Bolted coupling 3/4x20 with male thread

Product detailed description

Bolted couplings are commonly used in residential and commercial buildings for connecting plastic-metal composite pipes in heating and water supply systems. These fittings are particularly useful in underfloor heating installations, radiator circuits, and potable water distribution. Installers often prefer bolted couplings due to their ease of installation and compatibility with various pipe types. Unlike crimp fittings, bolted couplings do not require specialized tools, making them a practical choice for many applications.

When working with PEX-AL-PEX or PE-RT-AL-PE-RT pipes, it is essential to use fittings that ensure a secure and leak-free connection. Bolted couplings are especially suitable for systems where flexibility and long-term reliability are required. The use of tinned brass and EPDM sealing materials ensures compatibility with both hot and cold water systems. These fittings are often found in systems where frequent maintenance or adjustments are necessary, as they can be disassembled and reassembled without damaging the pipe or fitting.

Technical parameters

Installation and connection

Installation of the bolted coupling involves preparing the pipe end by ensuring it is clean and free of burrs. The coupling is then slid over the pipe, and the pipe is inserted into the fitting until it reaches the stop. A wrench is used to tighten the bolts, ensuring a secure and leak-free connection. It is important to avoid over-tightening, which can damage the sealing rings and compromise the integrity of the connection.

Common installation mistakes include using the wrong size coupling or failing to clean the pipe end properly. These errors can lead to leaks or reduced system efficiency. Installers should also verify that the pipe is compatible with the coupling and that the sealing rings are in good condition before installation. Regular inspection of the connection during maintenance can help identify and address potential issues early.

Compatibility and accessories

This bolted coupling is compatible with a range of PEX-AL-PEX and PE-RT-AL-PE-RT pipes, including those from manufacturers such as Giacomini, Barbi, and Viessmann. It is also suitable for use with stainless steel manifolds, which are commonly used in underfloor heating systems. When installing, it is important to ensure that all components are from the same system to maintain compatibility and system integrity.

Additional accessories that may be required include wrenches for tightening the bolts and pipe cutters for preparing the pipe ends. Installers should also have a supply of replacement sealing rings on hand in case of damage or wear. A related product, the bolted coupling 1/2x16 with external thread, can be used for smaller pipe sizes in similar applications.

Technical background for designers

The bolted coupling operates by securing the pipe within the fitting using a combination of mechanical force and sealing materials. The tinned brass body provides corrosion resistance, while the EPDM sealing rings ensure a watertight connection. The use of a brass tightening ring helps distribute the clamping force evenly, reducing the risk of leaks or damage to the pipe.

When integrating this coupling into a system, designers should consider the operating conditions, including temperature and pressure, to ensure long-term reliability. The choice of materials and design of the coupling also affects the system's efficiency and service life. Proper sizing and selection of the coupling are essential to avoid overloading the fitting and compromising system performance.

Service and operation

Regular inspection of the bolted coupling is recommended to ensure continued performance and to identify any signs of wear or damage. The sealing rings should be checked for cracks or deformation, and the bolts should be tightened if necessary. While the coupling does not require regular maintenance, any issues should be addressed promptly to prevent leaks or system failures.

During operation, the coupling should be monitored for any signs of leakage or pressure loss. If a leak is detected, the coupling should be disassembled, and the sealing rings replaced if necessary. The bolts should be retightened to the manufacturer's specifications to ensure a secure connection. Proper installation and regular inspection can help extend the service life of the coupling and maintain system efficiency.

Frequently asked questions

Can this coupling be used with PERT Frankische pipes?
Yes, the coupling is compatible with PERT Frankische pipes as well as other types of PEX-AL-PEX and PE-RT-AL-PE-RT pipes.

Is it suitable for use in potable water systems?
Yes, the coupling is suitable for potable water systems due to its use of EPDM sealing materials and tinned brass construction.

Can it be used in gas systems?
No, the coupling is not suitable for gas systems as it is not designed for that application.

What tools are required for installation?
A standard wrench is required to tighten the bolts during installation. No specialized tools are needed.

Documents for download

• Hygienically certified brass fittings for PEX-AL-PEX system (PDF)