Plain bearings

ZFO-P© - sliding materials

ZFO-P© represents a protected steel plain bearing brand with excellent sliding-tribological properties under mixed-friction conditions.
The sliding material, a special Fe-C-N composite material underwent several heat treatments, is based on a fine-grained, micro-alloyed steel matrix with a high compression yield point.
The firmly embedded and finely dispersed hard materials are resistant to a wide range of abrasives. A low-maintenance operating mode – with savings regarding more expensive, environmentally compatible greases - is often possible.

Particular sustainability aspects: Download our publication "Maschinen und Technik"

ZFO-P bushings are a sustainable substitute for bronzes and brasses.
Due to its enormous consumption of resources in mining and production, copper alloys have a comparatively heavy “ecological impact”.
The toxic effect of copper-bearing materials compared to microorganisms (biocenosis) with Cu contents exceeding 60 % is of current importance. The sliding wear particles of bronze and brass bushings from building machinery and grab bearings are resulting in a serious impairment of our ecosystems. The increasing demand from the electromobility and the alternative power generation will lead to a further shortage with considerable price jumps of copper, tin and zinc.

Therefore, a dissipative use of the superior conductor material Cu in oscillatively operated friction bearings is no longer appropriate because of alternative steel-sliding materials from a business-management and economic point of view.

ZFO-P

The plain bearings of the ZFO-P steel brand

have a high wear resistance to adhesion, abrasion and surface fatigue
are highly resistant to static and dynamic stress
have a low-friction, corrosion protective overlay with rhomb groove structure
are heat-resistant up to 500°C
need less lubricants than bronze and brass bushings etc.
are an ecological and cost-efficient replacement of Cu alloys

ZFO-Psmart

The geometric modification of the whole sliding surface with fine “smart” rhomb groove structures achieves a minimization of the friction coefficient. The proportion of the fluid friction is increased. The local tribological stress is considerably reduced so that the service life - with simultaneously smooth operating mode - increases. The smart technology is favourable if specific requirements on a minimum integral friction force are imposed combined with grease lubrication of sufficient viscosity.

ZFO-Psplit

Wrapped steel bushes, e. g., of spring steel or Cu alloy which, are joined in rough housing seats according to H9/H10/H11 can be substituted by this fully cylindrical designwith elastic adjustment to the housing bore. Thus, the high wear resistance of ZFO-P steel sliding materials can also be used in such cases of application in a cost-effective way – without changing the fitting accuracy.

ZFO-Pniro

This rust-proof version allows the use combined with the requirement on a high corrosion resistance, e. g., in seawater environments. Due to vacuum-supported heat treatments of appropriate steels and diffusion techniques, resistant structures against the specific application-oriented and specifically acting wear mechanisms are assembled.
Regarding geometrical aspects, different corrosion-proof cylindrical plain bearings and/or spherical plain bearings with defined hardness gradients from inner and outer ring can be manufactured to achieve an optimized hardness gradient.

Counter bodies in the tribological system with ZFO-P plain bearings

The axle/wave counter bodies should consist of induction hardened heat treatable steels or of case-hardened or carbonitrided steels.
Through-hardened axles made of tough rolled or cold work steels are also possible, if a hardness of 57-58 HRC can be achieved.
Martensitic chromium steels, in individual cases with nickel and/or molybdenum additions are suited as corrosion-proof axles. A chromium layer on surface hardened heat treatable steels is often sufficient.

Application areas

Bearings in joints of wheel loaders
Conveyor equipment for container stripping/undercarriages
Crane joints | jib bearings
Cylinder pivots
Bearings in shipbuilding
Lifting gear bearings | gripper joints
Excavator joints | jib bearings | mining equipment
Tractor joints | accessory equipment | spring suspensions | steering linkages
Replacement of various bronze bearings in joints of the steel, cement, aluminium industry