A new process, InnerArmor, from a Wallwork Group company, Tecvac, is able to extend the service life and effectiveness of pipework, pumps, valves and other hollow process vessels.

These can be can be severely affected by corrosion, erosion, fouling and wear, particularly in oil and gas exploration and production, downstream petrochemical processing, chemical plants and water industries where downtime can be very disruptive and expensive. Using the technique of plasma-enhanced chemical vapour deposition (PECVD), Tecvac applies even, pin-hole-free, thin films of highly resistive materials such as diamond-like carbon (DLC), titanium carbide and other resilient materials.

Alternative approaches, such as the application of conventional metal coatings to internal surfaces can be difficult, especially in long lengths of pipe or plant with complex geometry. Similarly, fabricating pipes and plant from exotic metals and alloys that have strong resistance is expensive and operationally disruptive when these metals are not
readily available.

The company is able to fine tune the coating to optimise characteristics such as hardness, wear and erosion resistance to abrasive solids such as sand and grit, or chemical resistance to acids, salts and hydrogen sulphide. Applicable to mild steel and other common metals, coatings typically vary from 30 to 80 microns.

Tecvac is well known for its technical standards

InnerArmor coatings may be applied as single layer, but commonly a multi-layer, multi-material film will be applied to optimise performance. Stronger and subject to less stress than single layer coatings of the same thickness, multi-layer coatings have longer service life to maximise plant uptime.    

The InnerArmor PECVD method uses the pipe or process vessel as the reaction cell. Insulated collars link the vessel to positively charged anodes via which the source gas is pumped at a prescribed pressure and temperature. Ionisation of the gas results in even deposition of the coating on the inner surface. Process cycles determine the overall depth of the finished film. In addition to protecting the pipe from attrition by the contents, the technique also protects pipe contents from contamination by failing pipe material so preserving product quality and value.

Operating under licence from InnerArmor developers Sub-One Technology of California, Tecvac shares world-wide technical applications experience. Pump and piston chambers and other complex shapes can be coated effectively as well as pipe lengths of up to three metres. Environmentally benign, the PECVD process produces no harmful waste streams or volatile solvents and has a low carbon footprint due to a relatively low energy input.

EXPERTISE
InnerArmor is just one of a range of processes available from Tecvac and the Wallwork Group. As surface treatment specialists, the company can apply processes that improve hardness and resistance and which improve natural surface lubrication. These extend the working life of components in harsh environments and improve plant efficiency while lowering overall life-time costs. The company provides service to clients in demanding fields such as aerospace, energy, nuclear, motorsport and medical devices. Service is backed by extensive research and development capability to optimise processes before scaling up for full production.

Tecvac operates to ISO 9000 and BS EN 9100 aerospace quality standards and currently holds Nadcap approval for coatings. It can also design, build and service a range of specialist vacuum equipment for customers world-wide with high tech plants installed and working in more than 20 countries.

The company has a large and well equipped R&D department and laboratory dedicated to the development of advanced surface engineering processes, novel applications and new process equipment. This helps customers with specific issues they need solving. It also has strong links to a number of research and teaching organisations.

Tecvac operates a reliable collection and delivery service which, together with other group sites in Manchester and Birmingham, covers most areas of the UK. It ensures the logistic elements of the service are catered for whatever the
customer needs.