Vacuum Pump Evolution
Despite the maturity of vacuum pump designs, manufacturers show even in well-established
technologies key innovations are there for the taking.
Vacuum pumps are the veteran workhorses of the laboratory, providing the mechanical force for a host of research-related tasks that require precise atmospheric control. Over the last 100 years, a number of well-established pump designs have come to
dominate the market. And for decades, many varieties of pumps have
seen just incremental changes.
This is not for lack of competition. More than 450 vacuum pump
companies now operate globally. Because of this competition, vacuum
pump vendors must invest in new technology when it becomes practical, or when development dollars are available.
At KNF Neuberger, Trenton, N.J., the diaphragm pump is one of
their key products. A couple of years ago, the company launched a
new type of diaphragm that features a level of control not typically
seen in a standalone vacuum pump. Earlier this year, prompted by the
success of their prior launch, the company released a new pump that
elevated power, reduced footprint size, and improved the desirable
For Pfeiffer Vacuum, Nashua, N.H., rotary vane pumps are a big
component of their business, and the company markets several lines
to suit different needs for pumping speed, power, and relative cost.
One of these pump lines has recently adopted a revised type of drive
coupling that preserves performance while lowering operating costs.
Remote control for vacuum pumps
Controller-managed vacuum pump systems have become an increasingly regular sight in the laboratory. Enabled by rugged electronics and
touch-activated interfaces, wireless control systems offer the ability to
manage vacuum equipment efficiently and quickly. Less fiddling with
analog controls saves the researcher time and often improves results.
“Originally, laboratory pumps were standalone units,” says Dan
A new line of rotary vane pumps launched this year by Pfeiffer Vacuum
take advantage of the energy- and operating oil-saving properties of magnetic couplings. Image: Pfeiffer Vacuum
McDougall, senior manager of Laboratory Products at KNF Neuberg-
er. “Over time, there became a market need for controlling the vacuum
process. This was accomplished first with a simple gauge and regulator
with some electronics and a two-point controller. You would set your
desired end vacuum and allowable tolerance.”
A few years ago, the company launched its first-ever remotely
controlled wireless diaphragm pump system: the SC920. The usual
features of the KNF Neuberger diaphragm line were available, and
with this new system came four different operating modes: vessel
evacuation with adjustable pump capacity, constant pressure control,
automatic detection of a sample’s vapor pressure, and intelligent regu-
lation of process pressure using a user-defined pressure curve. But the
key innovation was a simplified wireless touchscreen and control knob
interface that could be used remotely.
Expanding its line of wireless controlled systems, KNF more recently launched a new speed-regulated pump system, the SC950. Improving on the SC920’s 20-L/min pumping capacity, the SC950 offers
50-L/min pumping. According to McDougall, the SC950 eliminates
what was once necessary for multihead pump systems—either placing
the heads in parallel to create faster flow, or putting them in series for
deeper end vacuum. With a newer design, the SC950 is able to provide
both high flow and a deeper end vacuum in a small package with low
The benefits of wireless remote control may not be obvious. However, utilizing wireless control eliminates many installation concerns.
The vacuum system can be placed under the bench, on a shelf, or
under a fume hood and controlled with the handheld unit, thus freeing up scarce benchtop space. Compared to the SC920, the newest
pump in the line is also a more efficient player even when located
on the benchtop. Though it is 2. 5 inches taller than the SC920, it is
just 9. 7 inches wide, nearly five inches narrower, thus saving precious
KNF Neuberger has not compiled statistics on how much energy
the use of a SC920 or SC950 pump system might save when used
regularly in a fume hood; but when operating in a sash-closed position, HVAC efficiency typically increases substantially. Another environmentally friendly feature of these pump systems is the revised
inlet/outlet condenser, which reduces solvent emissions.
The DC motor also contributes to efficiency. As opposed to AC
motors, the DC unit can be adjusted precisely by the controller, optimizing power consumption required to maintain the target vacuum
level. Such control also allows the operator to select a vacuum level
and walk away confident that the process will proceed as desired.
Sealing in the energy savings
Pfeiffer Vacuum is best known for inventing the turbomolecular pump
in 1958. But its experience in displacement pumps is even deeper. In