain the Pneutorque® accuracy it is recommended the tool is recalibrated at least every 12 months.Contact Norbar or a Norbar distributor for more information.CleaningKeep the tool in a clean condition to aid safety. Do not use abrasives or solvent based cleaners.DisposalRecycling Considerations:Component MaterialHandle Aluminium case / Steel internalsGearbox (clockwise / counter-clockwise) Aluminium case / Steel internalsGearbox (52mm / 72mm) Steel with nickel plated case / Steel internalsReaction bar PTM-52 is steel / PTM-72 is aluminium