Straight coupling with union SiGMA-Li PERTZPŚ2034 — 20 x 3/4 for PE-RT pipelines

Straight coupling with union SiGMA-Li PERTZPŚ2034 — 20 x 3/4 is a union-style transition fitting designed to connect 20 mm PE-RT tubing to a 3/4-inch threaded fixture. The coupling combines metal and engineering-grade plastic components to provide a mechanically secure connection between flexible PE-RT pipeline and threaded valves, manifolds or appliances. It is intended for plumbing and low-temperature heating systems where a robust, leak-resistant transition from polymer pipe to threaded hardware is required.

Advantages

The metal/plastic union design allows straightforward assembly and disassembly without damaging the pipe, while the union nut provides a tight seal under normal operating pressures. Compatibility with 20 mm PE-RT pipes makes the coupling suitable for common domestic and light commercial installations. Durable materials resist corrosion and mechanical wear, and the fitting is designed for reliable performance when joining polymer piping to standard 3/4-inch threaded connections.

Suitable for

• Connecting 20 mm PE-RT pipe to 3/4-inch threaded valves and fixtures
• Domestic plumbing systems including potable water lines
• Low-temperature underfloor heating and radiator circuits
• Serviceable connections where periodic disassembly may be needed

Key specifications

• Pipe compatibility: PE-RT, 20 mm outer diameter
• Threaded end: 3/4-inch male/female threaded fitting (union connection)
• Construction: combined metal and engineering plastic components
• Connection type: union-style mechanical coupling for push-on/insert pipe with compression/united sealing
• Intended use: plumbing and low-temperature heating systems

How to use

Prepare the PE-RT pipe by cutting it square and deburring the end. Slide the union nut and any internal sealing components onto the pipe according to the manufacturer's orientation. Insert the pipe fully into the coupling until it seats against the internal stop. Tighten the union nut by hand and then with a suitable wrench to the recommended torque; avoid over-tightening. Connect the 3/4-inch threaded end to the mating threaded fixture using appropriate sealing material on the thread if required by the installation practice. After assembly, pressurize the system and inspect for leaks at the union and threaded connection points.

Usage recommendations

Use with 20 mm PE-RT pipe only and follow pipe manufacturer guidelines for bending radius and support. Do not exceed the operating temperature and pressure limits applicable to PE-RT piping systems. If repeated disassembly is expected, inspect sealing surfaces and replace any elastomeric seals showing wear. When connecting to potable water systems, ensure components and any thread sealant comply with local regulations.