Focus on Pumps: Shifting fluids reliably, safely and economically

Author / Editor: Charles Butcher* / Charles Butcher

Pumps are the workhorses of every process plant, not to mention plenty of auxiliary equipment and even portable test gear too. This run-round of recent developments takes in centrifugals, vacuum pumps, positive-displacement pumps and gas sampling units.

Related Vendors

The design of the Clawvac vacuum pump allows the user to disassemble and clean the working parts quickly and easily, since the rotors can be removed without having to readjust the synchronization.
The design of the Clawvac vacuum pump allows the user to disassemble and clean the working parts quickly and easily, since the rotors can be removed without having to readjust the synchronization.
(Source: Leybold)

Known for their flexibility and portability, air-operated double-diaphragm (AODD) pumps are a good choice when all leakage must be prevented. The new ADX series from Almatec (photo, below left) has been developed to replace the company’s legacy Chemicor AD Series pumps, incorporating an array of design enhancements that provide simplified maintenance, improved cleaning and increased safety. Wetted housing parts are constructed from precision-cast stainless steel, while the non-wetted parts are available in three different plastic materials to accommodate a variety of applications and temperatures.

When combined with the new series’ standard features — including easy start-up, rotating suction and discharge ports, gentle displacement, dry-running and self-priming operation, no diaphragm discs, and Almatec’s patented maintenance-free Perswing P air control system — these pumps set an industry-leading standard in industrial applications, the company claims, enhanced by the availability of flange options (DIN and Ansi) as well as additional connection options (sanitary threads, open butt welding).

The series is currently available in ADX20 (3/4") and ADX25 (1") sizes and in two variations that meet Atex requirements. Additional sizes are under development. The new series pumps are also offered with Almatec monitoring systems such as stroke counting, diaphragm sensor and barrier chamber system.

Centrifugals Take the Heat

Turning our attention to centrifugal pumps, Blackmer has recently announced the launch of its new System One High Temperature series (photo, p.45, bottom left). Utilizing high-temperature flanges, elastomers, and a unique centerline mount that supports high temperatures, the new series pumps are able to exceed the 400°F (200°C) standard temperature limit of conventional centrifugal pumps. This unique design feature allows the series to safely and reliably transfer critical and valuable fluids in a wide variety of high-temperature applications, including thermal oils, petrochemical products, plastics, paper, and more, states the company. The new series is pre-configured to meet temperature requirements of up to 450°F (232°C) with the 450°F Line, 650°F (343°C) with the 650°F Line, and even 750°F (398°C) with additional configurations and factory consultation. These pumps have been specifically designed to increase the temperature limits for Blackmer Frame A and Frame M centrifugal pumps while offering the same mechanical advantages and proven design features that provide maximum reliability and long life, adds the firm. The new pumps offer capacities up to 1,400 gpm (5,299 L/min), and incorporate high-temperature bushings, fasteners and paint. They are backed by an industry-leading five-year performance assurance for the power end, plus a one-year performance assurance for the mechanical seal.

Flexible Gas Sampling

At the opposite end of the duty spectrum, Bühler Technologies has introduced its latest P1 series of sample gas pumps to the market (photo, p.45, bottom right). The DC-drive versions of the P1.xx are now available with IP 20 protection. Both OEMs and end users will appreciate the rugged design and corrosion-resistant materials, resulting in long service life paired with low operating costs, the company claims. The P1.1 and P1.1E models are designed for direct installation in stationary or mobile analysis systems, in safe areas. While the P1.1 has an open electric drive (equivalent to class IP 00 protection), the P1.1E comes with a vented cover that provides IP 20 protection class and so can be employed as a stand-alone unit.

The P1.2 and 1.2E Series are suitable for flammable gases in equipment group II, equipment category 3G, gas group IIB and temperature class T4, and are immediately available for delivery. This expansion of the range enables sampling a large group of gases with flammable components and solvents, for example methane in biogas or processes containing ethanol. The Atex code is II 3G/- c IIB T4.

All versions of the P1 series pumps are available with an integrated adjustable bypass valve. This allows operators to pre-set flow rates below the maximum flow of 280 NL/h and eliminates the need for separate regulators.

Pumps of the P1.xx series feature the same one-piece PTFE bellows design as all Bühler sample gas pumps. All other wetted parts are made from PTFE or equally resistant materials. The power supply can be either 115V/60 Hz, 230V/50 Hz AC or 12/24 V DC. The IP 20 cover also provides a 3 m flying lead for power connection. All the pumps have a compact design and are easy to install.

Positive Displacement Pumps

Apart from the AODD pumps mentioned above, the vast range of positive displacement pumps also includes gear pumps and progressing cavity designs. As an example of the former, Maag Group has recently added the FQ “quick cleaning” option to its portfolio of gear pumps (photo, p.46, bottom).

Available both as a stand-alone range of pumps and as an upgrade kit for existing CX, TX, FX and DX models, the FQ design allows the pump to be disassembled quickly without needing to dismantle the drive shaft from the drive motor and the seal.

The upgrade is aimed at production facilities handling multiple colors or additives, where there may be a constant need to clean and wash the transfer line at the end of each production batch. The new models allow customers to improve their production and maintenance routines without compromising on the operating characteristics they have come to expect from their Maag pumps. The kit combines a high degree of flexibility and functionality with easy maintenance and parts replacement, adds the firm.

In progressing cavity pumps, the Nemo FSIP design from Netzsch can be used in nearly any area of industry, the company claims, since it is capable of pumping and precisely dosing a great variety of different substances. To further expand the capacity range, these models are now available in stainless steel in sizes NM053, NM090 and NM105; previously only cast iron pumps were available in these sizes, Netzsch notes. The FSIP design is especially suitable for wear-intensive applications that requiring frequent servicing, since the design makes maintenance easy. The pump is designed in such a way that the housing itself functions as a support and orientation guide during maintenance, making sure that each part fits “automatically” into its appropriate place. Changing all the wear parts takes less than half the time required for traditional designs, the firm claims. In stainless steel, the pump is ideal for temperatures up to 80°C and pressures up to 9 bar. The suction flange can be supplied left- or right-handed, or vertical.

From Industrial Vacuum …

With the new oil-free DSS scroll vacuum pump, Atlas Copco is expanding its range of dry industrial pumps. The robust, low-wear pump is designed to operate in the rough vacuum range, providing stable vacuum down to 1 mbar and maximum productivity at low to medium flowrates, the firm says. The new DSS vacuum pump is particularly suitable for applications in pharmaceuticals, food packaging and processing.

A key feature of the innovation is its simple and effective operating principle for gas handling, says the firm. Inside the pump are two intermeshing, spiral-shaped screws made of aluminum. One of these is fixed, while the other rotates to enclose pockets of gas. The design is characterized by low energy consumption, low life cycle costs and user-friendly operation, the company says. Dry running means no oil changes, and also no need to replace the exhaust filters, leading to relatively low maintenance requirements. Also contributing to reduced service costs is the removable front cover, which simplifies access to the interior of the pump.

Extensive testing by TÜV Rheinland in 2019 showed no traces of oil whatsoever in the exhaust air stream, ensuring a maximum of cleanliness and safety for both the production environment and personnel. Based on the TÜV results, the DSS vacuum pump has been certified in the top Class 0 for oil-free performance.

Another dry pump targeting rough vacuum in industrial processes is the Clawvac from Leybold (photo, below). Besides food processing, packaging and environmental technology, this uncomplicated model is also suitable for drying and sterilization processes.

Vacuum is created by a pair of claw rotors rotating within the pump stator completely without contact, and hence with zero wear. Stainless steel rotors and a corrosion-resistant coating inside the vacuum chamber ensure reliability even under harsh process conditions, the company says.

When maintenance is required, the vacuum generator is easily accessible thanks to the pump’s self-supporting construction. Opening the case and cleaning the working parts takes just a few minutes, Leybold claims, and the rotors can be removed without having to readjust the synchronization. No maintenance should be required apart from replacement of the drivetrain oil and lip seals every 20,000 h.

The company is also offering new multiple-pump systems based on Clawvac pumps to provide a redundant plug-and-play solution. Two, three or four pumps within a single housing use intelligent control to provide flexible and energy-efficient vacuum in pneumatic conveying, CNC machining, plastics processing, drying, and centralized vacuum installations.

… to Plasma Physics

For a very different class of vacuum application, the Hi Pace 350 and 450 turbopumps from Pfeiffer Vacuum (photo, left) target high-tech coating processes, semiconductor manufacture, and analytical techniques such as mass spectrometry and electron microscopy, plus metrology, particle accelerators and plasma physics research.

The new turbopumps combine high performance with low weight and a small footprint. A hybrid bearing design — with ceramic ball bearings on the backing-pump side and permanent-magnet radial bearings on the high-vacuum side — helps to ensure robustness and reliability, says the firm.

The sophisticated rotor design of these turbopumps provides an ideal combination of compactness and high performance in the range 300–700 l/s. Pumping speed is especially impressive for light gases, Pfeiffer Vacuum says.

The pumps can be installed in any orientation and are claimed to run for up to five years between services. The integrated drive electronics offers various communication interfaces including Profinet and EtherCAT.

* Almatec: +49 2065 89205-0 Atlas Copco: +49 201 2177-0 Blackmer: +1 616 241-1611 Bühler: +49 2102 4989 Leybold: +49 221 347-0 Maag: +41 44 27882-00 Netzsch: +49 8638 63-0 Pfeiffer Vacuum: +49 6441 8020