OEM repaired parts
KMT Precision Grinding has always focused on high quality and reliability on our grinding machines.
In this respect, the grinding spindle is one of the most critical components. UVA EU High Frequency Grinding spindles are specially designed for demanding bore and seat grinding operations where optimum precision at high production rates is expected. Because the grinding spindle is the heart of the machine, KMT recommends an OEM repair so that the UVA grinder will continue to deliver the same quality and productivity as when the machine was new.
When UVA spindles need service, they are sent to the same precision assembly shop at our factory in Sweden that originally built the spindle. Here, KMT’s spindle specialists have both the knowledge and the special equipment needed to return your UVA spindle to the same performance level as when it was new. The highlights of UVA spindle repair procedures are outlined below.
The bearings are most critical to the performance of our spindles. KMT purchases bearings in batches in order to control quality. Due to the extreme demands on UVA spindles, we have sometimes found that even bearings that meet the manufacturers’ strictest standards will fail prematurely in service. KMT tests all new and repaired spindles as described below to prevent such failures. If an excessive number of bearing fail these tests, the entire batch is rejected and returned to the manufacturer. The following procedure applies to bearing replacement, and other repairs to the spindle:
1. UVA spindles are equipped with ultra-precision or ABEC9 hybrid angular contact bearings.
2. The specified bearing preload is achieved by a spring pulling the inner bearing housing into the spindle.
3. Rotors are balanced separately to maximum 2mm/sec vibration level. If necessary, the rotors are balanced again to the same level when the spindle is assembled.
4. After spindle assembly, the nose run-out and taper is inspected with specially designed KMT gages and tooling.
UVA Standard Repair Process
1. Test run of the spindle prior to disassembly, if possible, to identify faults and conditions before the repair is started.
2. The spindle is completely disassembled, and all components inspected and measured to verify integrity.
3. All components that can be reused are thoroughly cleaned in multiple steps to assure they are in full compliance with UVA specifications.
4. The rotor is checked and repaired or replaced as needed, and then precision balanced.
5. All components that cannot be reused are replaced. (Note that, depending on the items requiring replacement, extra cost may apply.)
6. All electrical connections are checked and re-soldered as needed.
7. The spindle is carefully assembled to UVA protocol.
8. New bearings are assembled, and spindle made ready for testing.
9. An 8–hour test run is made under controlled conditions, and spindle performance criteria monitored. (Details of test are highlighted below)
10. The test results are verified to assure that all performance criteria are met. In the event of a failure of any test, the condition is corrected, and the test is re-run.
11. Upon completion of the 8-hour test, the spindle’s balance is rechecked and the nosecone is precision ground.
12. A final test is made before the spindle is shipped.
13. The completed spindle is then carefully packaged for shipment back to the customer.
14. Extra steps on specific models include:
a. GPC – disassembling and assembling of transmitters
b. VG – change of tubes
c. VG – test of water bushing
Parts Replaced in a Standard Repair
1. (2) Bearings
2. (1) End Nut
3. (1) Nipple
4. (1) Protection Nut
5. (1) Washed Copper 2631-1/8
6. Note that the cost for parts required beyond those provided in the standard repair will be quoted after the evaluation is completed
Testing of Spindle
1. The spindle is connected to electricity, oil mist and cooling device.
2. Accelerometer is attached to the spindle.
3. Spindle is started according to instruction found in UVA Service Manual.
4. After running at full speed, a harmonic analysis of the spindle vibration is recorded.
5. The spindle is run at full speed for (8) eight hours.
6. New harmonic analysis is recorded.
1. Our technicians will evaluate your spindle and you will be quoted for the suggested repairs. There is absolutely no need to commit to having repairs done. If you decide that the cost to repair your spindle is not justified, let us now, and we will simply return it to you at no additional charge other than the SEK3500 evaluation fee. Please note: this evaluation fee will be applied to any authorized repairs.
1. 3-4 Weeks after approval to proceed with repairs. Note that this delivery estimate is also subject to demand at the time repair authorization is received by KMT.
1. An exchange system is offered when you need to get a repaired spindle quickly into production.
2. Within one day we are able to send you an already repaired spindle from our store as long as you agree to return your broken one to us.
3. As long as it is a standard repair we have fixed cost for the exchange. If we have to exchange parts not included in the standard repair we will charge extra for those parts.
1. A spindle repaired at KMT has 6 months warranty from date of shipment, alt 1000 working hours (not to exceed one year).
2. Warranty applies to spindles used in the proper applications, employing original equipment, and which follow KMT procedures for start-up, operation, and maintenance.
3. The cost of freight and / or shipping charges for any parts supplied or returned under this warranty will be the responsibility of the customer.
Of course we are able to perform these high quality repairs on all other parts to our grinding machines e.g. on the chuck, the ejector, the hydraulic slide, electronic cards etc. Regardless of what parts you would like to repair you will get the same high quality and the same procedure on the repairs you send to us. Just get in touch with us and we will be able to help you with your repairs for your grinding machine.
If requested the customer can receive an estimated quote before
sending it for repair. The part to be repaired is sent to a KMT site.
The part is controlled and evaluated. A quote is sent to the customer
with a delivery time and price.
- Fast response to inquiries and orders
- Repairs performed by skilled personnel
- Original spare parts secure the correct functionality
- In many cases parts older the 35 years can be repaired
To send your repairs or goods to KMT Bromma UVA
Please send the goods to be repaired to the KMT plant in Lidköping: Delivery address
Do you have any questions please contact the KMT site you are sending your goods to by clicking “Contact KMT Grinding“.