At High Speed Technologies, Inc. we repair Mori Seiki Spindles to original factory performance with a full warranty. We have 26 years of experience repairing spindles.
Known for manufacturing high end / high speed machining centers, Mori Seiki has delivered over 180,000 machines worldwide since their founding in 1948. With their main office located in Nagoya City Japan they provide first class CNC equipment worldwide. At HST we provide first class repairs on Mori Seiki spindles. Our work on Mori Seiki spindles ranges from basic rebuilds to major repair of fractured shafts. Mori spindles are rather nuanced. With our years of experience we are familiar with all of their little tricks.
Most Mories are oil injection or oil mist and run very fast. Mori spindles that are oil mist deliver lubrication to the bearings through small orifices in the spacers. Oil injection spindles deliver the lubrication through individual jets. At HST we take extraordinary care cleaning and refitting the oil lubrication jets. Each jet has a specific orifice diameter designed to meter the correct amount of oil to the bearing. The jets are a designed to an exact length that aligns the orifice at the optimum spot on the bearings. It is imperative that each jet is installed in the proper place.
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| Removing an oil jet from a Mori Seiki MH-63 spindle. The jets must be removed before break down. |
Oil jets have different lengths so they must be installed in the proper location. |
On some Mori Seiki Spindles, slots in the inner housing line up with holes in the outer spacer to provide oil mist |
Small orifices direct lubricant to bearings |
Oil lubricated spindles are a little less susceptible to outside contamination. However, it is critical to use high quality super clean lubricants. Old lube lines may in time be a source of contamination. At HST we provide new lube lines with every repair and we replace fittings as need be.
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| Old lubrication lines may be a source of contamination. |
This Mori Seiki MH-63 has new color coded lube lines: Standar procedure at HST. |
Even oil lubricated spindles are subject to contamination and sludge build up as seen in the bearing stack from a Mori Seiki NH-6300 |
Sludge and contamination build up on spacer |
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| Dye penetrant reveals multiple hairline cracks on this Big Plus Taper. | Cracks are micro welded | Taper is ground to Big Plus specs. This NH-4000 Spindle is still in operation. |
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Our customer crashed this NH-4000 Mori Seiki hard enough to crack the shaft. The dye penetrant reveals several hair line cracks. A new shaft was not only very expensive; it was a very long lead item. With a critical production schedule our customer had a problem. At HST we make the customer’s problem our problem. We micro welded the cracks and re-ground the taper to the original Big Plus specification. This type of repair is not as strong as a new shaft. However, it is strong enough for most work and the spindle was back up and cranking out parts in less than 1/5 of the time to get a new shaft. When time and budget permit HST has fabricated completely new shafts for a variety of spindle makes.
Crashes are the fastest way to end a spindles life as well as inflict other machine damage. Click on our Free Software tab to find out more about our Software Offer that will help reduce the possibility of a crash.
This Mori Seiki MH-63 (below) was crashed hard enough to wipeout one of the drive dogs. After a comprehensive examination and dye penetration testing it was determined that all other aspects of the shaft were within serviceable limits. Our customer requested that we retrofit the shaft with removable drive dogs.
The hardening on these shafts is very deep (and very hard). The shaft was salvaged and our customer is happy.
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| A Mori Seiki MH-63 spindle shaft modified to accept removable drive dogs |
The MH-63 retrofitted spindle shaft in our run-up station with a tool holder. |
Some Mories use small poppet valves (below) on the spindle face to control tool coolant. These need to be carefully examined and cleaned and sometimes replaced.
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| Good poppet | Bad poppet |
At High Speed Technologies we know ins and outs of Mori Seiki spindle repair.
Some of the Morie spindles are not cartridge type like this NH-6300 (right). This limits the maximum speed that we can run up to on our test stands. It also requires that a skilled technician installs the spindle. Although we will provide a new rear roller bearing properly fitted on the shaft, the on-site technician will be responsible for proper installation into the machine.
Mori Seiki enjoys a reputation as a high end CNC machine manufacturer. HST enjoys a reputation for repairing the spindles that go into those fine machines.