The Lee Company offers a wide selection of field-proven single and multiple orifice precision flow restrictors for a variety of demanding applications, including aerospace hydraulic and fuel systems, oil tools, race cars, and other sophisticated fluid power systems. Design engineers worldwide have found Lee Company flow restrictors to be indispensable when small size, light weight and proven reliability are required.
Lee Jets, High Watt and Kilowatt Jets, and the Lee Microjet are all single orifice restrictors. Lee High Watt and Kilowatt Jets handle low Lohm rates (high flow rates) while higher Lohm rates (lower flow rates) are covered by Lee Jets.
Lee Jets® (JETA Series)
Lee Jets are pre-calibrated, single orifice flow restrictors that are available in 0.156” and 0.187” diameter models. Offered in 87 standard Lohm rates, with tolerances of ± 2% and ± 5%, Lee Jets are easily installed into a manifold without the need for threads, seals, flow testing or filter screen design. Each Lee Jet is 100% tested and incorporates two integral safety screens for bidirectional flow.
Lee High Watt Jet (JEHA Series)
Lee Kilowatt Jet (JEKA Series)
Lee High Watt and Kilowatt Jets provide accurate, screened, bidirectional metered flow in the 90-1000 Lohm range. Due to their rugged construction, they can readily withstand the high power dissipation that is often associated with low Lohm applications. For instance, a 200 Lohm High Watt Jet dissipates 9.6 horsepower, or 7.1 kilowatts, at 3000 psi differential. Lee High Watt Jets are available in ±2% and ±5% tolerances and Kilowatt Jets in a ±5% Lohm rate tolerance.
Lee Micro Jets (JEMA Series)
Micro Jets are 100% calibrated flow restrictors designed specifically for flow balancing requirements in liquid cooling applications. Micro Jets are 100% flow tested, unidirectionally, to a ± 2% flow tolerance, and are protected by an integral safety screen. Micro Jets are sufficiently small to be easily installed in heat exchanger return ports or behind quick disconnect fittings.
The multi-orifice restrictors consist of Lee Bender Jets® and many different versions of the Lee Visco Jet®. Bender Jets employ several non-coaxial orifices in series using bending and multiple orifices to increase restriction. The Visco Jet adds the dimension of spin chambers for even higher restriction. Visco Jets range from small inserts all the way up to large cartridge versions, offering many options in minimum passage, Lohm rate and size.
Lee Bender Jets® (JEBA Series)
The Lee Bender Jets incorporate multiple orifices in series, with successive orifices on the centerline and displaced from it, to force fluid to “bend” 90° as it passes through the unit. The combined effect is an increase in the orifice size for a given Lohm rate. The orifices are bigger than a single orifice, but not as large as the passageways in a Lee Visco Jet. All units are protected with two integral safety screens for bi-directional flow, and are available calibrated to a ±5% tolerance in the 1900 to 9500 Lohm range.
Axial Visco Jets® (VXCA Series)
The Lee Axial Visco Jet also uses multiple orifices in series, but uses spinning to increase Lohm rate. Spinner discs alternately reverse the direction of spin of the fluid. The result is a larger passage size than a Bender Jet for a given Lohm rate but smaller than a Visco Jet. Rugged screens protect the orifice in both flow directions. Axial Visco Jets are available calibrated to a ±5% tolerance in the 680 to 11,000 Lohm range. Learn how the Axial Visco works.
Lee Visco Jets and Lee JEVAs provide the highest level of restriction with the largest minimum passage sizes in Lee’s line of precision flow restrictors. Lee Visco Jets are calibrated to restrictions up to 2,200,000 Lohms (an equivalent restriction of less than 0.0001” dia.). This is accomplished by the incorporation of several proprietary orifices in series, which force the fluid to both spin and change rotational direction. This results in a high level of restriction with a minimum passage size that is significantly larger than a comparable single orifice restrictor. The JEVA is a derivative of the Visco Jet design that provides a further increase in minimum passage size. All Lee Visco Jets and Lee JEVAs are available calibrated to a ±5% or ±10% flow tolerance. Visco Jets with minimum passageways of 0.032 inch or less are protected with two safety screens for bi-directional flow applications. Learn More about how the Lee Visco Jet works.
Cascade Restrictor Orifice: