JB/T 51109-1999

Manufacturers of internal combustion engines and bearing shell producers use this standard to grade and inspect main and connecting rod bearing shells. It helps them control product quality during production, ensuring that products meet either qualified or first-grade requirements. This standard is important for ensuring the reliability and consistency of critical engine components.

内燃机制造商和轴瓦生产厂使用本标准来对主轴瓦和连杆轴瓦进行质量分等和检验。它帮助企业在生产过程中控制产品质量，确保产品符合合格品或一等品的要求。本标准对于保证内燃机关键零部件的可靠性和一致性具有重要意义。

This standard specifies two quality grades (qualified and first-grade) for internal combustion engine main bearing shells and connecting rod bearing shells, covering quality indicators such as materials, dimensional tolerances, surface roughness, and bonding strength, along with corresponding inspection methods and rules. It applies to reciprocating internal combustion engines with cylinder diameters up to 200 mm. By providing clear technical requirements and sampling plans, the standard offers a unified basis for product quality grading, helping to improve the manufacturing quality and reliability of critical engine components.

本标准规定了内燃机主轴瓦和连杆轴瓦的合格品与一等品两个质量等级，涵盖材料、尺寸公差、表面粗糙度、粘合牢度等质量指标，以及相应的检验方法和检验规则。标准适用于气缸直径200mm以内的往复式内燃机。通过明确的技术要求和抽样方案，为轴瓦产品的质量分等提供了统一依据，有助于提升内燃机关键零部件的制造质量和可靠性。