Girth Gear And Pinion Alignment

there is a hand tool available to recut key ways. it's called a key way broach. you may be able to recut the key way without removing the pinion. eHow has a good artical.

You had better get a consultant in, you don't seem to know what you're doing.

On the surface this sounds like a basic mechanical assembly procedure that should be easy enough to perform by a competent technician with the correct tools.

Ensure that the shaft is properly aligned using a straight edge and a square (or protractor if it is not designed to engage at other than 0 or 90 deg) A set of feeler gauges and shims will get the correct lash per spec.

That's my guess without any photos or other data.

Big question here is why the keyway on your shaft got damaged in the first instance. You will be replacing the clevis key too, yes?

you probably having situation where the teeth on pinion are now too sharp like double sided sharp edge knife, you better replace both shaft and pinion since the key is damage,there's a play between shaft and pinion,the shaft move first and then the pinion.too much back lashes that will impact on your kiln thrusting.

Thats a big job that will take min 36hrs down, shaft size is about 250-300mm+-50mm key i once done this job, so if you replace both you shouldn't have alignment issues in fact that type of system is a fixed system, what introduces alignment issues is wear and bearing issues.

now you'll replace the key, a month later you'll have to do the same amount of work to replace the pinion.

heating process is required to remove and install the pinion, don't know how do you intend to execute this job but i'll suggest you removed the unit complete and execute the task in the work shop, due to space and other safety dynamics involved.

good luck.

be Engineer,not Manager-don't make promises that you don't know how to keep.

Thank you very much for your reply.

As you explained we had already taken out the pinion assembly and sent to workshop for machining new shaft and key on which the old pinion has to be fixed after machining the bore slightly . Now there is two question arised

1. what is the fits and tolerance of pinion and shaft with double key(existing) . This is required for machining new shaft.

2 Please suggest me the points to be taken care during alignment of Girth gear and pinion .

i have already gave you an answer, heating process need to take place, so that means "Shrink fit/tight fit" so the shaft is slightly bigger than the bore of the pinion.that the reason why it needs to be heated. machinist will know that from the size of the shaft.

then your double key idea, you need to understand that key way are stress risers, the shaft will be subjected to twice the amount of stress than it would have been in single key way, that the reason why modern design moved away from double keys.

same effect apply to the pinion, key way is stress riser, and minimising your cross sectional area of you pinion and its becomes a coupling?

Ask yourself this: does the pinion transimit power or does it transmit torque?

first- have you calculated the maximin torque that the weakess part of the kiln can withstand? the double key ways concerns me. i believe that you added a second key way to prevent key way failure in the future. if that's the case, you are going to run into major problems. key ways are designed to carry a specified amount of torque plus other factor that apply specific to that piece of machinery.

!! START THERE! !! drop us a line afterwards. someone will give you the correct pinion/gear lash clearance.

it's pointless to give you anymore information until the primary problem has been corrected.