Shaft modification or manufactured new one
Shaft modification or manufactured new one
(OP)
Hello all,
I am dealing with a problem with a shaft, the story is, I have a shaft to replace a damaged shaft in a system but this is shorter by 300 mm that I am requiring, my question is Can I add a piece of 300 mm to the shaft(welded or mech. coupling), to complete the total required length or This could be a little dangerous and it is necessary to manufacture a new shaft.
The shaft specs are:
Material= carbon steel
OD= 600
thickness= 30mm
actual Length= 6400mm
final length including the 300mm=6700mm
RPM=1-5
Another info, this shaft is part of a RBC system in a sewage treatment plant.
Thanks in advance.
I am dealing with a problem with a shaft, the story is, I have a shaft to replace a damaged shaft in a system but this is shorter by 300 mm that I am requiring, my question is Can I add a piece of 300 mm to the shaft(welded or mech. coupling), to complete the total required length or This could be a little dangerous and it is necessary to manufacture a new shaft.
The shaft specs are:
Material= carbon steel
OD= 600
thickness= 30mm
actual Length= 6400mm
final length including the 300mm=6700mm
RPM=1-5
Another info, this shaft is part of a RBC system in a sewage treatment plant.
Thanks in advance.





RE: Shaft modification or manufactured new one
A drawing of the element and marking where the current failure occured would help with the determination if it is possible in your case
RE: Shaft modification or manufactured new one
RE: Shaft modification or manufactured new one
RE: Shaft modification or manufactured new one
CS weld - assuming a good weld prep of sufficient size with a competent welder, the joint is straightforward.
RE: Shaft modification or manufactured new one
Is your shaft heat treated? This make welding more complicated.
--
JHG
RE: Shaft modification or manufactured new one
I am thinking in use a shaft coupling or welding to join the 300 mm missing length and of course do the recalculation of the stresses and deflection.
But my question here is: Base in your experience you think that is good idea do this or is better a new shaft.
RE: Shaft modification or manufactured new one
RE: Shaft modification or manufactured new one
I presume that the center section is hollow?
Does the smaller shaft run full length? Or is it welded to the ends?
I would rather see you replace the entire stub end instead of splicing it.
If the smaller shaft runs full length them putting the splice inside of the shell would lessen the bending load on it.
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P.E. Metallurgy, Plymouth Tube
RE: Shaft modification or manufactured new one
Another problem is, if I do some modification in the shaft, this could affect the position of another equipment in the system.
I recommended to design and fabricated a new shaft and the new shaft will be with a hollow section and two smaller shaft at the ends to fit with the bearings. The shaft that we have in stock can be used like spare part for other system where this shaft can fit perfectly.
Thanks by your help and recommendations.