Welded vs Threaded Steel Pipe Joints: Which Meets Fire-Protection Codes and Performs Better On-Site?

For fire protection systems requiring Class 150 pressure rating, threaded joints using certified malleable iron fittings generally offer superior code compliance and installation efficiency compared to welded connections.

Code Compliance and Certification

Threaded joints utilizing galvanized malleable iron pipe fittings with FM/UL certification directly meet international fire protection standards. These pre-certified solutions eliminate the need for additional testing that welded systems often require. JIANZHI's 43 years of manufacturing experience ensure that every threaded fitting maintains consistent quality and compliance with global standards, including TSE, ABNT, and CE.

Installation Efficiency and Quality Control

Threaded connections demonstrate clear advantages in project execution:

☑ Rapid assembly without specialized welding equipment or certified welders

☑ Consistent quality without relying on individual welder skill

☑ Immediate pressure testing capability after installation

☑ Significantly reduced installation time and labor costs

Maintenance and System Modifications

The modular nature of threaded systems provides long-term benefits:

→ Simple disassembly for inspections and maintenance

→ Easy system modifications or expansions

→ No hot work permits required for future changes

→ Minimal downtime during repairs or upgrades

Performance in Class 150 Applications

For fire protection systems operating within Class 150 parameters, our black malleable iron pipe fittings and galvanized malleable iron pipe fittings deliver:

• Reliable pressure containment

• Superior corrosion resistance (galvanized version)

• Leak-free performance with proper installation

• Long-term system integrity

Conclusion

While welded joints have their place in specific applications, threaded joints with certified malleable iron fittings provide the optimal balance of code compliance, installation efficiency, and long-term maintainability for fire protection systems.

→ Choose Certified Threaded Solutions for Your Fire Protection Projects

Our FM/UL certified malleable iron pipe fittings ensure code compliance and installation efficiency for your Class 150 fire protection systems.

Contact us for certification documents and technical support on your next project.