PECM Issue 14 2015 | Page 5

Colin Hartop ESTS points out Bürkert Type 2000 steam valve The valve body selection was also important to provide a compact solution; the bodies of Bürkert’s latest generation of angle seat valves are considerably smaller than other older designs and helped to ensure a compact, but reliable final product. A number of the angle seat valves were also supplied with a male thread which is a specification developed for Control Steam as a first for this application. This reduced inventory purchase costs for the machine builder by reducing the number of joints and connectors required to construct the piping circuit. Essentially a benefit just to the OEM, it does however add to the overall cost competitiveness of the machine. In order to guarantee savings in the total cost of ownership, the valves that control the fluid and steam in and out of the heater have been adapted to cope with the high temperatures. There are two actuated ball valves being used – one to control water flow into the header tank and another to drain the flash steam generator of any residual fluid; this has an extension piece to keep the heat transfer to a minimum to protect the actuator which inherently has a lower temperature protection rating than an angle seat valve. The lack of a conventionally heated pressure vessel boiler in the machine is a crucial aspect in the reduced maintenance cost calculations, as they are subject to comprehensive legal service and inspection procedures. The physical cost of these checks amounts to over £1,000 on a bi-annual basis, plus the cost of two days of operational downtime. Experience also shows that immersed elements either in chamber or when fitted to conventional electrically heated steam boilers are prone to failure with typical costs associated with replacement at well over £1,000. Bürkert Type 2000 angle seat steam exhaust valve The flash steam generator in the LAB300 is used to create steam ondemand. This is far more efficient than a more conventional pressure vessel boiler arrangement that heats a volume of water to produce steam and then maintains it throughout the day, constantly using energy to battle insulation losses. The ESTS exclusive design employs ceramic heating elements cast into a solid aluminium heater matrix. The unit attains operational temperature in a matter of seconds and converts water into steam on an on-demand basis, rather than maintaining a pressure vessel reservoir. An average usage cycle consumes just 10kWh which ESTS estimates will provide a 50% reduction in energy costs. Issue 14 PECM 5