PRECISION MECHANICAL COMPONENTS

BEARINGS

Fuji bearing locknuts provide a secure way of locking bearings without the need for a keyway. They are suitable for thread sizes from M8X0.75 to M150X2. Bolt threads have to be to ISO965 medium quality.

FASTENERS

Bolted connections that are subjected to vibration usually require some form of lock washer. The patented Schnorr safety washer provides an effective means of securing bolted connections. These safety washers are in the form of a disc spring which is serrated on both sides and of trapezoidal section. Their inside diameters are matched to screw dimensions. The outer diameter of the washer is matched to the head diameter of pan-head and hexagon socket head cap screws. Schnorr safety washers are available in two series. The ‘S’ series is suitable for normal duty and available for screws of size M1.6 to M36. The ‘VS’ series is thicker and therefore achieves higher pretensioning loads. The inner and outer diameters are the same as for the ‘S’ series. VS washers are available for screw sizes M5 to M30. Apart from standard spring steel, both series are available in corrosion resistant steel and spring bronze CuSn8. Load washers are a type of locking washer that have been specifically developed for high-strength bolts 8.8-10.9 as per DIN ISO 898 Part 1 (SAE grade 5). Load washers for high tensile bolts maintain a sufficiently high pretension in the connection with the spring force. The HDS series are to DIN 6796 and screw sizes M2 to M30. Where a smaller outside diameter is required the HS series is available for screw sizes M6 to M30.

SEALS

Laminar seals are non-contacting seals providing a labyrinth seal for protecting grease lubricated ball and roller bearings in especially demanding applications. They are made from spring steel in the size range 15 to 1300mm nominal bore. Temperatures of up to 500C can be accommodated and in the case of rings for sealing axial compensators in internal combustion engines, temperatures of up to 700C. Fey rings can be adapted to produce custom made piston rings. Single and double wound retaining rings both internal and external in the size range 15 to 1300mm are also  produced. These are sometimes called circlips. A range of seals for protecting wheel bearings with ball or taper roller bearings is available. They are matched to the bearing outside diameter and are suitable for bearings of up to 150mm outside diameter. 

SPRINGS

Disc springs are sometimes known as ‘Belleville Springs’. The original inventor is not known but what is known is that Julian Francois Belleville of Dunkirk was granted a French patent in 1861 for a spring design which already contained the principle of the disc spring. The creation of the modern disc spring is largely credited to the efforts of Adolf Schnorr in the 1920s. Disc springs can be used as single elements or stacked in series or parallel to give a disc spring stack of accurate and predictable load/deflection characteristics. Standard sizes vary from 6mm to 250mm outside diameter. A wide range of materials is available for corrosion resistant to high temperature applications. Non magnetic applications can be accommodated using tin bronze to DIN 17670. Beryllium copper and nickel and cobalt alloys can also be used for arduous disc spring applications.

Special springs can be produced using the expertise of Schnorr including tool design and specialist heat treatment techniques.

OTHER PRODUCTS

Our range of precision ball screws have an extremely high transmission efficiency of over 90% compared to conventional Acme screws and as a consequence the required torque is reduced to one third or less. The axial clearance in the nut is accurately controlled and can, in fact, be eliminated by preloading with two nuts resulting in increased rigidity. Due to rolling contact very little wear occurs ensuring consistent performance over the life of the assembly. Nominal outside diameter of the screw shaft can vary from 3 to 40mm. Shaft length can be specified by the customer together with any special end features for location in bearings etc. Dust seals are available and can be fitted to each end of the nut.

Ground precision shaft, spindles and rollers are available in diameters from 0.2mm to 10mm in carbon chrome steel AISI 52100 and from1.0mm to 6mm in stainless steel AISI 420F. Shaft lengths from 6mm to 80mm depending upon diameter. All pins are centreless ground, lapped and polished. Special shafts within the above size range can be produced. Diametral accuracy is normally +/- 0.002mm but +/- 0.001mm can be achieved on request.