Laboratory Shaker Definition
The laboratory stirrer is designed to mix volumes ranging from 1 to 50 gallons. Industrial applications for a laboratory stirrer can include a variety of laboratory environments, chemicals, cosmetics, foods, coatings and many more. Innovative equipment such as the laboratory stirrer is an essential addition to modern laboratory technology.
The use of the laboratory stirrer is a great convenience when it comes to research and development, clinical research, education laboratories and a wide variety of other uses. This is largely due to the fact that our laboratory stirrer is designed and built to be easily operated with a robust capability to handle continuous use. Most laboratories require a compact design for their laboratory stirrers. Other benefits of laboratory stirrers include the ability to easily fit into smaller spaces and can be easily moved between laboratories or classrooms.
History and Origin of the Laboratory Shaker
The first laboratories relied on manual agitation to promote chemical reactions and other processes. However, in the early 20th century, the first dedicated laboratory stirrers were introduced to relieve researchers of this task, allowing for more controlled and prolonged stirring and agitation.
1910 a 1940
The first hot plate agitator was patented in 1917 by Richard Stringham of Utah and consisted of stationary electromagnets integrated into a hot plate base. When a reaction vessel, such as a flask or beaker, was placed in the stirrer, a bar magnet placed in the solution would spin as a result of the magnetic field created by the electromagnets.
A major problem in early 20th century research was the risk of fire due to the need to heat solutions using a naked flame. This problem was solved in the 1930s by husband and wife team Glen and Ruth Morey, who invented the heating blanket, a reliable, non-flammable heating device with electrical resistance wires woven into a fiberglass fabric jacket.
The first heating blanket was sold in 1939, and the couple formed the Glas-Col Apparatus Company to manufacture their new product. Although not an agitator, the heating mat represents an important stage in the development of heating systems often used with an external agitator.
It was found that the bar magnet used with early magnetic stirrers was less than ideal, particularly because the iron in the magnet could react with chemicals in solution and change the course of a reaction. To address this problem, two inventors working independently devised the coated bar magnet, which was chemically inert and did not participate in the ongoing reaction.
In 1944, Arthur Rosinger of Newark, New Jersey, received a patent for a coated magnetic stirring bar that was chemically inert. Rosinger’s stirring bars were coated with plastic, glass or porcelain and the stirrer itself had a rotating magnet instead of electromagnets at the base of the mixer.
A very similar device was designed independently by Edward McLaughlin of Greenock, Scotland in the late 1940s, apparently without knowledge of the earlier invention. Dr. McLaughlin coined the term «flea» to describe the stirring rod because of the way it would jump erratically in the flask if the magnet rotated too fast. The use of the term «flea» to describe a stirring bar persists to this day.
In 1949, graduate students at Rutgers University were frustrated in their attempts to isolate antibiotic-producing bacteria to treat infection by the frequent failure of their shaking apparatus. David and Sigmund Freedman at the newly formed New Brunswick Tool & Die Company offered to build a more effective shaking device, creating the first New Brunswick Shaker. The New Brunswick Shaker was later used in the isolation of Nobel Prize-winning streptomycin, creating an instant commercial demand for this instrument.
In 1950, IKA founders Curt Janke and Max Kunkel demonstrated their first magnetic stirrer at the first post-war ACHEMA exhibition. In 1959, two brothers, Jack A. Kraft and Harold D. Kraft, working for Scientific Industries, applied for a patent for the first vortex mixer. During the 1960s, numerous agitators and stirrers came to market, due to demand from scientists involved in cutting-edge research.
In 1964, the company launched the Vortex-Genie, an updated version of the Vortex Jr. Mixer, which became the standard mixing apparatus and the «workhorse» of many laboratories. The Vortex-Genie is the predecessor to many of today’s vortex mixers. In 1965, the static mixer was invented by C.D. Armeniades and colleagues at the Arthur D. Little Company. A static mixer mixes fluids creating fluid or laminar flow through a series of fixed helical elements enclosed within a tubular housing.
In 1970, Kuhner began manufacturing its first series of large capacity incubator mixers, known as the IRC-1 range. This innovation made it possible to mix samples under highly controlled conditions of temperature, humidity and CO2 concentration. In 1972, Salvador Bonet of the SBS company revolutionized laboratory stirrers with the concept of multi-point magnetic stirring, allowing different solutions to be stirred simultaneously for the first time under identical conditions.
1980 y 1990
During this period, NBS developed the world’s first microprocessor-controlled shakers, the Innova® range, which marked the beginning of the use of microchips to precisely control equipment set points, alarms, operating time, speed and temperature. Other innovations during the 1980s and 1990s included Kuhner’s first series of shaker cabinets (ISF-4) in 1981, followed in 1989 by its first stackable incubator shakers (ISF-1). Stackable shakers allowed several units to occupy the same floor space as a single unit, providing a space-saving option for laboratories.
In 1991, Kuhner introduced its first series of shaker rack systems, a space-saving device that allows several units to operate independently. In 2000, NBS added to its Innova range with the Innova 4200/4230 and Innova 4400/4430 high-capacity workbenches that used dual temperature programming to automate the changeover between two temperatures in a programmed manner.
In 2008, Grant Instruments responded to the need for platform shakers capable of withstanding harsher experimental conditions with the launch of its heavy-duty multifunctional orbital shaker. This shaker provided orbital motion, reciprocity and vibration functions, all in a single instrument controlled by a microprocessor. Also this year, Radleys devised a cost-effective way of removing up to six round-bottomed flasks simultaneously without the need for purging using a dedicated multiple shaker, through an additional module known as
In 2009, VELP Scientifica introduced its Vortex WX system which starts vibrating automatically when a sample is inserted, using infrared to detect the presence of the test tube. In 2010, Johnstown, PA ITSI Biosciences responded to the growing need for compact instrumentation by launching the small, lightweight ITSI Vortex Mixer and ITSI Magnetic Stirrer. Both instruments are battery operated, making them easy to move around the laboratory and ideal for use in the field.
In 2011, Scientific Industries developed a Vortex Mixer specifically for applications that require more aggressive action than can be achieved through the standard vortex. Finally, also in 2011, Grant Instruments launched the GLS Aqua Plus series of linear agitation baths that they developed specifically to meet the needs of molecular biologists in applications such as hybridization, production of bacterial culture media and for solubility studies.
What is the Lab Shaker ?
Laboratory shakers are instruments that help to form a homogeneous mixture from more than one ingredient. Used in many types of industry, such as food and beverages, cosmetics, pharmaceuticals and electronics, as well as in laboratories dealing with life sciences, wastewater treatment and biotechnology, agitators are an important part of many laboratories.
Laboratory stirrers do exactly that: stirring the mixtures placed in them. The plates vibrate back and forth or circularly to mix the components. Some laboratory stirrers have plates that tilt up and down as well as side to side for an additional mixing element.
What is the Laboratory Shaker used for ?
Laboratory shakers commonly refer to vortex mixers that are used to mix small liquid vials. An electric motor causes a rubber cup containing a test tube or other container to oscillate, causing the liquid inside to rotate. Agitators can also be overhead devices from which an agitation probe points downward into a fluid held in a vessel.
Use of the Laboratory Shaker
An agitator is one of the simplest and possibly most useful pieces of equipment in the laboratory. However, improper use of these units could be detrimental to their application. In addition, improper maintenance could lead to poor results and a shorter life for your machine.
- Use the right machine for your application
An agitator is not always the best tool for mixing. Even when it is, it is important that you choose a machine with sufficient power and select the right impeller, paddle or blade for your application. Of particular concern are high viscosity samples. Whether they have a high viscosity to begin with or become so during processing, mixing these materials could strain your mixer’s drive motor.
This causes it to overheat and wear more quickly, reducing the life of your machine. Some agitators have a feature that reduces power if a certain level is reached. It uses a «best effort» feature to maintain a particular stirring speed, even under a heavy workload. However, it can determine whether the work becomes harmful and, if so, will stop stirring.
Another feature of this machine is a small internal fan that can help prevent the motor from overheating. Other agitators have a red warning light that indicates when it is overloaded. Regardless of these measures, it is best to use the right tool for the job first. For example, for certain applications, you may need to consider a more powerful mixer, a different impeller or paddle, or a different type of machine, such as a homogenizer. Factors to consider include the solubility of the sample components, the desired particle size, and the viscosity of the sample.
2. Make sure the mixer is mounted correctly
The agitators are typically mounted on a pole attached to the laboratory bench or on their own separate stand. It is important to ensure that the mixer is mounted correctly to prevent it from sliding down and damaging the sample or causing injury. Vibrations caused by the mixer, especially when running at high speeds, can cause the clamps to loosen slightly, so they should be tightened before each use.
In some cases, the weight of the mixer resting against a clamp may make it appear to be firmly in place, even when it is not. As such, it is a good idea to try moving it at a few different angles to verify that it really is firmly in place. Make sure the impeller is locked in place
In addition to making sure that the mixer clamps are tight, you should also check that the impeller is locked in place inside the agitator chuck. On most models, the chuck clamps close around the impeller shaft when a key is turned. While locking the impeller in place, it is important to try to hold the center shaft so that the jaws close evenly. Otherwise, it may appear that the impeller is locked in place, even when it is not.
Then, once you start mixing your sample, the motion will cause the impeller to fall off, which could break your glassware, ruin your sample and create a safety hazard. Certain stirrers, such as Heidolph’s Hei-Torque value, have an audible signal to confirm that the impeller is set correctly. One way to avoid this is to close the gap between the jaws so that it is a little larger than the size of the impeller shaft before inserting the impeller. You can also turn the machine on to get a full view of the closure.
One more thing to check is that the impeller blade is firmly attached to the end of the shaft. These can loosen over time and come off while mixing. This is especially common when mixing very viscous materials. A quick squeeze with the proper tool before use should help avoid this problem.
3. Clean the unit regularly
The main part of the agitator housing the motor should be cleaned regularly with a soft cloth and a solution of warm water with a standard laboratory detergent. Even if sample splashes do not end up in the housing, they will tend to accumulate dust and dirt from the laboratory environment. Dust in particular can be disturbed by vibrations when the mixer is in use, and can cause your sample to become contaminated.
The impeller should be cleaned between each use to ensure that there is no cross-contamination between samples. If your mixer comes with a protective cover for the mandrel, you should use it. This will prevent corrosive materials from entering the machine, which will help prolong its life.
How Does the Lab Shaker work ?
- The magnetic stirrers use a rotating coated magnet to perform the stirring action on flasks and beakers. The vessel is placed on the magnetic stirrer plate under which a rotating motor-driven magnet causes the magnet in the sample vessel to rotate in the same manner.
- Hot plate magnetic stirrers allow researchers to provide a controlled amount of heat to the sample in 500°C increments, depending on the model.
- They also control the speed of the stirring action at 1600 RPM and the duration of mixing before shutdown. The operating parameters are programmed into the magnetic stirrer with the set and actual values shown on the LED display.
- Most hot plate magnetic stirrers are equipped with built-in safety features to protect against overheating, hot plate failure and other malfunctions.
- Optional Pt100 temperature sensors take control of the mixing function, monitor the action and shut down the equipment if inconsistencies are detected. An RS232 interface is available on certain models to collect the date of operation for record keeping.
- Because they are powered by magnetic energy rather than a direct connection to the motor, magnetic stirrers are not efficient for high viscosity samples.
The Overhead Stirrer
- The overhead stirrers are operated by a drive motor fixed to an adjustable stand.
- The mixing tools, also known as impellers, paddles and blades, are attached to a steel rod of sufficient length to immerse the tool at the required depth in the sample cup. The upper end of the rod is inserted and pressed into the chuck of the mixing motor.
- Overhead stirrer motors can be specified by the torque power required to work with viscosity based samples and by the speed and duration of stirring.
- Self-test functions will shut down the equipment in case of overheating or a sample viscosity that exceeds the limits of the unit.
Characteristics of the Laboratory Agitator
Given in revolutions per minute (rpm), this will vary by model. Most laboratory stirrers provide a speed range, such as 12-1800 rpm or 40-6000 rpm, but there are some single speed options. Check what speeds are needed for your process and stirring purpose. A digital speed display is an advantage if accuracy and repeatability of speed is needed.
The volume capacity of the agitator must reach or exceed the maximum batch size. The volumes can be 2 L, 25 L, 200 L and anywhere in between. The maximum volumes generally assume the viscosity of the water unless specified by the manufacturer.
Torque is the rotation force used to turn the impeller, commonly reported in Newton centimeters (N ∙ cm) or inch ounces (in-oz). The higher the torque, the better the agitator can sustain the rotation of the impeller in higher viscosity mixtures and when using larger diameter impellers.
This refers to the dynamic viscosity, which is the «thickness» of the fluid when it is agitated. It is an important factor for agitators mixing batches with viscosities greater than water, or viscosities that change during mixing.
A higher viscosity mix will require more agitator motor torque, and you want to make sure that your agitator can maintain its rpm under changing viscosity conditions. There are numerous features that may be important for your installation and application. Agitator chucks have a range of diameters, so make sure that the impeller shafts fit into the chuck.
Agitators with through shafts make it easy to adjust the impeller to an optimal height in the vessel, and even provide an easy way to move the impeller up for quick changes in mixing vessels. Reversible models offer both clockwise (standard) and counter-clockwise agitation. Other features to consider are digital display of torque and speed, zero torque, timer, lightweight and programmable mixing including automatic shutdown, data logging and external computer control.
Types of Laboratory Shakers
There are a variety of stirrers available for laboratory use, each with its own qualities that make them more suitable for certain applications than others.
Below is a summary of the types of stirrers available and what they are best suited for:
Magnetic stirrers use a rotating magnetic field to make a stirring rod (flea), immersed in a liquid, spin and therefore shake. Most magnetic stirrers are suitable for small volumes of low viscosity. However, there are some models that have been developed to handle large volumes and high viscosity. Magnetic stirrer plates are usually made of ceramic or stainless steel.
Ceramic Laboratory Stirrer
The ceramic top heating plates have excellent chemical resistance. So they are ideal if you are working with corrosive chemicals that can splash on the surface of the plate, and the white surface also means they are good for appraisals or other work where clear visibility of colour is essential.
Stainless Steel Agitator
A stainless steel top plate does not produce eddy currents (like aluminium) and therefore guarantees a very powerful coupling and stirring action.
Agitator Heating Plates
Stirring heating plates are stirrers combined with a heating plate. Any of the functions can be used alone in combination with each other. The main difference in the variety of stirring plates is what material the top plates are made of:
Overhead stirrers are generally more robust than magnetic stirrers and consist of the stirrer, rods, paddles and supports. They are most commonly used for large volumes and viscous solutions. The variety of paddle types can be used for different applications, as they create different stirring movements:
Low to medium speed, smooth mixing for minimum turbulence. Tangential flow.
Centrifugal Laboratory Agitators
Medium to high speed, used in round boats with narrow necks. Creates axial flow.
Medium to high speeds, used to draw the material to be mixed from above. Minimum cutting forces. Less risk of injury to operators when the agitating elements make contact with the vessel. Creates axial flow.
Medium to high speeds. To draw the material to be mixed from the top and bottom. High turbulence, high shear forces, particle reduction, radial flow.
Medium to high speeds. Efficient flow design with minimum shear forces. Draw material from top to bottom, axial flow.
Low speeds. Ideal for high viscosity liquids; tangential flow.
Sealed agitators that are suitable for immersion in water or oil and can be used with a wide temperature range. Ideal for use in water baths, ovens or incubators.
Designed specifically to agitate biological samples such as cell cultures. They provide gentle, heatless stirring and are dust and germ proof.
Laboratory Shaker Price in Euros
Industry 500W Laboratory Agitators, Magnetic Laboratory Stirrer Magnetic Plate Heater Agitation, MAX 3L For Liquid Lab Mixing Heater. Price: 281,50
Laboratory Stirrers Magnetic Stirrer IP54 Waterproof Magnetic Stirrer, 12500 Rpm Speed, For Liquid Lab Mixing Heaters Price: 477,45
Laboratory Stirrers, Small Laboratory Magnetic Stirrer, For Mixing Heaters Price: 94,04
Who Invented the Lab Shaker?
The first hot plate agitator was patented in 1917 by Richard Stringham of Utah.
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