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Understanding terms related to Press Fittings and tools

The decision to move to a press system for heating, hot water or gas is becoming easier with the access to affordable quality M-Profile press tools like the battery operated Z-Press by Zupper. The range consists of two models, the PZ-1930 and PZ-1550 which are different machines and press different jaw sizes. The PZ-1550 presses M-Profile fittings up to 54 mm and is a larger machine for mechanical engineers and contractors installing larger pipe sizes. There are lots of hydraulic guns now on the market and they all seem to offer a similar operating press mechanism and warranty. Z-Press does stand out from the crowd though because it has a full service network within the UK. This means that if a Z-Press requires a service or maintenance there is an easy to access dedicated tool drop off. This can be organised once the Z-Press tool is registered on the Z-Press website and then a booking can be made with the details of where it is convenient to drop the press tool off. The M-Profile press tool drop off can happen in any leading independent plumbers merchants throughout the UK. This allows for a network of great stockists that are ready to support the M-Profile Z-Press tool.
As always in a professional industry there are some phrases and terms that are specific to the hydraulic battery operated Press world and these are explained below with the definition in the most simplest form.


The action of closing a fitting of various materials like stainless steel (inox) copper, or plastic. This is the fastening of two parts to create a connection using force, friction and cold welding. There is no brazing or hot welding (hot works) and it creates an extremely strong and efficient connection. Although the connection is permeant it does mean that there is less likelihood of leaks by movement as there would be in push-fit plastic or metal pipe fittings. Press can be used on plastic pipe that includes PEX, PB and with plastic fittings that are suitable for water, gas and central heating.


The action of deforming one part of a connecting joint to create a water, air or gas tight connection. There are two main types of crimping, hexagonal and indent (interference) the former is used for aluminium and copper and used within the electrical industry. The indent crimping method produces a lasting and reliable dent into the two materials and is common in the plumbing and heating industry. One drawback to crimping is that once performed it cannot be disconnected, which is not a disadvantage in a central heating system.

Press Cycle

The action of pressing a fitting to completion onto a pipe through a hydraulic action of compression, which is finishes with the crimping or deformation of the fitting and/or pipe. Most tools that perform a press cycle are hydraulic and use strong hard jaws to clamp the fitting and gradually press it into a new shape. The time it takes to perform this is the press cycle. It is also common for a tool to have a press cycle service requirement which is the number of press cycles it can perform until it needs an inspection or recalibration to be effective. The Z-Press from Zupper has 30,000 press cycles before it is required for servicing. The Z-Press also has a fast press cycle that speeds up installation time and gives a reliable crimp or indent connection every time.