Top quality lock nuts for critical joints 03 September 2015

For fifty years J. Lanfranco & Cie, headquartered in Paris, France, has been manufacturing self-locking slotted nuts with a reliability that it says is renowned in the rail and industrial sectors, when compared with locking by deformation nuts or nuts with inserts (nylon or metal).

J. Lanfranco’s dual slotted, self-locking system is superimposed on the nut body. The two slots are symmetrically opposite and perpendicular to the axis of the bolt. During manufacture the locking elements are deformed so that the slots are closed. When installed the slots open, engaging and exerting a clamping force on the bolt thread flank on opposite sides and in different planes, in this way self-locking according to ISO 2320. The self-locking nut will not damage the bolt and when removed the slots revert to the closed position allowing it to be reused at least five times without any reduction of its self-locking properties.
Withstanding vibrations, fluids, as well as low and high temperatures, this slotted design has been tried and tested across all industries including rail, national defence, compressors, wind turbines, nuclear power plants and lifting machinery. Due to this J. Lanfranco has adapted these locking systems for modular fixtures systems so that they can be modified to the specific needs of its customers.
These modular fixture systems include a stainless steel or aluminium alloy section that is cut to the requested length and in which the company incorporates moveable slotted self-locking nuts. When there are several nuts, the equidistance between them is defined according to the customer’s requirements.
The mobility of the nuts can be multidirectional depending on what they are being used for. With such modular fixture systems, the user not only gains time significantly during assembly, but also obtains the necessary tightening with just one part, and therefore avoids the build-up of different mechanical parts used beforehand.
These nuts can be put to a variety of uses: V-form plough on high-speed trains, window fasteners, door and leaf fasteners, seats, interior apparatus and structures, lift shafts, inserts, electro mechanics and cable pipework, as well as all applications subject to vibration.

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Will joined Fastener + Fixing Magazine in 2007 and over the last 15 years has experienced every facet of the fastener sector - interviewing key figures within the industry and visiting leading companies and exhibitions around the globe.

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