Continuous Improvement in MFCS Mundelein: Making a Good Machine Better

Uni-torque locknuts have been part of the MacLean-Fogg family for 60 Years.

In 1954, the Trademark “Uni-Torque” was filed and registered in 1955. In the beginning, a standard hydraulic Dennison press was used to produce the force that deflected the nut. Throughout the years, MFCS Engineering has designed innovative ways to improve quality and increase productivity.

In 1976, a team designed “high speed” presses. This technology was advanced for its time. The machine used hydraulics to produce the force to deflect the nuts, and air to return the cylinder. This resulted in production speeds of over 150 parts per minute. The high speed presses served the company well for 30 years.
Pressure to improve quality, aging equipment and advancement in hydraulic controls paved the way for a new way to produce Uni-Torque lock nuts.

In 2005, two engineers teamed up with a machine builder to design the next phase of deflection machine. With programmable logic controllers, and new hydraulic control boards, the company was able to control the machine with linear position sensors and pressure transducers.

In 2007, the design was improved with a monitor to give feedback and cycle the machine based on the force produced on the nut. This produced an extremely consistent locking feature. Unfortunately, the production rate was reduced due to the processing time of the controllers.

In 2011, an engineer from Metform took the baton. After visiting Mundelein, he met with hydraulic manufacturers and implemented a new control card. This produced a greater machine response time.

Today, MFCS is benefiting from the pioneers. Mundelein has recently purchased two new deflection machines. Building on prior advancements, MFCS is capable of running a greater range of nut sizes for each machine size. Using the capabilities of the control card, MFCS has the ability to control the speed and pressure of the hydraulic cylinder at speeds greater than 200 parts per minute. This has made a great impact on WIP inventory, improving throughput, and producing a high quality part at a competitive price.


The MacLean-Fogg Uni-Torque Locknut Anatomy


A.  Lock - At the top of the nut, allows nut to be threaded almost all the way onto the bolt before wrenching is required.

B.  Sizes - Finished, Heavy, and High Hexagon Dimensions, #4-40 thru 2", United Series, Class 2B and 3B, Metric sizes M4-M20.

C.  Thread Deflection - Inward and downward at two 180 degree opposing areas.  Unique shape and direction of deflection on this prevailing torque lock nut provide locking action on the entire flank, root, and crest of each thread producing extremely low scatter, reusable of 15 times or more and accurate predicion of tightening torques.

D.  Chamfered Top - Not only facilitates the addition of the locking element during manufacture, but also serves to identify "top" from "bottom" during fastener assembly.

E.  Material - "All metal" low and medial carbon steel are standard:  stainless steel, brass, and aluminum in any sizes.