Machinery Alert on MAN Diesel & Turbo four-stroke L32/40CD and V32/40CD engines
MAN Diesel & Turbo has released Customer Information circular No.334 advising the maximum torque limit when using their scissor jack to remove main bearing caps on their four-stroke L32/40CD and V32/40CD engines.
The circular advises that when using the scissor jack to remove main bearing caps a 0 - 200 Nm torque wrench should always be used. The torque required to operate the jack should not exceed 130 Nm. If a torque in excess of 130 Nm is required, this indicates that something is wrong (for example, the main bearing cap is clamping).
Using a torque in excess of 130 Nm is likely to overload the scissor jack and increase the risk of an accident. Operators are advised to engrave scissor jacks with the wording "maximum permissible torque 130 Nm" to avoid inadvertently exceeding the limit.
Image Credit: MAN Customer Information Circular No.334
If the scissors jack has been used previously without the torque wrench, connecting bolts and the thread of thespindle must be checked. If there is a visible damage (deformation of bearing stress) on joints or spindle, thescissors jack should no longer be used.