Flanged ball valves with seals made entirely of PTFE are often no longer sufficient to meet the new, more stringent requirements regarding, for example, temperature/pressure, material properties and purity. Customised products are able to cover some of this demand. However, these are only available in limited quantities with long delivery times and at a high price. Very often now, it is the accident risks identified in safety discussions between operators, authorities and engineering partners that prohibit the use of standard ball valves – even though they could be used without problem in normal operations. The risks are taken very seriously in order to prevent accidents that could endanger both people and the environment; this now not only applies to the so-called developed world, but also to all projects in emerging and developing countries. There is a pronounced trend towards downstream customers demanding customised ball valves that meet their specific requirements, that can be produced in large quantities, and that are both affordable and available at short notice.
German manufacturer A+R has made it its mission to provide a versatile range of special sealing systems using an intelligent constructive modular system based on the advanced 2-piece, PTFE-sealed standard ball valve. These systems consist of, among other things, combinations of PTFE and graphite seals to both provide fire-safe properties and to avoid contaminating the product with carbon. This plays a decisive role in the production of, for example, HPPO hydrogen peroxides. To this end, several thousand ball valves have been supplied for projects in Southeast Asia and Saudi Arabia.
This same intelligent modular system is used for the metal ball-sealing systems. Wherever the temperature/pressure exceeds the level of PTFE-resistance or the input material for PTFE is incompatible, smart solutions are needed. This is also increasingly true for substances such as styrene, butadiene, phenol, polyol and the post-combustion of materials with toxic content to name just a few of the many fields of application. The demand for metal-seated seals for ball valves is thus growing exponentially.
