When a motor fails, production stops. At WAT Engineering we rebuild what others replace. From a 3 kW pump motor in a remote wadi to a 1 MW gas-compressor drive on a platform, our Muscat workshop rescues critical machines, extends their life and cuts your capital spend.
WHAT WE DO
- Complete motor rewinding – random-wound or form-coil, LV ≤ 3.3 kV
- In-situ machining – shaft spray-weld, journal build-up, bearing-seat re-cut
- Rotor repairs – bar replacement, shorting-ring weld, balance to ISO 1940 G2.5
- Mechanical overhaul – bearing change, alignment, coupling, cooling-fan, seal replacement
- High-vacuum VPI – Class F or H insulation systems, 100 % solids, no VOC
- Emergency response – 24 h strip-down, 48 h rewind, same-day bearing swap
- Condition testing – IR, PI, surge, Hi-Pot, vibration, thermography, core-loss
TYPICAL MOTOR TYPES
| Sector | Common ratings | Faults we solve |
|---|---|---|
| Oil & Gas | 15 kW – 1 MW | Salt ingress, overload burn, bearing seizure |
| Water & Waste | 7.5 – 450 kW | Locked rotor, moisture soak, shaft wear |
| Cement | 250 kW – 3.3 kV | Dust wash-down, cracked end-shield, core damage |
| Marine | 5 – 750 kW | Vibration, spray corrosion, reverse rotation |
| HVAC | 1 – 132 kW | Capacitor blow, noisy bearing, shorted turns |
REPAIR vs REPLACE – THE NUMBERS
- Average rewind cost: 30 – 45 % of new motor price
- Energy saving after precision rewind: ≤ 1 % additional loss (IEC 60034-23 limit)
- Extended life: 8 – 15 years when operated correctly
- CO₂ saving: ≈ 250 kg per 100 kg motor core kept in service
MATERIALS & PROCESS – “NO SHORT-CUTS”
- Conductor: 99.9 % IACS electrolytic copper, IEC 60317, size-matched for original current density
- Insulation: Aramid paper slot liners, Class H (180 °C) as minimum; Nomex®-type or equivalent on request
- Varnish: Solvent-less polyester-imide, vacuum-pressure impregnation 5 mbar / 2 bar, gel 160 °C, cure 180 °C
- Bearings: SKF Explorer or FAG X-Life, C3 clearance, lithium-complex grease 180 °C
- Shaft repair: 420 SS spray-weld, finish-ground to h6, chrome flash if marine duty
- Balance: Computerised Schenck hard-bearing machine, tolerance to ISO 1940 grade G2.5 at rated speed
- Final test: No-load vibration ≤ 1.8 mm/s RMS, starting current ± 5 % of OEM value
CAPABILITY AT A GLANCE
| Workshop, Muscat | On-Site Fleet |
|---|---|
| Lift capacity: 12 t overhead crane | Mobile lathe: Ø 600 mm × 2 500 mm |
| VPI tank: Ø 1 200 mm × 2 000 mm | In-situ balancing: 30 g to 5 000 kg rotor |
| Bake oven: 220 °C, 5 m long | Bearing induction heater: 100 kW |
| Test panel: 415 V – 3.3 kV, 200 kVA | Laser alignment kit: 0.001 mm resolution |
24/7 EMERGENCY PROCEDURE
- Hot-line +968 9XXX XXXX – failure details
- Technician dispatched within 2 h (Muscat) / 6 h (Interior)
- Quick diagnostics – strip report with photo log same shift
- Rewind or bearing swap on continuous shift until ready
- Motor returned, aligned, commissioned – full report handed over
PREVENTIVE PROGRAMMES
- Annual thermography – catch hot bearings before seizure
- Quarterly vibration trending – ISO 10816 limits, spectrum analysis
- Oil/debris analysis – detect bearing fatigue early
- Fixed-price rewind contract – budget locked, parts reserved
STANDARDS & CERTIFICATIONS
- IEC 60034-1, -18-21, -23 (rotating electrical machines – tests & rewinds)
- IEEE 43 (insulation resistance), IEEE 522 (surge comparison)
- API 541 / 547 (petro-chemical motors) on request
- Oman Environmental Permit for solvent-free VPI operation
WARRANTY – SIMPLE & CLEAR
We guarantee the rewound winding for 12 months from date of collection.
Not covered: bearings, mechanical damage, supply imbalance, overload, water ingress, unauthorised opening.
If the winding fails under normal load, we rewind once more free of charge – you only pay freight.
RECENT SUCCESSES
- BP Khazzan: 450 kW 3.3 kV booster pump motor – rotor bar replaced, rewound in 72 h, core-loss 25 % below OEM.
- Oman Water: 132 kW submersible – salt-water burn, new 220 °C insulation, back on-line 4 days vs 8-week import.
- OCC Cement: 800 kW kiln fan DC motor – armature rewound, commutator re-mica, vibration reduced 70 %.
