MAINTENANCE 4.12 EVERY 1000 OPERATING HOURS OR EVERY 6 MONTH High-Strength Bolt Connections (continued) Excavators with Electric Prime Mover Check condition and fastening of slip ring unit (01), illust. Z 20616 Reference No.: Qty. ((04) 4 (05) 4 (07) 4 405 Bolt size mm Grade SW * mm Tightening torque Nm M16 10.9 24 265 M16 8.8 24 180 M16 8.8 24 180