Three static mixers: The top is an alternating spiral with each spiral offset by 90°; the second is the above in a delivery tube, such as for epoxy; the last is a larger metal mixer used to divide a flow into streams that intersect at 90°
A static mixer is a device for blending (mixing) two liquid materials. The device consists of mixer elements contained in a cylindrical (tube)or squared housing. The static mixer elements consist of a series of baffles that are made from metal or a variety of plastics. Similarly, the mixer housing can be made from metal or plastic. Typical materials of construction for the static mixer components included stainless steel, polypropylene, Teflon, Kynar and polyacetal.
The overall system design incorporates a method for delivering two streams of liquids into the static mixer. As the streams move through the mixer, the "non-moving" elements continuously blend the materials. Complete mixing is dependent on many variables including mixer length, tube inner diameter, number of elements and the design of the elements.
A common application for static mixers include mixing two component adhesives (e.g., epoxy) and sealants (See resin casting). Other applications include wastewater treatment, chemical processing, etc.