Visual Inspection
Coupling Housing: Visible cracks, deformation, or severe corrosion; extensive coating failure; inability to maintain structural integrity.
Sealing Gasket:Signs of aging (hardening), cracking, damage, or permanent deformation; loss of elasticity preventing an effective seal.
Bolts and Fittings: Stripped threads, severe corrosion, or breakage; inability to tighten properly, compromising connection reliability.
Performance and Operating Conditions
Pressure Failure: Persistent leakage at the joint during pressure testing that cannot be resolved by re-tightening; indicates the coupling fails to meet pressure-bearing requirements.
Service Life Exceeded: Usage duration far exceeds the design lifespan; prolonged exposure to harsh conditions (e.g., high temperatures, corrosive environments) leading to significant performance degradation.
Misalignment or Instability: Significant misalignment or wobbling at the pipe connection; the coupling's key (ridge) has completely disengaged from the groove and cannot be reseated or secured.
Compliance Assessment
Specification Mismatch: Coupling model does not match the pipe's nominal diameter or working pressure; fails to meet relevant standards and specifications.
Substandard Quality: Lack of product certification or inspection reports; material composition fails to meet national standards; presence of serious safety hazards.
