Stirring Bars and Rods
Products of various sizes, shapes, and material compositions designed to aid in manual or automatic stirring of laboratory solutions. Includes glass stirring rods, magnetic stir bars, and stir bar retrievers.
What Is a Magnetic Stir Bar?
Magnetic stir bars are stirrers or stirring hotplates used with magnets to mix a liquid or solution by creating a vortex.
A number of factors affect magnetic stir bar efficiency and effectiveness, including its size, shape, and material. Sizes (L x Diameter) range from 2 x 2 mm to 159 x 27 mm and shapes include:
- Polygonal or octagonal magnetic stir bars are the most common shapes; the multiple surfaces add turbulence to the mixing action
- Elliptical or egg-shapped stir bars work especially well with round-bottom flasks
- Wedge-shaped spin bars produce more significant turbulence for dissolving salts or in samples containing sediment
- Spin bars with fins or vanes, designed for smaller vessels, tubes, or cuvettes
- Micro (“flea”) stir bars for mixing extremely small samples
What Kind of Magnet Is Used?
Stir bar magnets are typically made from Alnico, a combination of aluminum and nickel. They may also be made from Samarium cobalt, a rare earth metal that produces the stronger magnetic force needed to mix very viscous substances.
Stir bar magnets are usually encapsulated in white or colored PTFE, hard plastic, or borosilicate glass, and coatings may meet FDA grade or USP requirements. PTFE is durable, inert, and can be autoclaved. Glass-encased cylindrical magnets are useful for high-temperature applications.
How Does It Work?
During the stirring process, integral or removable pivot rings on the stir bar reduce contact with the vessel to help avoid marring plastic surfaces. Some round stir bars have slightly raised ends that create a de facto pivot point, while others have more pronounced round centers that help to keep them in motion. Stir bars may be reusable or disposable.
Magnetic stir bars may be sold individually or in magnetic stir bar kits that include multiple bars in a range of sizes.
Cowie Technology Corporation OCTAHEDRAL STIR 64MM L 8MM D
This item has a minimum qty of 30 per supplier requirements.
Stirbar, octahedral, length 64 mm, diameter 8 mm
MSC US Cargo Control Polyester Ratchet Strap Tie Down, 27 ft, 2 in, Flat Hook
This polyester ratchet strap tie down is designed for securing cargo. It features a durable polyester strap and a flat hook end fitting, providing reliable load securement for various applications.
- Durable polyester strap
- 27 ft length
- 2 in width
- 10000 lb breaking strength
- 3333 lb load capacity
- Flat hook end fitting
- Steel end material
- Green color
- 1 ft fixed end length
MSC Mag-Mate Lift Magnet, 250 lb Capacity, Permanent, On/Off Handle, 2 Poles
This permanent lift magnet offers a 250 lb capacity for handling flat objects. It features an On/Off handle for activation and has two poles, making it suitable for various lifting applications.
- Permanent magnet type
- On/off handle for easy activation
- Maximum load capacity of 250 lb
- Two poles for effective lifting
- Includes a 3 inch ceramic magnetic retriever
- Designed for use with flat objects
- Overall length: 5 inch
- Overall width: 2.63 inch
- Overall height: 2.625 inch
MSC Industrial Magnetics, Inc. Lift Magnet, 220 lb Capacity, Permanent
This permanent magnet lift is designed for lifting round and curved surfaces such as shafts, thick-walled pipe, or billet, with the ability to also handle flat materials. It features specially designed pole shoes that provide a deep penetrating magnetic field and part stability, offering a 220 lb working load limit.
- On/off rare earth permanent magnet
- Handle requires only 90 degree rotation and locks at both on/off positions
- Durable, recessed metal nameplates
- Corrosion-resistant, plated magnet surface
- Heat resistant up to 180°F (82°C)
- 3:1 design factor
- Meets ASME B30.20 BTH-1 Design Category B, Service Class 3