Previous in Forum: High Pressured Gas Divertion   Next in Forum: Air Conditioning Heat Load Calculation
Close
Close
Close
4 comments
Rate Comments: Nested
Associate

Join Date: Oct 2006
Location: chennai, India
Posts: 29

Calculating Wear on Shifter Pad of Gearbox

03/25/2013 11:14 AM

I have a complaint of bnormal wear of 1mm to 2mm wear on steel pad(16MnCr5) with 60hrc. Th shifter sleeve is also 60hrc steel. I am trying to calculate the force which is required to start the wear of steel pad.

There is no burning marks and is well lubricated. Theoritically the sleeve undergoes a force only in synchronization which is about 520N on sleeve considering a knob force of 70N which is measured on knob.

PLease help me calculate the force required to wear a steel pad like this under well lubricated condition. This is a conventional 5 speed gearbox layout with 4th as dricet drive and wear is only on the 3rd side and not on 4th or any other gear.

__________________
sam
Register to Reply
Pathfinder Tags: wear calculation
Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.
Member

Join Date: Nov 2012
Location: Pooler GA.
Posts: 7
Good Answers: 1
#1

Re: Calculating Wear on Shifter Pad of Gearbox

03/25/2013 11:52 AM

If this is a vehicle transmission then either the shifter is maladjusted or the operator rests his/her hand on the shifter while in operation, check the end point stops of the shifter they are probably causing a coutinuous load due to the positive stop being too tight. As far as the calculation goes I would not concern myself with that. Repair the problem and the symtoms will go away.

__________________
"Never seem more learned than the people you are with. Wear your learning like a pocket watch and keep it hidden. Do not pull it out to count the hours, but give the time when you are asked".
Register to Reply
Guru

Join Date: Mar 2007
Location: City of Light
Posts: 3943
Good Answers: 183
#2

Re: Calculating Wear on Shifter Pad of Gearbox

03/25/2013 3:15 PM

Wear is directly related to the shear stress in the sliding zone. It is not enough to give the force all geometrical data must be available for an evaluation.

Could give more information and if possible picture of worn parts ?

The synchronization force should as well be checked if it is really in correct relation to the process (condition when commuting, dimensions and possible frictions aso).

Register to Reply
Guru
Hobbies - DIY Welding - New Member

Join Date: Sep 2007
Posts: 1601
Good Answers: 58
#3

Re: Calculating Wear on Shifter Pad of Gearbox

03/26/2013 9:02 AM

I have opened transmissions with >>200,000 miles on them and found no significant wear in that area. If you are achieving proper hydrodynamic lubrication between the moving parts, there should be zero wear. I suspect that either the lubricating oil is being wiped away during shifting and not available to maintain a film between the parts, or the transmissions are being dry shifted excessively. Perhaps to test this theory, you might want to install a small pump to force lubricate the sliding joint whenever shifting occurs.

Register to Reply
Guru
Popular Science - Weaponology - New Member Safety - ESD - New Member Hobbies - Fishing - New Member

Join Date: Sep 2006
Location: Near Frankfurt am Main, Germany. 50.390866N, 8.884827E
Posts: 17996
Good Answers: 200
#4
In reply to #3

Re: Calculating Wear on Shifter Pad of Gearbox

03/29/2013 2:29 PM

Possibly the wrong lubrication? Or one that is too cheap/not a true equivalent to the recommended?

__________________
"What others say about you reveals more about them, than it does you." Anon.
Register to Reply
Register to Reply 4 comments
Copy to Clipboard

Users who posted comments:

Andy Germany (1); mlindner (1); nick name (1); welderman (1)

Previous in Forum: High Pressured Gas Divertion   Next in Forum: Air Conditioning Heat Load Calculation

Advertisement