Selection requirements for hotel elevator traction machines and guide rails

Selection requirements for hotel elevator traction machines and guide rails

I am elevator expert Ethan Liu. As the core drive and guidance components of an elevator system, the selection of the traction machine and guide rails directly affects the elevator's load capacity, ride smoothness, energy efficiency and long-term safety. In hotel projects, due to high passenger flow, frequent operation and extremely high comfort requirements, selection must comply with standards such as GB7588-2003 "Safety Rules for the Construction and Installation of Electric Lifts" and GB/T 10060-2011 "Code for Acceptance of Electric Lifts Installation," while also being optimized for the specific needs of hotel operation (e.g., low noise, high leveling accuracy, energy saving). The following is a detailed analysis based on years of engineering experience.

1. Traction Machine Selection Requirements

• Type Selection: For hotels, permanent magnet synchronous (PM) traction machines are recommended as the priority. Compared with asynchronous motors, PM machines offer advantages such as small size, high efficiency (up to above 90%), low noise (typically <55dB) and no machine room requirement, meeting the hotel's requirements for space utilization and a quiet environment. Clause 9.3 of GB7588 requires the traction machine to have sufficient drive capability; PM machines reduce gearbox losses through direct drive and improve response speed.
• Rated Load and Speed Matching: Based on hotel elevator load (commonly 800-1600kg) and speed (1.0-2.5m/s), the rated torque of the traction machine must cover full-load starting, acceleration and braking conditions. For example, for a passenger elevator with a load of 1000kg and a speed of 1.75m/s, the traction machine torque must be ≥500N·m, with a 10%-15% margin reserved to handle peak loads. Clause 9.3.1 of GB7588 requires the traction machine to start reliably at 125% of rated load.
• Braking System: Hotel elevators must use dual brakes (e.g., disc or drum type) to ensure redundant safety. Clause 9.10 of GB7588 requires the brakes to act independently, with a braking torque of at least 1.5 times the rated load. In an actual case, a five-star hotel selected a traction machine with a single brake, creating a risk of brake failure; it only passed acceptance after being replaced with a dual-brake model.
• Energy Efficiency and Heat Dissipation: Hotel elevators operate frequently every day (e.g., 200-300 times/day), so the traction machine must meet IE3 or higher energy efficiency class and be equipped with forced air cooling or water cooling to prevent overheating from overload. GB/T 24478-2009 "Traction Machines for Electric Lifts" requires a temperature rise limit of ≤70K (Class B insulation).

2. Guide Rail Selection Requirements

• Model and Stiffness: According to Clause 10.1 of GB7588, the guide rail cross-section dimensions must be determined by calculation, commonly using T-shaped guide rails (e.g., T89, T127, T140). For hotel passenger elevators (speed ≤2.5m/s), T127-B (cross-section 127mm×89mm) is recommended, with a bending section modulus ≥20cm³, capable of withstanding lateral forces from the car. Case: A hotel selected T89 guide rails, causing car sway during high-speed operation; the problem was only resolved after upgrading to T127.
• Material and Surface Treatment: Guide rail material should be Q235B or higher-strength steel, with surface roughness Ra≤3.2μm, and galvanized or coated with anti-rust paint (hotel environments have high humidity). Clause 5.3.2 of GB/T 10060 requires the straightness error after guide rail installation to be ≤1/1000, and the gap at joints to be ≤0.5mm; otherwise vibration and noise will occur.
• Installation Spacing: Guide rail bracket spacing must be ≤2.5m (Clause 10.1.2 of GB7588). Hotel hoistways are often concrete structures, requiring embedded steel plates or expansion bolt fixing. Case: A hotel had bracket spacing that was too large (3m), causing guide rail deformation at full load and leveling accuracy exceeding the limit (>±10mm); it only met the requirements of Clause 5.3.3 of GB/T 10060 after additional brackets were installed.
• Lubrication and Maintenance: Hotel guide rails should use self-lubricating types (e.g., oil-impregnated nylon guide shoes) to reduce friction noise. Clause 10.3 of GB7588 requires the guide rail surface to be regularly oiled, but hotel environments must avoid oil dripping, so dry lubrication systems are recommended.

Actual Engineering Cases

• Case 1 (Traction Machine): An international hotel chain (300 guest rooms) selected a permanent magnet synchronous traction machine with a load of 1250kg and a speed of 2.0m/s. During acceptance, the full-load starting current was found to be high (>120% of rated value); inspection showed the traction machine torque was undersized (only 450N·m). We recalculated according to Clause 9.3.1 of GB7588, increased the torque to 550N·m and replaced the model; subsequent operation was smooth and energy efficiency improved by 15%.
• Case 2 (Guide Rails): A high-end hotel (40 floors) used T140-B guide rails, but after installation the car exhibited lateral vibration during high-speed operation (2.5m/s). Testing showed the gap at guide rail joints reached 1.2mm (>the 0.5mm standard), and the bracket spacing was 3m. We readjusted the joints according to Clause 5.3.2 of GB/T 10060 and increased bracket density to 2m; the vibration peak dropped from 0.15m/s² to 0.05m/s², meeting the hotel's comfort requirements.

Concluding Summary

The above are reference opinions. The actual project situation still needs further comprehensive evaluation and implementation in combination with specific operating conditions, site conditions and other factors.