Non-welded piping solutions
Alternatives to welding tend to be more efficient and require less trained workers. Especially for pipe dimensions of single digit inches, several ways of connecting pipes without welding are possible. Let’s have a look at the most popular alternatives: cuttings rings, flaring, radial press fittings and fipeing.
Radial press fitting
To dive into the topic of welding alternatives one thing has to be made clear: For some applications, such as food processing lines, welding is still the first choice. However, for utility, control and energy lines that make up for a large part in piping, alternative pipe connections can add a good deal of process security and safe time and money. First of all, get your requirements straight. Does your connection need to be detachable? What is the pipe diameter and working pressure? What are the safety factors? As we compare the alternative connection technologies to welding, the crucial question may be: is the connection purely metallic? This is only the case when using cutting rings or fipeing a connection.
Working pressure (bar) versus dimensions (inches)
From narrow spaces to exposed conditions, the ease of installation weighs in the balance and is a direct benefit for the installer. Installation begins with: pipe preparation. Cutting rings need a pre-assembly of the ring to avoid unsuccessful connections. Flaring obviously requires a bulky flaring machine to prepare the pipes. Often, this cannot be done on-site, which reduces the flexibility of the installation team. Radial press fittings and fipeing neither require a pre-assembly nor preparation other a reasonably clean pipe surface.
Each alternative requires dedicated equipment to do the on-site installation. Flaring only needs little torque, thus smaller wrenches than cutting rings. This partly makes up for the high preparatory work. Radial press fittings and fipeing both require hydraulic driven press tools to do the task. At first glance, wrenches seem to be the most mobile equipment. If we have a look at what is needed to connect pipes with larger diameters however, the comparison of wrench to the press tool is impressive. The wrench exceeds the dimension of the press tools by far. Also, bigger pipe dimensions often need more than one installer to come up with enough force to turn the wrench. In this regard, alternatives with hydraulic driven tools come in handy.
Equipment to connect 1 1/4″ pipes. Wrench (cutting ring) versus press tool (fipeing).
From a commercial point of view, flaring comes last due to high initial costs as well as rather high material and maintenance costs. The economical benefits of cutting rings, radial press fittings and fipeing have approximately the same level. However, the pipe dimension range and the application requirements of the FIPE system are higher with equal equipment expenses.
|Cutting ring||Flaring||Radial press fittings||Fipeing||Welding|
|Hot work permits required||*****||*****||*****||*****||*|
|Pure metallic sealing||*****||*||*||*****||*****|
|Low fitting costs||****||**||*****||***||*****|
|Low equipment costs||***||**||****||****||**|
|Low maintenance costs||****||**||*****||*****||***|