gearing installation and maintenance Flashcards
What does the gear term backlash refer to?
Arc clearance between mounted, mating gears
Tooth wear on worm wheel causes?
More backlash
Excess backlash can be an indicator that the gear teeth are
Wearing
What is a mating gear mesh pattern?
The shiny metallic surface that show up when one tooth drives another
A good mesh pattern between gears that are mated is indicated by?
A central tooth pattern not contacting on either edge.
What I’d tolerance stack up?
Slight errors in machining that add up to a sum total
Why would you number a gear in four locations with numbers stamped on the side of the gear?
To allow backlash and mesh pattern checks over 360° or at four locations to establish gear and shaft integrity
Damaged gear teeth may have to be hand worked to remove burrs and high spots, what tool cab you use to dress these damaged teeth?
Abrasive files
What I’d used for checking for gear teeth cracks?
NDT dye penetrant and developer.
Why is residual magnetism dangerous to rebuild gearboxes?
Magnetism attracts iron particles to wear surface
Why should oil pressure fed lube system’s found in gearboxes be checked?
Wear in the pump can reduce the flow of lubricant
Overhauled gearboxes should be fitted with magnetic drain plugs and:?
Visual oil sight glasses.
How are shaft mounted reducers fastened to the shafts they drive?
By key’s and set screws
Some shaft mounted reducers use a device to absorb torsion load shock, what device do gearbox manufactures use to do this?
Spring type torque arms.
How can you make slight speed ratios changes on shaft mounted speed reducer drives?
Change the motor drive sheave or reduce input sheave size.
