ARI-Armaturen Announces Automatic Bottom Blowdown Valve for Steam Quality

- Automatic operation helps increase boiler house efficiency and reduce resource costs

21st March 2007, Tewkesbury - ARI-Armaturen, worldwide leaders in the manufacture and supply of process valves, has announced the availability of the new ARI-STEVI BBD - a bottom blowdown valve with pneumatic actuator that effectively removes impurities to maintain optimum steam quality and boiler operation.

Boiler water contains dissolved and suspended solids and spent chemicals which, unless removed, will form a sludge in the bottom of a steam boiler. Eventually this will lead to blocked blowdown connections, boiler damage and impaired heat transfer, that affects boiler efficiency and potential catastrophic tube failure.

Many processing operations also aim to reduce staffing levels in their boiler houses, resulting in an increased demand for automatic operation of the bottom blowdown valve. Electrically operated valves are not generally suitable for this application as they cannot operate quickly enough, and compressed air is not always available as a motive power. To meet the requirement for a valve that satisfies this specific application, complies with stringent boiler house regulations and automates a manual process, ARI-Armaturen has developed the ARI-STEVI BBD bottom blowdown valve.

ARI-Armaturen’s automated solution is a large bore valve located at the bottom of the boiler which can be opened and closed very quickly. The valve is operated to give a 3 second blast which removes sludge in the immediate vicinity of the valve. The boiler is then left until the next shift, allowing time for the sludge to re-settle until the valve is operated again. It is proven that more regular 3 x 3-second blasts per day is a much more effective process than a 9-second blast once per day, for example.

Optimising Steam Quality
This application is very arduous as water at saturation temperature from inside the boiler is vented down to atmospheric pressure. This results in a substantial proportion of the water ‘flashing’ aggressively to steam over the valve seat, with the attendant risk of erosion and damage unless a purpose designed valve is used.

There are also industry regulations and best-practice engineering factors to consider- the valve should close automatically; flow through the valve should close the valve; and in multiple-boiler houses there must be a means to prevent more than one boiler being blown down at once. In manual operations a removable operating lever is required but if automatic control is to be used, the control system must include interlocks.

The basis of the ARI-Armaturen bottom blowdown valve is the well-proven carbon steel (PN40) 440 control valve body, operated by a unique removable lever to comply with boiler house regulations. Extra options can also be supplied to simplify installation including a three-port solenoid to control the actuator or motive fluid in and out, an end of travel switch to give remote indication of valve position and alternative gland packing to allow operation at temperatures of up to 450 oC

The ARI-Armaturen bottom blowdown valve is available in sizes DN25, DN32, DN40 and DN50 to cover most boiler house applications. The new ARI-STEVI BBD further extends the company’s range of specialist valves, and underpins the company’s philosophy of being a one-stop-shop for controls and pipeline equipment in the industrial, processing technology and plant manufacturing industry.

About ARI-Armaturen
For more that 50 years ARI-Armaturen has been designing and manufacturing specialist valves used for isolating, securing, controlling and steam trapping across a wide range of industrial processes, from process engineering, chemicals, shipbuilding to building automation. Offering a one-stop solution for all valve requirements, customers can profit from the complete ARI range of butterfly valves, globe valves, control valves, safety valves, strainers/check valves, or steam traps. All designs undergo stringent in-house testing and the valves are renowned for their high operational safety and reliability based on leading-edge manufacturing technology. ARI-Armaturen offers speed, expertise and superior performance, based on the highest quality standards. The company boasts 10,000 products with more than 100,000 variants. For more information visit www.ari-armaturen.com or call 01684 275572.