- Joined
- Dec 10, 2008
- Messages
- 7,253
So after having a cam failure and getting sucked into reading way to much crap about oils, I decided if I wanted to know I better do some more testing.
I had a Timkin scar tester some years ago but never thought it gave me any good valuable info so I put something together to do some testing. It is basically a scar tester that uses a Norton follower instead of a Timkin roller. This gives me line contact instead of point contact so I can use a lot more speed and load without causing an instant scar like the Timkin tester did.
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After spending time learning what I needed to know to build a good wide range tester I now have the final version. Thanks to all who have contributed to make this possible.
It has been upgraded with a wider temperature range plus the ability to heat or cool the oil automatically.
It now has the ability to apply as much as 500 lbs pressure to the follower and uses a load cell to sense the pressure.
It now has a sensor for motor load to give a friction reading. The oil temp is no longer logged since it is controlled to a range between 220 and 230 F. for the first 30 minutes of the test and then between 320 and 330 for the final portion.
The cooling fan run time is logged to show how much heat is being made by friction.
If the cooling system is not able to keep up with the heat from friction then the cooling fan will stop cycling and stay on. The oil temp with then be displayed by the same trace that was showing the fan cycles.
There is also a temp pickup located in the end of the follower to sense the follower Stellite temperature. Follower temperature that is higher than the oil target temperature is a good indication of the heat being produced by friction.
The heating element brings the oil temp to 220 degrees. If friction raises the temp to 230 degrees then the cooling fan comes on and stays on until the temp drops back to 225 degrees. The on/off cycles are seen as a sawtooth pattern on the logs. Total cooling fan time is given as a percentage of test time to failure.
After 25 minutes the controller raises the temperature to 320 degrees and the load on the follower begins to increase. The test ends when a scar is made on the follower and data is collected at this point.
With the new test procedure there will only be one graph for each oil test. It will cover both a friction/heat test at 220 degrees and then a load test till failure at 320 degrees.
A complete list of results will be linked soon. Jim
_________________________________________
I had a Timkin scar tester some years ago but never thought it gave me any good valuable info so I put something together to do some testing. It is basically a scar tester that uses a Norton follower instead of a Timkin roller. This gives me line contact instead of point contact so I can use a lot more speed and load without causing an instant scar like the Timkin tester did.
______________________________________________________________________
After spending time learning what I needed to know to build a good wide range tester I now have the final version. Thanks to all who have contributed to make this possible.
It has been upgraded with a wider temperature range plus the ability to heat or cool the oil automatically.
It now has the ability to apply as much as 500 lbs pressure to the follower and uses a load cell to sense the pressure.
It now has a sensor for motor load to give a friction reading. The oil temp is no longer logged since it is controlled to a range between 220 and 230 F. for the first 30 minutes of the test and then between 320 and 330 for the final portion.
The cooling fan run time is logged to show how much heat is being made by friction.
If the cooling system is not able to keep up with the heat from friction then the cooling fan will stop cycling and stay on. The oil temp with then be displayed by the same trace that was showing the fan cycles.
There is also a temp pickup located in the end of the follower to sense the follower Stellite temperature. Follower temperature that is higher than the oil target temperature is a good indication of the heat being produced by friction.
The heating element brings the oil temp to 220 degrees. If friction raises the temp to 230 degrees then the cooling fan comes on and stays on until the temp drops back to 225 degrees. The on/off cycles are seen as a sawtooth pattern on the logs. Total cooling fan time is given as a percentage of test time to failure.
After 25 minutes the controller raises the temperature to 320 degrees and the load on the follower begins to increase. The test ends when a scar is made on the follower and data is collected at this point.
With the new test procedure there will only be one graph for each oil test. It will cover both a friction/heat test at 220 degrees and then a load test till failure at 320 degrees.
A complete list of results will be linked soon. Jim
_________________________________________
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