As a longstanding specialist in the fabrication and welding of high-end pressure vessel structures, LTi Metaltech was tasked by their customer West Technology, with manufacturing a chamber pot pressure vessel with the capability to withstand both positive and negative pressures.
The vessel itself was designed to be used by West Technology’s end customer Megger, for the impregnation of electrical windings in one of their high-voltage testing machines.
In this project, LTi needed to identify new ways of improving the structure’s manufacturability, so they could meet their customer’s requirement for a reduced cost price point. LTi quickly recognised that they would need to make a series of radical changes to their customer’s original design specifications, if they were to resolve both of these challenges in alignment with the customer’s requirements.
There were many elements in the vessel’s original design specifications that presented LTi with challenges:
(This together with the extra complexity of some of West Technology’s original designs can be seen in the diagrams below Fig 1, Fig 2a & 2b and Fig 3).
Consequently, LTi would need to be extremely innovative to achieve the required Design for Manufacture changes necessary to improve the vessel’s manufacturability and reduce the total cost of producing it.
Following from detailed review of all aspects of both the original design stages and the related manufacturing processes, LTi’s expert team of innovative designers and manufacturers utilized techniques including 3D modelling to identify design and structural changes which would make the vessel more cost effective to produce.
Working to EN 13445 European Pressure Vessel Standards, which sets the minimum quality standards in the design, fabrication and inspection of vessels; LTi made a number of key changes:
These changes allowed LTi to reduce the total amount of assembly hardware required to fabricate the multiplicity of machined parts. Essentially this reduces the number of assembly steps involved, which further lowers the risk of any potential human errors and subsequent rework which can slow down the manufacture of a structure and push up costs.
(Photos below from LTi’s factory floor showing some stages during the chamber pot pressure vessel’s construction in Fig 11 and Fig 12)
LTi successfully met all the required design changes they set out to achieve, improving the manufacturability of the chamber pot and giving their customer a much more cost effective to produce structure that was still fit for purpose.