GB14681.2-2006
Electrically heated glazing materials for railway rolling stock and ship Part 2: Electrically heated glazing materials for railway rolling stock
机车船舶用电加温玻璃 第2部分：机车电加温玻璃
GB 14681.2-2006 is a current mandatory Chinese national standard for Electrically heated glazing materials for railway rolling stock and ship Part 2: Electrically heated glazing materials for railway rolling stock. It appears in the Electronics compliance cluster with a electrical safety focus and has an implementation date of Dec 1, 2006.
Applicability depends on product scope, certification route, competent authority notices and transition rules. Requst for the translation or verify source before using this record in a compliance decision.
Compliance overview
Scope and applicability
This standard specifies the technical requirements for electrically heated glazing materials used in the front windows of locomotives and electric multiple units (EMUs). It is applicable to both ordinary-speed (under 200 km/h) and high-speed (200 km/h and above) rail vehicles. It does not apply to electrically heated glazing for aircraft or ships, which are covered by separate standards. It may also be referenced for other parts of locomotives and automotive windshields.
Technical requirements
The standard outlines comprehensive technical specifications across several categories. For dimensional and geometric tolerances, it defines limits for outline dimensions, thickness deviations, mismatch (layer offset), and curvature for both flat (Type A) and curved (Type B) glass. Regarding optical performance, the standard mandates a minimum visible light transmittance of 70% and sets specific limits for optical distortion to ensure clear visibility. The environmental stability requirements include resistance to heat, radiation, and humidity, ensuring the laminated glass does not develop bubbles, delamination, or significant color changes under harsh conditions. For mechanical properties, the standard differentiates between train types: ordinary-speed glass must pass a penetration resistance test (steel ball drop), while high-speed glass must withstand a ballistic impact test where the impact velocity is calculated based on the locomotive's design speed. High-speed glass must prevent projectile penetration and remain secured in its frame after impact. The electrical heating performance section is critical, specifying requirements for actual power output, heating element resistance, and insulation resistance (minimum 50 MΩ). It also includes tests for resistance to electrical thermal shock, electrical heat endurance, and heating uniformity, ensuring the glass functions safely within an operating temperature range of -50°C to 70°C.
Testing methods
Testing procedures are designed to validate all technical requirements. Dimensional and visual inspections utilize calipers and steel rulers. Optical tests reference GB/T 5137.2 for transmittance and distortion. Environmental stability tests (heat, radiation, humidity) follow GB/T 5137.3. Mechanical tests include a steel ball drop test for penetration resistance and an air cannon ballistic test for high-speed impact resistance, referencing GJB 2464. Electrical and thermal performance tests, including insulation resistance and heating uniformity, are conducted according to GJB 961.
FAQs
What products are regulated under GB 14681.2-2006?
This standard regulates electrically heated glazing materials specifically designed for the front windows of locomotives and electric multiple units (EMUs). It covers both wire-heated (WL) and conductive film-heated (EL) glass types.
Are there any updates from the previous version of GB 14681.2-2006?
Yes, compared to the replaced GB 14681-1993, this version adds requirements for curved glass, raw materials, and corner size deviations. It also introduces optical distortion metrics based on automotive glass testing methods and adds ballistic impact performance requirements for high-speed trains.
What are the mandatory clauses in GB 14681.2-2006?
According to the foreword, clauses 7.5 (Optical Properties), 7.6 (Environmental Stability), and 7.7 (Mechanical Properties) are mandatory. Compliance with these specific clauses is legally required for market access.
The summary above provides a high-level overview of GB 14681.2-2006. To ensure complete compliance for your products entering the Chinese railway market, a precise and professional translation of the full technical specifications is essential. Purchase our high-quality English translation of GB 14681.2-2006 today to access all detailed parameters, tables, and testing procedures.
Applicability hints
- Type
- Product
- CCS
- Q34
- ICS
- 81.040
- Competent department
- Ministry of Industry and Information Technology
- Technical committee
- Ministry of Industry and Information Technology
Relationships
Partially replaces:GB 14681-1993