Cermet Bushing A 40x50x25 for Front Travel Hubs

Cermet Bushing A 40x50x25 for Front Travel Hubs

The cermet bushing A 40x50x25 (GOST 2795-2001) is the primary sliding support element that ensures wheel base rotation in the modernized two-wheel front travel system of modern grain loaders in the ZM series (ZM-60U, ZM-90U, ZM-120U) and ZMB series; it can also be found on updated versions of classic ZM-60/60A models, replacing roller bushings. In the overall kinematic scheme of the assembly, these bushings are rigidly press-fitted into the cast-iron housing of the hub (ZPT 1007). Their primary engineering task is to absorb static and dynamic radial loads from the massive unit's weight while ensuring smooth rotation of the rubber-coated wheels on the mounting journals of the pendulum axle OVI 01.023 during travel and maneuvering across the threshing floor. A total of four such parts are installed on one modernized two-wheel front travel system — two bushings per hub.

The transition to using cermet sliding bearings was one of the steps taken by Zavod Moroza to strengthen and adapt the equipment's undercarriage to modern realities. In classic struts of previous generations, rotation was performed by standard roller bushings, which in practice proved too vulnerable to the specifics of threshing floor operations. Due to the inevitable ingress of abrasive grain dust and dirt into the assembly, the rollers wore out quickly, causing play and sometimes leading to complete wheel seizure. Conversely, the porous structure of cermet is better at retaining lubricant on the working surface and demonstrates significantly higher resistance to abrasive wear. Such a design excellently withstands constant static pressure and harsh impacts from concrete surface irregularities, making the support assembly maximally reliable and low-maintenance.

Technical Specifications of Cermet Bushing A 40x50x25

• Standard / Marking: A 40x50x25 according to GOST 2795-2001
• Inner working diameter: 40 mm
• Outer mounting diameter: 50 mm
• Length (width): 25 mm
• Material: Iron-graphite composition (powder mixture)
• Installation location: Wheel hub ZPT 1007
• Quantity for modernized two-wheel travel: 4 pcs.

The material for manufacturing this bushing is a special mixture of powders, pressed and sintered at high temperatures. Visually, the part has a characteristic gray color because it is iron-graphite cermet, not bronze — this choice of material is technically justified, as iron-graphite withstands high static pressure and harsh radial impacts from the massive machine frame significantly better. Thanks to its porous structure, the cermet works like a sponge — it is capable of absorbing and retaining grease (such as grease or Litol, which are injected via a grease nipple during maintenance). Combined with graphite, which acts as a natural dry lubricant, this creates a reliable anti-friction friction pair with the metal axle journal, preventing galling, overheating during towing, and other negative manifestations even in the harsh abrasive conditions of the threshing floor.

Given that many machines in operation have undergone years of "garage" modifications, mounting points in non-standard hubs often differ from factory sizes. For such cases, we have provided a flexible engineering approach to configuration, where we can select cermet bushings of other nominal diameters from our wide warehouse assortment if necessary.

Furthermore, the structure of these products allows for precise mechanical processing. For example, if your non-standard hub has a shallower mounting channel depth, we can perform end-trimming of the part on a lathe — this allows for perfect adaptation of the bushing length to your individual parameters, guaranteeing proper sliding bearing installation without protruding edges that would hinder the assembly of protective washers.

Special emphasis should be placed on the installation rules for this part: since cermet is formed using powder metallurgy, it possesses high hardness and abrasion resistance, but is sensitive to point dynamic impacts. Press-fitting the A 40x50x25 bushing into the cast-iron hub housing ZPT 1007 must be done exclusively using a hydraulic press or by tightening it evenly through a special guide mandrel. Direct hammer blows to the end of the part during installation are a gross violation of mounting technology and can lead to micro-cracks or cracking of the cermet before the unit even begins operation.

Related Components of the Rotation Support Assembly

Since the cermet bushing A 40x50x25 works as a sliding bearing in a closed system, the condition of the following adjacent parts must be checked during diagnostics or replacement:

• Wheel hub ZPT 1007
• Balancer wheel axle OVI 01.023
• Protective end washer ZP 01.020.001
• Grease nipple M10x1

In agricultural machinery from various manufacturers and generations, alternative solutions are often found in sliding assemblies, and a historically common variant is the use of classic bronze bushings (e.g., tin bronze like BrOTsS). While bronze does offer excellent resistance to impact loads and has a high coefficient of sliding, in the aggressive abrasive environment of the threshing floor, where fine grain dust constantly mixes with lubricant, iron-graphite cermet demonstrates significantly higher operational endurance. However, if your farm traditionally prefers bronze, or if the unit operates in specific conditions with increased impact loads, it is always possible to select or manufacture bushings of similar size from bronze alloys.

Cermet has high hardness but is sensitive to impacts during installation. As mentioned, self-press-fitting the bushing into a cast-iron hub in the field using a hammer or sledgehammer often ends with the new part cracking. The most rational and fastest engineering solution is to order the ZPT 1007 hub assembly, where the bushings are already factory-pressed using hydraulic equipment with the correct tension and perfect alignment — you will only need to mount the ready-made unit onto the axle and tighten the bolts. For units that have undergone non-standard garage modifications (e.g., installing axles from other machinery or altered journal diameters after machining), the standard factory bushing might not fit — in such cases, we have the capabilities to manufacture custom sliding bearings strictly according to your drawings or sketches. Our equipment allows for the rapid machining of non-standard dimensions from the required material to fit your machine's specific tolerances.

It is also worth remembering that bushings are parts subject to regular replacement, and due to their low cost and compact size, it is most rational to stock these consumables "in reserve." Having a backup set of bushings (or a ready-made hub assembly) right in the workshop will minimize grain loader downtime during the peak season, allowing the operator to conduct a quick unit replacement immediately upon detecting critical wheel play.

Buy Cermet Bushing A 40x50x25 from Zavod Moroza

This small iron-graphite part is a vivid example of how an inconspicuous detail determines the functionality of the entire massive unit. You can have everything else perfect, but without proper sliding on the axle, maneuvering the unit will turn into a constant struggle with harsh friction. At our enterprise, you can buy cermet bushings A 40x50x25 in any quantity needed — from a few units for a quick fix on the threshing floor to large reserve batches to fully equip your workshop once and for all.

We value every working hour of the farmer, so we approach orders more from an engineering perspective than a purely commercial one. Our specialists will listen to your problem and suggest the most rational path — simply sending basic consumables, machining a non-standard size for your modified axle, or providing a ready-made, perfectly press-fitted hub that will save the mechanic's time and stress. Order proven sliding bearings to return the wheel rotation to its original ease, which can reduce losses from unnecessary friction — after all, on the threshing floor, you need to work with grain, not fight with your own undercarriage.