Fast clutch (balloon type) is fastened to D/Ws drum shaft falnged hub by means of 16 large size bolts and locked with locking wire. In one of our D/Ws 8 nos of these bolts sheared resulting in prolonged down time and hence this question
2007-02-18 22:34:23 · 4 answers · asked by sarma k 1 in Science & Mathematics ➔ Engineering
check alignment
check hole dia wrt the dia of bolt
check bolt material
2007-02-19 04:22:39 · answer #1 · answered by purimani2005 4 · 0⤊ 0⤋
In addition to bolt material and torque level, you may want to also verify (1) bolt diameters, (2) the spacing between the holes on both mating flanges, and (3) the torque sequence.
A small bolts' diameter may allow too much a backlash and stronger shock cuts.
It is harder to shear all bolts at the same time but easier to shear one or two at a time either when one of the two flange's hole spacing is uneven or when all of the bolts are not of the same diameter.
Poor torque sequence may result in severe over torque. For example, if you torque one bolt all the way to the spec’d torque which causes the mating to have a gap on the opposite side. Then as you subsequently torque the opposite bolt, a lever force-amplification action may over stress the first bolt.
2007-02-19 07:59:06 · answer #2 · answered by sciquest 4 · 1⤊ 0⤋
Get a metallurgical evaluation of the sheared bolt by submitting both pieces to the lab - could be stress corrosion cracking due to sulphur in the oil etc.
http://www.tcreng.com/services/failure-analysis-metallography-testing.shtml
2007-02-21 23:25:27 · answer #3 · answered by Anonymous · 0⤊ 0⤋
Bolt material not up to specification?
Bolts over-torqued?
2007-02-19 07:26:59 · answer #4 · answered by lawomicron 4 · 0⤊ 0⤋