APV Launches High Efficiency Self-Priming Pump

The Ws+ incorporates many technical features that contribute to an outstanding combination of efficiency, cleanability and flexibility. This latest generation of self-priming pumps is designed to deliver technical and commercial benefits in response to market requirements.

As usual, improvement in energy consumption is a priority. The rising power characteristics of the Ws+ series result in a reduction of up to 49% in energy consumption by comparison with the APV ZMS self-priming pump. This means that an investment in the new pumps can be justified by a surprisingly short pay-back.

Although the Ws+ pump has a smaller motor than a traditional self-priming pump, it is capable of carrying out the same duty, but at greatly reduced noise levels. As a result of the new hydraulic design, the pump records lower noise levels than any of its competitive equivalents based on the liquid ring design.

The Ws+ pump is designed for hygienic applications and easy cleanability. APV’s W+ range was approved to EHEDG and American 3A sanitary standards, and the new Ws+ is designed to comply to the same high standards. Within the EHEDG certification, the Ws+ can be used for several applications where two pumps are normally required, such as pumping media and CIP cleaning.

Flexibility is also greatly improved versus traditional products. All self-priming pumps are equipped with a fixed diameter impeller, which cannot be changed, such that each pump only has a single performance curve. This prevents performance being optimised to match specific applications. Now, with the introduction of the new Ws+ impeller technology, the diameter can be customised in the same way as for a centrifugal pump. The flexibility is outstanding, with a flow range up to 90 m3/h and pressure up to 6 bar.

The design of the impeller also decreases the likelihood of damage by small particles in the liquid. On traditional self-priming pumps, the inclusion of several vanes within the impeller ring reduced the clearance past the inlet to as little as 0.2mm. This has been greatly improved by the use of the conventional open type impeller.

The Ws+ pump has a single mechanical seal (Silicon Carbide/Carbon) suitable for a wide range of products fitted as standard. A flushed version with Silicon Carbide/Silicon Carbide seal faces is available as an option for more arduous duties. Seals can easily be changed and all variations can be fitted to the same pump.

Finally, as the Ws+ is based on the W+ series, many of the spares parts, including the back plate, gaskets and seals are identical, resulting in reduced inventory requirements.

APV upgrades and extends the DW range of rotary lobe pump

Since its launch three years ago, the DW rotary lobe pump has proved highly successful for the careful handling of high-viscosity or delicate products. Renowned for its uncompromising quality, the range will be extended in Spring 2002 to include 24 models with flow rates up to 600 m3/hr.

As with all APV’s high quality product range, the DW pump is designed for economical operation. Due to an improvement in hydraulic performance, it is possible to select a smaller pump than before, resulting in lower running costs.

Technically, the DW pump includes a number of unique features, including an increased inlet behind the rotors, resulting in a low NPSH requirement, decreased noise at high speed, and minimum local cavitation. In addition, due to its specially patented rotor tips and grooves, the pump runs without pulsations when handling highly viscous products. This ensures the steady filling and discharge of the product, and extends the lifetime of valves and instrumentation.

The pump is frequently selected for its ability to successfully handle delicate products. Its gentle pumping action ensures minimum damage to particles. Equally important is its flexibility – thermal jackets can be fitted as an option to facilitate the heating or cooling of the pump chamber prior to product entry. This prevents even minor temperature changes, which can cause severe damage to sensitive products.

Certified to meet EHEDG and 3A sanitary standards and with all seal materials in accordance with FDA approval, the DW pump is designed for easy maintenance and features a front loaded shaft seal. Irrespective of whether the pump is fitted with the standard single mechanical seal (Silicon Carbide/Carbon) or the optional flush version (Silicon Carbide/Silicone Carbide), all seals can easily be changed without having to disconnect the pump housing or pipework. There is also easy access to other key components, such as the gearbox.

Easy cleanability is built into the design - the pump, including the pressure relief valve, is totally CIP cleanable without special procedures.

The DW pump is also extremely versatile. If desired, it can be used as a CIP feed pump, eliminating the need for an additional pump and the associated plant routing. Furthermore, it is possible to change the inlet / outlet orientation from vertical to horizontal within minutes, simply by disconnecting the feet. This also means that a single pump head is suitable for a pump in either configuration, thereby reducing spares requirements.

All APV pumps reflect the excellent quality for which APV products are renowned, and these new additions to the range are no exception. For further details or information about these or any of APV’s other products, please circle the enquiry number on the form at the back of this publication.

About APV

APV is a world-class supplier of process engineering and automation solutions to the food, beverage, pharmaceutical and healthcare industries. From the supply of engineered components through to a complete process plant equipped with latest automation technology, we specialise in helping our customers to improve their plants' performance and profitability. Excellent design principles are used to ensure maximum operational efficiency ... And this is maintained throughout the life time of the plant by a range of support services, carefully tailored to our customers' needs.

APV became part of the Siebe Group of companies in June 1997. With the acquisition, Siebe plc, already a major player in the Chemical, Oil and Gas, Utility and Pulp, Paper and Metals sectors added Food, Dairy and Beverage to its field of expertise, at the same time strengthening APV's position in these markets.

In February 1999, Siebe merged with BTR, a giant in industrial manufacturing and engineering, to form Invensys, a global engineering and electronics company with over 80,000 employees.