Stainless Steel Pipe System Specifications from ACO Polycrete

ACO Pipe stainless steel pipe systems: The right specification.

The resilience of stainless steel offers a major advantage over cast iron and PVC above ground, as well as below. If a truck reverses into a cast iron or PVC downpipe, the impact may well fracture the pipe, while stainless steel is more likely to suffer an indentation without fracture, that can be more economically and conveniently fixed.

All of these points underline the fact that stainless steel drainage products reduce risk for all parties, from the manufacturer to the supplier, the specifier, the installer, and, finally, the end-user. However, improving the specification of pipework and drainage systems for healthcare environments is not simply a matter of adding some stainless steel components to your system and giving the matter no further thought.

For example, mixing materials can pose significant problems, even when one of those materials is stainless steel, and good engineering practice dictates that different metallic materials should not be used in direct contact.

A poorly specified system that, for example, uses cast iron or galvanised steel as a hidden component connected to a visible stainless steel drainage grating, chosen for cosmetic effect, can be a false economy as the contact between those two different metals will result in galvanic corrosion.

Similarly, if you are designing a system in which acids are present, you need the help and advice of an experienced manufacturer that understands the corrosive effect of those acids on metals; there are over 150 grades of stainless steel, and an expert supplier can tailor the materials used to best resist the corrosive effect of each given acid. Even 316 stainless steel, which contains molybdenum, and offers an even more resilient option than the more commonly used grade 304, can be vulnerable to certain chemicals, such as hydrochloric acid (HCI) and sulphuric acid (H2SO4).

The right specification can, in fact, only be made by first carefully considering the drainage performance requirements of a hygiene-critical environment and understanding the corrosive nature of the liquids that the system will be handling. Informed material selection can only be made using the right criteria and an awareness of the limitations, and this is best achieved by working with a supplier that understands the issues and can offer expert advice.

Making a checklist

In all applications, but particularly within the healthcare sector, a corrosion resistance checklist will help ensure that no crucial issue is overlooked during the specification process. A checklist needs to include questions such as:

'Are there chemicals contained in the fluid that is being handled?'
'If so, what is the concentration?'
'What is the temperature of the solutions?'
'How long will materials be exposed to the solution - continually, or once per day during a wash-down routine?'

Some of these questions may sound obvious, but are not always asked, and particularly those regarding temperature. However, they are all key questions that must be addressed in order to move towards the selection of the most appropriate stainless steel grade and the right seal materials to match.

Fabrication needs careful consideration too. Fabrication methods can introduce surface defects and imperfections, such as the chromium depletion that follows the welding process. To restore full corrosion resistance properties to stainless steels, fabrication finishing processes are necessary, and engineers, contractors, and architects that are technically informed on points such as this will produce the best designs.

Considering the resilience of these microorganisms only serves to underline the need for specifiers and installers to minimise and control the risk of contamination by making informed decisions from the outset. Careful planning of the drainage system, correct choice of materials and installation techniques, and a design that allows efficient maintenance are key to controlling these microorganisms.

Stainless steel pipework and drainage channels clearly offer the potential to provide healthcare institutions with long, reliable service, as well as to get the best value from available budgets, and to safeguard patients. If specified correctly by technically informed designers and installers, all parties will be risk protected, and will reap the benefits of the many innovations and enhancements that have made stainless steel components so effective in hygiene-critical environments.

Features of ACO Pipe include:

Range of pipe diameters available: 50mm, 75mm, 110mm, 125mm, 160mm and 200mm available
Socketed end profiles provide a modular push-fit system, that offers all the time saving benefits of traditional PVC pipe systems
Double lip seal on all joists ensures a trouble-free, reliable system
Full range of angles, branches, accessories and installation devices reduce the amount of on-site cutting and installation time