Posted by Martin Sunderland on July 06, 2001 at 09:10:51:
In Reply to: Gear Grinding: Single Tooth or Reishauer Type?? posted by Rob D. on January 08, 2001 at 13:47:45:
Grinding gears, preferably carburised or induction hardened, of Q10 can EASILY be accommodated on either Reishauer or a single tooth process machine (assuming modern well maintained machines)Quality is not the issue.
At Hindle Gears we operate 3 CNC, and manual Reishauers as well as single tooth process machines.
Some food for thought:
Grinding with a rack shaped wheel is generative ie will generate the profile as the the gear rotates and the rack shape as and rolls across the line of action. Reishauer RZ utilises the rack in the form of a single or multi-start worm, Niles,Hofler have the rack on a single disk wheel.
The full form grinding process by Kapp, Oerlikon etc, employs a single disk wheel with the involute form dressed on the wheel and produces both left and right flanks in 1 axial pass and no gear rotation.
The division is not so simple as "Reishauer vs single tooth grind"
The full form grinding process with a CBN wheel is highly productive, carries a high tool cost, is less flexible(1 tool per part no),low set up times, more prone to burning. The full form process with an SG type wheel is less productive, low tool cost, flexible(profile CNC dressed onto wheel), still prone to burning. The single tooth rack process with an SG wheel is less productive very flexible(profile modification CNC dressed onto wheel), low tooling cost, less prone to burn. The worm rack grinding process (Reishauer) is highly productive, longer setup times, high tooling costs, low risk of burning.
There will be many other influencing factors(capital cost!!).
Now becoming as clear as mud eh?
You need to look at what you want. What are the annual volumes, all current machines will gobble up work.
What range of work have you? large no of part nos or small? Do you need flexibility. What batch sizes do you have, 10 off or 1000 off will be affected by set up times. The list could go on.......
Just as a matter of interest a 16dp 42tooth gear 1" face could be ground on a Reishauer RZ362 in 1.25 mins with any profile or lead desired and Q11,12,13.
I would appreciate any feedback.