Hardi COMMANDER 5500, Instruction Book

Page: 104 / 170

6 - Maintenance
102
Service and Maintenance Intervals
Tightening Bolts and Nuts
When tightening bolts and nuts as a part of periodic service or due to replacement of spare parts, it is important to apply
the correct torque. This will prevent accidents and prolong the lifetime of the parts included in the bolted joints.
If not otherwise stated in this book, please tighten bolts and nuts using the following torques.
*Exceeding this value results in a great risk of deforming the bolt.
±
WARNING! Applying too little torque will result in these risks:
±
WARNING! Exceeding the maximum torque will result in these risks:
Material: Surface treated steel Material: Stainless steel
Bolt size
(metric)
Recommended
torque
Maximum
torque*
Bolt size
(metric)
Recommended
torque
Maximum
torque*
M4 21 In/lb (2.4 Nm) 27 In/lb (3 Nm) M4 15 In/lb (1.7 Nm) 19 In/lb (2.1 Nm)
M5 44 In/lb (5 Nm) 53 In/lb (6 Nm) M5 31 In/lb (3.5 Nm) 37 In/lb (4.2 Nm)
M6 71 In/lb (8 Nm) 89 In/lb (10 Nm) M6 50 In/lb (5.6 Nm) 62 In/lb (7.0 Nm)
M8 15 Ft/lb (20 Nm) 18 Ft/lb (25 Nm) M8 124 In/lb (14 Nm) 155 In/lb (17.5 Nm)
M10 29 Ft/lb (39 Nm) 37 Ft/lb (50 Nm) M10 20 Ft/lb (27 Nm) 26 Ft/lb (35 Nm)
M12 52 Ft/lb (70 Nm) 63 Ft/lb (85 Nm) M12 36 Ft/lb (49 Nm) 44 Ft/lb (60 Nm)
M14 83 Ft/lb (112 Nm) 103 Ft/lb (140 Nm) M14 58 Ft/lb (78 Nm) 72 Ft/lb (98 Nm)
M16 133 Ft/lb (180 Nm) 159 Ft/lb (215 Nm) M16 93 Ft/lb (126 Nm) 111 Ft/lb (151 Nm)
M18 177 Ft/lb (240 Nm) 225 Ft/lb (305 Nm) M18 124 Ft/lb (168 Nm) 158 Ft/lb (214 Nm)
M20 258 Ft/lb (350 Nm) 321 Ft/ lb (435 Nm) M20 181 Ft/lb (245 Nm) 225 Ft/lb (305 Nm)
M22 361 Ft/lb (490 Nm) 435 Ft/lb (590 Nm) M22 253 Ft/lb (343 Nm) 305 Ft/lb (413 Nm)
M24 443 Ft/lb (600 Nm) 553 Ft/lb (750 Nm) M24 310 Ft/lb (420 Nm) 387 Ft/lb (525 Nm)
M27 720 Ft/ lb (976 Nm) 811 Ft/lb (1100 Nm) M27 504 Ft/lb (683 Nm) 568 Ft/lb (770 Nm)
M30 959 Ft/lb (1300 Nm) 1103 Ft/lb (1495 Nm) M30 671 Ft/lb (910 Nm) 772 Ft/lb (1047 Nm)
•
bolted joints will rattle and thus fail under fatigue
•
bolts are being worn quickly and thus will not fulfill their design purpose
•
bolted joints will come loose
•
accidents caused by assembled parts coming apart due to bolts or nuts failing or falling off.
•
damaging or stripping the threads and deforming the bolt
•
bolt heads will be broken
•
bolted joints will come loose
•
accidents caused by assembled parts coming apart due to bolts breaking at a later time.