Description

1. Construction snapshot Stator: concentrated winding, 48 slots, H-class insulation (180 °C), Class F temperature rise (105 K). Rotor: 24-pole sintered NdFeB, 1.2 T remanence, stainless band retention rated 20 000 rpm burst. Bearing pair: sealed SKF 6314-2RS1, grease life 40 000 h at 75 °C. Encoder: 2 048-ppr sine-cosine, differential, with zero pulse aligned to pole #1. Brake: twin-disk DC 110 V, 2 × 690 N static, micro-switch verified, noise < 45 dB(A). Frame: cast iron GG-25, torsion-proof foot pattern 350 × 150 mm, mass 195 kg. Protection: IP41 stator, IP20 brake, optional IP54 cover (NY-COV-GTW9).
2. Pre-installation safety & rigging Lock-out main supply; verify car is on rail clamps at bottom landing. Use a 3 t beam clamp and certified 2 t polyester sling through the lifting eye (M20, torque 180 N·m). Rotate hand-wheel so brake faces down—this keeps brake discs horizontal and prevents disk slip during alignment. Keep magnet surfaces clear of ferrous debris; a single 3 mm nut can become a 200 kg projectile at 150 rpm.
3. Retrofit footprint check GTW9S replaces 450 mm-diameter geared machines without beam modification. Verify: Sheave centre 120 mm above old centre (use 10 mm shim plate supplied by Nanjing Zhuye). Rope groove pitch 10 / 12 mm; order correct groove count (5–6) to match existing ropes. Motor flange 300 mm from guide-rail face; < 250 mm causes hand-wheel clash with governor.
4. Alignment in 15 minutes a) Lower machine onto beam, hand-tighten four M20 bolts. b) String line from car to counter-weight sheave; lateral offset must be < 0.5 mm. c) Use 0.2 mm feeler between brake hub and string; adjust shim until parallel within 0.2 mm / m. d) Torque foot bolts 280 N·m in cross-pattern; re-check offset—beam compression often shifts machine 0.3 mm. e) Install anti-vibration pads (NY-AVP-GTW9, 6 mm SBR) under feet; this cuts structure-borne noise 4 dB(A).
5. Encoder & phasing Connect shielded pair to CN1; shield grounded at controller end only. Run auto-phasing: Set controller to “PM learn” mode. Rotate machine by hand-wheel 360°; controller records A/B zero offset. If offset drifts > ±2° between runs, encoder coupling is loose—replace elastic insert (NY-COU-14-14). Final polarity check: command 0.1 m/s up; if car creeps down, swap any two motor phases and re-learn.
6. Brake set-up Air gap factory-set 0.25 mm; check with feeler at three points. Gap > 0.4 mm causes 30 % torque loss and late-leveling faults. Adjust by turning hex nuts clockwise 1/6 turn = 0.05 mm. Micro-switch must click 0.5 mm before brake pads touch; verify with multimeter (continuity beep). After adjustment, run 20 full cycles; re-torque nuts—vibration settles the Belleville washers.
7. Lubrication & wear points Bearings are sealed-for-life SKF LGHP2 grease; no field re-lube required. However, grease life halves for every 15 °C rise. Predicted life: @ 70 °C housing (1.0 m/s, 300 trips/day) – 40 000 h ≈ 5.5 years. @ 55 °C housing (1.6 m/s, 600 trips/day with IP54 cover) – 80 000 h ≈ 11 years. Annual IR scan: bearing housing should be < 65 °C; > 75 °C schedules bearing change.
8. Magnet degradation & demagnetisation check NdFeB loses 1 % flux every 10 °C above 80 °C. Measure no-load back-EMF: Spin machine at 150 rpm by hand-wheel. Record line-to-line voltage; compare to nameplate ±5 %.

5 % drop indicates partial demag—order replacement rotor (NY-ROT-GTW9) or full machine.

9. Replacement cycle summary Light traffic (residence, 150 trips/day) – replace bearings ≈ 12 years, rotor ≈ 20 years, full machine ≈ 25 years. Medium traffic (office, 400 trips/day) – bearings every 8 years, rotor every 15 years, full machine every 20 years. Heavy traffic (mall/metro, 800 trips/day) – bearings every 5 years, rotor every 10 years, full machine every 15 years. Always replace encoder elastic insert and brake discs when bearings are changed—labor overlap saves 2 h.
10. Rapid swap strategy (downtime < 3 h) a) Secure car on clamps, lock-out power. b) Sling old machine, remove ropes, drop 195 kg to pallet. c) Offer new Nanjing Zhuye GTW9S, align with existing shim. d) Re-rope, tension, run encoder learn, brake gap check. e) Perform full-speed test with 125 % load; vibration < 1.5 mm/s RMS (ISO 18738). f) Log serial number, cycle counter and brake air gap; return old unit for core refund.
11. Sustainability & core return Nanjing Zhuye pays $150 core credit per GTW9S. Stator copper is remelted 99.9 % pure, rotor magnets re-sintered, steel frame reused for counter-weights. One recycled machine saves 1.1 t CO₂—equivalent to the elevator’s standby consumption for 3 months.