Ian Crickmore, piping systems product manager for Geberit UK, manufacturer of sanitary, supply and HDPE drainage systems, considers the advantages of the modern plumbing methods over traditional jointing of pipework
Press fitting is still considered a relatively new development in plumbing, despite it having been around for more than 40 years.
Perhaps this is because it is perceived as innovative because, unlike its rivals, it involves no hot works or hazardous substances.
The technique involves making joints by inserting the pipe and fitting together and pressing the fitting socket and the pipe using either a hand-operated or an electrical press-fitting tool.
It was originally developed for commercial use but is increasingly being used domestically. And it is becoming a popular jointing method for plumbers.
The key advantage of press fitting is the reduction of installation time which, in turn, leads to other benefits. Mapress, Geberit’s metallic pipework press-fitting system, typically takes less than half the time of traditional threaded steel jointing systems.
Installation times are reduced in several areas. Jointing is a simple process – cut the pipe to size, debur the inside and outside, mark the socket insertion depth on the pipe, push the pipe into the socket of the fitting, then press the joint and connecting pipe using the pressing tool. Immediately, the most time-consuming process of traditional methods is removed, whether it be threading, soldering or welding.
Furthermore, installation uses components assembled with dry joints, with pressing following later. This is useful for working at height or for tricky positioning; traditional jointing in such circumstances can add time and components to a job. Also, the components can be pre-fabricated on or off-site before installation, which saves more time.
Press fitting does not require the use of sealants, tapes, fluxes or solder and is therefore cleaner and safer. And a hot works permit is not required.
One possible disadvantage with the technique is overlooking a press connection. Using the Geberit system, however, this issue is addressed. Geberit has developed leak-when-not-pressed technology, with a patented ‘O’ designed to let water past on test when not pressed. Simply isolate the water supply, press the connection and the joint is made; no need to drain down.
To ensure that the controlled deformation of the seal actually occurs, all pipes and fittings can be connected using the range of pressing tools offered. Geberit is the only manufacturer that guarantees the correct deformation of the seal ring repeatedly.
Geberit offers two press-fitting systems, Mapress and Mepla. Mapress is available in four materials: stainless steel, carbon steel, copper and CuNiFe. The extensive range of pipes and fittings make it ideal for a range of applications including hot and cold water, heating, chilled water, solar systems, compressed air and gases, as well as many industrial applications. Sizes range from 12mm to 108mm offering a 16 bar working pressure. The standard seal ring working temperatures are -20?C to 120°C. Alternative seal rings are available for a range of applications and higher temperatures.
Geberit Mepla is a multi-layer pipe composed of three layers. The outer layer is hard-wearing HDPE. The inner layer is Pex. And both are bonded to an aluminium middle layer. This provides stability and a barrier to oxygen diffusion. Mepla is designed for hot and cold water, heating and chilled water distribution.
The pipe’s inherent flexibility means it can be bent either by hand or using a bending tool. This gives the installer the opportunity to reduce the number of fittings used. And it makes it ideal for a range of installations including where access is restricted, for example, across congested ceiling voids.
Mepla is available in external diameters ranging from 16mm to 75mm. Diameters up to and including 26mm are available in 5m lengths or 50m rolls. Larger diameters are available in 5m lengths. Mepla offers a minimum service life of 50 years at 00C to 70°C, and pressures of up to 10 bar.
Geberit’s Mapress press-fitting system have total installed costs of 27% less than traditional screwed steel pipework. Mepla has reduced total installed costs of 12% compared with conventional copper-based systems incorporating pre-soldered joints.
Press fitting is a simple cold process, requiring minimal training. But Geberit offers free training, either on site at installer premises or at the Geberit Training Centre in Aylesford Kent.