When selecting flanges, focus on verifiable parameters rather than relying on subjective judgment. Key steps include:
Material Verification: Check material certificates (such as quality assurance documents) to ensure compliance with application requirements. For instance, prioritize stainless steel or special alloys for corrosive environments, and alloy steel for high-pressure systems.
Compliance with Standards: Refer to industry standards such as HG/T20592 (a Chinese chemical industry standard), which governs dimensions, tolerances, and testing requirements to ensure compatibility and safety.
Specification Matching: Select based on pipe diameter (e.g., φ114) and nominal size (e.g., DN100); ensure the product's size range (e.g., DN10–DN2200) covers your requirements to avoid installation issues caused by mismatched dimensions.
Performance Parameters: Evaluate compressive strength (claims of "high-pressure resistance" should be backed by test reports), connection method (welding or bolting), and type (e.g., axial types are suitable for straight-line connections). Prioritize "Grade 1" products, which indicate superior quality control.
On-Site Testing: Before purchasing, request samples from the supplier to conduct pressure tests and verify sealing performance and durability.
