To reduce the diameter of a PTFE (Teflon) thin wall pipe, a tool made of EN-2030 aluminium alloy has been used to date. We replaced this tool with one made of 1.4571 stainless steel. The task of the tool is to reduce the diameter of the pipe to the adequate final diameter.
When reducing the diameter of a PTFE thin wall pipe, the temperature of the tool is an extremely important factor, therefore it must be appropriate to ensure an adequate surface quality of the PTFE thin wall pipe.
In the graduate thesis we showed the influence of tool temperature on the surface of PTFE thin wall pipes. We were mainly interested in heating the tool and how the tool with inhomogeneous temperature affects the quality of the pipe surface.
We established that with old tools made of aluminium alloy EN-2030, uneven heating occurs, which in turn affects the quality of the pipe surface. Due to problems and shrinkage of the old tool, we decided to make a new tool made of 1.4571 stainless steel, which is inserted into the heating base made of aluminium alloy EN-2030. The new tool is heated evenly and therefore the pipe in the tool is also heated evenly, thus ensuring an adequate surface quality of the pipe. With the new tool, several pipes with a more adequate and higher surface quality are produced in the same time interval.
The tool heating process was controlled using a Fluke Ti400 thermal imaging camera. Thus, we further confirmed that the old tool heats up unevenly. We also established that the temperature of the new tool is homogeneous and appropriate across the entire surface of the tool. The surfaces of the pipes were also examined under an optical and scanning electron microscope.
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