NB/T 11219-2023
Basic technical conditions of small bulb tubular turbine generator (English Version)

Standard No.

NB/T 11219-2023

Language

Chinese, Available in English version

Release Date

2023

Published By

Professional Standard - Energy  CN  /  NB

Latest

NB/T 11219-2023

Introduction

Analysis of the core content of the standard

Technical dimensions	General requirements	Special working conditions requirements
Rated capacity	5-570kVA	Maximum capacity can be set (subject to agreement)
Cooling system	Closed forced circulation	Secondary circulating water needs to be softened
Seismic design	Meet GB 50260	Seismic acceleration value needs to be provided

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Key technical indicators

Temperature rise limit: The B-class insulation resistance limit of the stator winding is 80K, and the F-class insulation is 100K (Table 1). Bearing temperature requirements: Thrust bearing Babbitt alloy bearing ≤75℃, plastic bearing ≤55℃.

Insulation performance: The insulation resistance of the stator winding at 100℃ is ≥(UN/(1000+SN/100))MΩ, and the polarization index is ≥2.0 (Clause 8.1-8.4).

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Key points of structural innovation

• Bulb body seal: Double sealing ring design + leakage detection groove (10.1.1/10.2.4)
• Rotor bracket: Stress at runaway speed does not exceed 20% of yield strength (10.3.2)
• Bearing system: High-pressure oil jacking device + dual backup oil pumps (10.4.1/10.5.4)

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Implementation suggestions

1. Installation acceptance: Axis adjustment must ensure that the stator and rotor air gap deviation is ≤±8% (9.7)
2. Trial operation: A 30-day assessment period is required after 72 hours of continuous operation (20.3-20.5)
3. Maintenance focus: Regularly check the status of the pole coil cooling fins (10.3.4)

NB/T 11219-2023 Referenced Document

• GB 50260 Code for seismic design of electrical installations
• GB/T 10069.1 Measurement of airborne noise emitted by rotating electrical machines and the noise limits Part 1: Method for the measurement of airborne noise emitted by rotating electrical machines
• GB/T 1029 Test procedures for three-phase synchronous machines
• GB/T 156 Standard voltages
• GB/T 2900.25 Electrotechnical terminology.Rotating electrical machines
• GB/T 32584 Evaluation of mechanical vibration for machine sets in hydraulic power plants and pump-storage plants
• GB/T 4942 Degrees of protection provided by the integral design of rotating electrical machines (IP code)—Classification
• GB/T 755 Rotating Machinery - Ratings and Performance*， 2025-08-01 Update
• GB/T 8564 Technical Specifications for Installation of Hydrogenerator Sets*， 2023-11-27 Update
• JB/T 6204 Specifications for withstand voltage test on stator coil and winding insulation of high voltage AC machines
• NB/T 42126 General technical conditions for small hydropower units
• SL 774 Technical conditions of small hydrogenerator excitation system

NB/T 11219-2023 history

• 2023 NB/T 11219-2023 Basic technical conditions of small bulb tubular turbine generator

Standard and Specification