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Machine brand
Doosan Spindle Repair and Rebuild
We repair and rebuild spindles from Doosan machines at our own workshop in Sankt Augustin, Germany. Turning headstocks, built-in motor spindles and machining centre units are stripped, measured and reassembled here. You can ship a spindle to us directly. On-site work is possible by prior technical arrangement. We are an independent repair workshop, not a Doosan dealer and not authorised by the manufacturer.
Scope
Doosan spindle systems we work on
Doosan Machine Tools was renamed DN Solutions, so the same spindle can arrive labelled either way. Most units reaching us are lathe headstocks rather than milling heads, and that changes the work: a large bar-capacity through-bore leaves a slim shaft section, and the bearing set at the nose carries chucking and draw-tube load as well as cutting load. Preload and bore geometry are measured against that, not against a generic figure.
Belt-driven turning spindles
The classic Doosan lathe headstock: a cartridge or housing-mounted shaft driven by poly-V belts from a separate motor. Belt tension pulls the rear bearings sideways, so wear rarely sits evenly. We strip the head, check the housing bores, and set preload for the bearing arrangement actually fitted.
Built-in motor turning spindles
Higher-specification Puma models carry the rotor directly on the spindle shaft. A winding fault, a bearing fault and a cooling problem present almost identically from outside, so the unit is stripped completely and the stator tested before anything is ordered. Rewinding is done where the stator is the fault; otherwise it stays.
Live tooling and milling units
Turn-mill machines carry driven tool units in the turret and, on some models, a separate B-axis milling spindle. These are small, run at high speed, and see coolant constantly. Bearings, seals and the drive coupling are the usual work, with the turret interface checked for backlash while the unit is out.
Machining centre spindles
Units reaching us usually come from DNM and NHP machines, in belt-driven, direct-drive and geared forms with BT40 or BT50 tooling. Work covers bearing replacement, taper regrinding and the drawbar stack. Where a gear range is fitted, the gears and shift mechanism are inspected before the head goes back together.
The exact configuration depends on the machine model and the year of manufacture. Two machines with the same model designation can carry different spindle units, so we confirm the build from your nameplate photograph before quoting.
Symptoms
Faults we see most often on Doosan spindles
Noise and rising vibration
On lathe headstocks the first sign is usually a change in finish on long turned parts rather than audible noise. We measure runout and bearing condition before deciding what comes out.
Overheating and thermal drift
Built-in motor spindles run hot when the cooling circuit silts up or preload has climbed. We check the jacket, the temperature sensor and the bearing set, and report which of them is actually driving the drift.
Runout at the taper
Chuck mounting faces and spindle noses take knocks during setup. The nose or taper is reground and runout corrected; if the shaft is bent, we say so before money goes into the rest.
Tool clamping problems
On turning heads this is normally the draw tube and rear cylinder rather than a drawbar. On machining centre spindles the disc spring stack and gripper are measured and the clamping force checked.
Encoder and orientation faults
C-axis and spindle orientation depend on the encoder and its coupling. A slipping ring or contaminated disc reads as a control fault; we test the sensor mechanically before anyone replaces a drive.
Coolant or grease ingress
Turning spindles sit in a wet zone and the front labyrinth is the only barrier. Emulsion in the front bearing is common; seals, slinger and the air purge line are all checked on reassembly.
Process
What a repair looks like
The spindle is logged in and inspected on arrival, then dismantled completely. We measure shaft and housing geometry, check the bearing seats, inspect windings and encoder, and photograph what we find. You receive a written quotation with the scope of work before anything is repaired. After the work is done the unit is dynamically balanced, run-in tested and shipped with a test report containing the measured values.
The individual operations — bearing replacement, rotor and stator rewinding, taper regrinding, drawbar and clamping repair, encoder work, seal and cooling circuit overhaul — are described on the services section of our homepage. On a Doosan spindle they are usually combined into one rebuild rather than ordered separately.
What to send with your enquiry
- Photographs of the spindle nameplate and of the tool interface
- Machine model, spindle type and year of manufacture
- A short description of the symptoms and when they appear
- Any measurements you already have — runout, temperature, vibration, current draw
- Whether the machine is still assembled or the spindle is already removed
Removal should be carried out by qualified personnel following the machine documentation. If that is not possible on site, ask us about removal and refitting as part of an on-site visit.
Shipping and on-site service
Our workshop is in Germany and we have no branch, warehouse or permanent staff in other countries. Customers outside Germany send the spindle to us by freight forwarder; we inspect, repair, test and return it. On-site work — removal, installation, alignment and commissioning — is possible internationally, but only after the job has been agreed technically in advance, so that the right parts and instruments travel with the technician.
Questions
Doosan spindle repair — frequently asked
Yes. We are an independent workshop, so a spindle can be sent to us directly by the machine owner or by a maintenance contractor. There is no dealer in the middle and we are not tied to one parts catalogue. What we cannot offer is any form of Doosan or DN Solutions authorisation. We have none, and we say so plainly.
Units reaching us usually come from Puma and Lynx lathes, from Puma MX and SMX turn-mill machines, and from DNM and NHP machining centres. Some arrive labelled DN Solutions after the company was renamed. That is a description of what we see, not a compatibility list; the work is decided from the spindle in front of us.
In most cases, yes. The stator is tested first, because a burnt winding and a seized bearing can produce the same symptom on the drive. If the winding is the fault, it is rewound and the stator re-impregnated; if it is sound, it stays in place and the work is mechanical. Which of the two applies is only clear after teardown.
Typically 5 to 10 working days from arrival, depending on parts availability and what the teardown reveals. That is an estimate, not a committed date; a binding date is only valid if confirmed in writing. Large turning heads with a rewind or a reground nose sit at the longer end, since machining and curing both take time.
The spindle is stripped, measured and assessed, and you receive a written quotation before any repair work starts. The assessment itself is chargeable and the amount is stated up front, so there is no surprise on the invoice. If you decide against the repair, the parts are returned or scrapped as you instruct.
Send us the spindle details
Tell us the machine model, the spindle type and what the machine is doing wrong. We come back with an initial assessment and a written quote before any work begins.