NEN 400003 Bushing

NEN 400003 Bushing (NEN 4.00.003)

The NEN 400003 bushing is a specialized sleeve bearing that plays a critical role in the kinematics of various assemblies in grain throwers, grain cleaners, and other agricultural machinery. Unlike most parts machined from conventional steel stock, this bushing is manufactured using advanced powder metallurgy technology (sintering of cermet/powder-metal mixtures). This material features a unique fine-porous structure capable of storing and retaining lubricant, ensuring a minimal friction coefficient and high wear resistance even under significant radial loads.

Technical Specifications of the NEN 400003 / 4.00.003 Bushing

• Catalog number: NEN 4.00.003 (or NEN 400003)
• Part type: Cermet (powder metal) sleeve bearing
• Inner diameter (shaft fit): 30 mm
• Outer diameter (housing fit): 40 mm
• Length (width): 20 mm
• Material: Powder mixture (cermet / porous metal)
• Weight: 0.062 kg

Agricultural machinery operates in highly dusty environments where applying grease regularly is often inconvenient. This is precisely where cermet material demonstrates its primary engineering potential—self-lubrication. Thanks to the porous structure, the bushing acts like a durable sponge soaked in oil. When the shaft begins to rotate and the assembly heats up from friction, oil rises to the working surface due to capillary action and thermal expansion, forming a stable protective film. As soon as rotation stops and the part cools down, the oil is re-absorbed back into the pores. This characteristic guarantees smooth shaft sliding without binding, even under irregular maintenance schedules.

In addition to facilitating smooth sliding, this bushing serves as a reliable mechanical fuse. Within the kinematic chain, it acts as the designated element that absorbs primary operational loads and wear. During critical overloads or abrasive contamination, the softer cermet bushing wears out instead of the expensive steel shaft or the massive cast-iron housing of the hub or gearbox. Its dimensions of 30x40x20 mm represent an extremely popular standard for power transmissions across many agricultural machines, as it fits any 30 mm shaft—whether ensuring free wheel rotation, providing safe slip protection within safety clutches, or supporting moving elements in self-propelling gearboxes. Economically, replacing this intermediate component is far more efficient than overhauling or replacing worn axles and hubs.

Application Assemblies for the NEN 400003 / 4.00.003 Cermet Bushing

Due to its unique anti-friction properties and standardized dimensions (30x40x20 mm), this part is widely utilized in the kinematic schemes of various agricultural machinery. Most frequently, the bushing is found in the following assemblies:

• Drive wheel hub ZM 01.180 (Rear drive assembly ZP 01.220)
• Loading conveyor safety clutch ZP 02.050
• Self-propelling gearboxes (shaft support assemblies driving the running wheel chains on OVS grain cleaners and ZM grain throwers)

Within the running gear of classic and modernized grain throwers, the bushing functions as the main sleeve bearing for the driving wheels. Two such cermet parts are press-fitted tightly into the central smooth bore of each cast-iron ZM 01.180 hub. Their function becomes apparent during equipment transport: when the operator pulls the jaw half-clutch back to break the kinematic connection with the gearbox, the hub is forced to rotate on the stationary half-axle. These porous bushings allow the heavy wheel to roll freely and without binding along the 30 mm steel shaft, completely unloading the transmission.

The loading conveyor utilizes a friction safety clutch ZP 02.050, which protects the mechanism from damage in the event of chain jamming or foreign objects entering the loading intake. Two NEN 400003 cermet bushings are also installed inside this assembly; when operating loads exceed the permissible torque threshold (calibrated by springs at 160 Nm), the friction plates disengage. At this moment, the bushings ensure safe slippage of the drive sprocket around the shaft, preventing chain breakage or subsequent transmission failure.

Another major application zone is two-speed self-propelling gearboxes (standard for OVS grain cleaners and installed on modern modernized grain throwers). The kinematics of this assembly involve transmitting torque from the gearbox output shafts to the running wheel axles via chain drives. Because a tensioned drive chain creates continuous heavy radial loads, the output shafts require reliable support. The cermet bushing handles this role exceptionally well, centering the shaft within the housing and withstanding significant pressure from the chain drive without requiring constant grease gun lubrication, thanks to its self-lubricating effect.

Buying the NEN 400003 Cermet Bushing from Zavod Moroza

Using original sleeve bearings is the cornerstone of longevity and stability for any moving mechanism. Deciding to purchase a cermet bushing from Zavod Moroza ensures you receive a part with the correct micro-porous structure, guaranteeing a self-lubricating effect and robust protection for steel shafts. However, it is essential to keep a key technological nuance in mind: installing such elements requires utmost care. Cermet materials are highly sensitive to impact loads during installation and must never be hammered or driven in with makeshift drifts. Precise, smooth press-fitting using a specialized hydraulic press is necessary to avoid geometric distortion, edge chipping, or collapsing the material pores.

Understanding these practical repair challenges within farm workshops, we offer the most reliable solution. You can order not only individual replacement bushings but also fully pre-assembled components and assemblies. Under factory conditions, we perform professional press-fitting of cermet parts using hydraulic equipment with precise positioning, guaranteeing an ideal fit, correct coaxiality, 100% preservation of anti-friction properties, and the formation of a proper free internal chamber directly opposite the grease fitting for unobstructed shaft lubrication.

Contact our sales department for technical consultation and order processing. Choose high-quality components or fully assembled units, parts, and mechanisms directly from the manufacturer to swiftly restore your agricultural machinery's performance and ensure long-term, trouble-free operation!