Torque Value

[Instnapp05]

Hi All,

I have a quick question where I need your help. I’m looking for torque values for case bolts for # 4 10900 actuator. Do you have a table or procedure?
I've reviewed the actuator manual for same and there is no such information related to torque values for actuator maintenance.
Appreciate the feedback.

Thanks
Naresh

 

[gerhardl]

Case bolts? Bolts to fasten actuator to spindle top? Thousands of variations exists, sizes of bolts, geometrical layout and forces. No 'general tables exists.

Generally all bolts should be fastened satisfactorily enough to give the required friction between the
top-plate of the spindle and the actuator footplate. The friction keeps the actuator positioned, not the bolts as such.

Torque? As other bolts: far less than the allowed maximum torque for the bolts themselves. If no data is given or will be given from the actuator producer, then you have a supplier hat is weak on the technical side, and have to compare to similar contraptions with similar bolt sizes and quality.

 

[niteshgargeck]

You can refer the standard torque values as per the bolt size moc n type of coating/finish.

 

[cranekiran]

Dear Naresh,

Bolt tightening torque = D*K*P

where D= dia of bolt = say 56mm with pitch 3mm, Core dia=52.15mm

P = Bolt tensile load = 0.75 * yield stress ( in N/mm2)* area ( which is 3.14*52.14sq/4)

consider yield stress as 900 N/mm2 ( for class 10.9)

Therefore P= 1442235 N

K = Plain finished bolts=0.2
Zinc plated bolts =0.22
Waxed or highly lubricated bolts =0.1

suppose we take k=0.1

Torque =8076518 N-mm= 823 kgf m

so you have the bolt torque as 823 kgf.

hope this helps.Bye cranekiran