Fletcher Moorland's Servo test facility.
Hilfe, unsere
Robot hat gescheitert!
Matt Fletcher, managing director of Fletcher Moorland Ltd. outlines a recent incident where they were able to help a German Aerospace company overcome a critical breakdown. Help, our robot has failed!
Most members are used to emergency service repairs, but Matt Fletcher, managing director of Fletcher Moorland Ltd. based in Stoke on Trent, recently took an urgent call from a German Aerospace company in Lower Saxony. They had a critical failure on a materials handling Fanuc robot used to unload a CNC machine. The failure had stopped a line that was producing components for Airbus. It was the first failure they had experienced with a Fanuc robot motor and as such, did not know where to have it repaired. Their local motor rewind company could not help them, and so the company began to search the internet for a repair company with very special skills. They found the Fletcher Moorland website, which gave them the confidence they needed to arrange for a taxi to take the motor as quickly as possible for repair in the UK.
This is where the amount of time Fletcher Moorland have spent on their web site has begun to pay off. The dot com website is flagged up in 6 languages: German, French,
Italian, Spanish, Japanese and naturally English. This means that the critical search words are found in all of these languages by the search engines, and the site is optimized to come close to the top of the searches for Servo Motor repairs. It is a truly international website for a company promoting itself internationally. However this is only the starting point, with only a few moments to retain a potential customer's attention.
The web site is particularly good at highlighting their skills on the repair of servo motors among many other services. The servo section incorporates a large number of videos of repairs being carried out and their testing systems. Certainly the "Fanuc 6 axis robot drive test bed" video is very impressive, and you can understand the German company having every confidence that Fletcher Moorland would be able to help them.
The repair was so urgent that the taxi and motor were dispatched immediately to England and the driver given the instruction to stay in the UK until the repair had been completed and then deliver the unit straight back. Such was their faith in the web site, that it was only then that the customer rang Fletcher Moorland to give them all the motor nameplate information and fault details!
The taxi drove through the night virtually non stop, a 608 mile trip, and arrived at the works early the next morning. Whilst the husband and wife team had a well deserved rest in the conference room, the motor was booked into the job tracking system and assessed by the servo repair engineers.
The supervisor from the servo workshop had assembled a service/repair kit for a Fanuc Model No. A06B-0502-B855 servo motor, which is a type that they have seen many times before. The kit included OEM spares such as a new brake disk, new bearings, new connectors and new seals.
The main fault with the motor was that the brake had been contaminated with grease and was not able to hold the robot arm in position. The motor was stripped down and the brake thoroughly cleaned to remove all grease contaminant. The face plates were checked for surface flatness, and the brake coil resistance was checked with a new brake disk being fitted to the brake assembly.
Meanwhile the stator was cleaned until a satisfactory IR reading was achieved, the unit was then Baker surge tested, varnished, and stoved. Mechanical checks were carried out on the rotor and end-shields, which found the non-drive-end bearing housing was out of tolerance. The machine shop took care of the boring and sleeving of the housing to bring it back to specification. The Fanuc pulsecoder was connected to the test rig for serial encoders and the data read, analysed and checked. This rig checks for correct commutation, count, alarm and error data. Once the servo engineers were satisfied that all the faults had been found and fixed, new bearings were fitted to the rotor, and the motor was re-assembled.
Matt Fletcher highlights how critical it is to be able to fully test servo motors after repair, without a full and final test it is impossible to know if any servo motor will work correctly after repair.
The servo motor was connected and coupled to their universal servo motor load test rig. Firstly the motor was run in both directions under no load to check for correct operation. Then full nameplate load was applied to the motor under test and the motor was run from zero to full speed. The servo engineers measure and record the current and torque constant across the entire speed range in both directions. This tests the motor at full power and means it will work correctly when installed back on the robot. Fletcher Moorland also perform a procedure to bed in the new brake disk, and then measure the holding and breakaway torque of the brake.
The test results for this motor were printed onto the final test sheet and compared to the Fanuc specification for that particular servo motor. After painting and packaging the motor, it was passed back to the German taxi couple for another 608 mile trip back to the customer.
Later on that night Matt Fletcher received an email thanking all concerned for the very quick turnround. The motor had been fitted back onto the robot, and the line was back in service again, enabling them to fulfill their order to Airbus.
With the very large investment in spares and test equipment for all makes of servo and spindle motors, Fletcher Moorland have often been able to take the crisis out of an emergency for customers internationally, with motors having arrived as hand baggage on a scheduled flight, private plane, and even by chartered helicopter.
www.fletchermoorland.com Fanuc: www.fanucrobotics.co.uk
The Fanuc Servo motor stripped and showing the surplus grease on the brake.
The Fanuc stator pack, also well greased!
Little did they know the motor was already on its way by taxi, time for another 600 mile journey back.AEMT Journal Volume 9 Issue 1The Complete Servo Motor Repair Service
What does the complete servo motor repair
service mean ?
Perform Run Test* Perform Dynamic Load Test*'' Perform Max Speed, Max Load Test* Document Load Test Results?'
Shaft Repair Keyway Repair* Rotor Balancing to G1.0
• Winding integrity Check*
• Rewinds to Class 'H' *
• 2 Year Guarantee on Rewinds
Overhaul Brakes
Check Brake Holding Toraue*
Check Breakaway Torque*
Bearing Replacement* Clean Motor Internals*
Check, Repair & Test Encoders*
Check, Repair & Test Serial Encoders*
Align Encoders* *
Check & Test R^olvers^
Align Resolvers .
Check. Repair & Test Comrrytation Sensors
Align Commutation Senses
Reset Encoder Memory
Are you getting all this from your current servo motor repair company ?
Fletcher Moorland
24 Hour Manned Workshops
Call 01782 411021 www.fletchermoorland.co.uk