1. High-pressure/high-temperature applications (such as petroleum and chemical pipelines)
Welding is preferred:
Arc welding (such as SMAW and GTAW) or argon arc welding is used to ensure joint strength and sealing.
Bevels should be processed and heat input should be controlled to avoid deformation and residual stress.
2. Applications requiring frequent disassembly or maintenance
Flange connection:
Flanges are welded to the pipe ends and then secured with bolts. Suitable for valves, equipment connections, etc.
Pay attention to the compatibility of the flange gasket material (such as rubber or spiral wound gasket) with the media.
3. Low-pressure/small-diameter pipelines (such as water supply and drainage, mechanical transmission)
Threaded connection:
Tapered or straight threads are machined on the pipe ends and then screwed together with sealant or raw tape.
Pressure capacity is low (generally ≤1.6 MPa), and regular inspection of thread corrosion is required. 4. Special Needs
Compression/Clamp Type:
Uses specialized tools to compress the pipe fitting's sealing ring. Suitable for thin-walled stainless steel pipes.
Grooved/Grooved:
Requires additional groove processing for use with clamps. Suitable for fire protection pipes, etc.
Selection Considerations
Corrosive Media: For corrosive media (such as acids and alkalis), flanges with corrosion-resistant gaskets or fully welded connections are recommended.
Installation Space: For narrow spaces, welding or threaded connections are preferred to avoid excessive flange space occupation.
Cost and Efficiency: Welding is more expensive but more durable. Threaded/Compression/Clamp Types are faster to install but require more maintenance.
