Bracket ZP 01.421 (Self-Propulsion Gearbox of ZM-60/60A)

Bracket ZP 01.421 (Self-Propulsion Gearbox of ZM-60/60A)

The ZP 01.421 bracket is a steel load-bearing element of the lower frame for classic ZM-60 and ZM-60A series grain loaders. A single unit is factory-equipped with two such brackets, which are symmetrically attached to the longitudinal beams of the main frame. Their engineering purpose is to securely hold the central gearbox (the ZP 07.000 self-propulsion mechanism), the assembled operating weight of which is nearly 69 kg.

Structurally, the part weighs 1.87 kg (manufactured from durable St. 3ps steel) and serves as a reliable support with a characteristic U-shaped cutout — a saddle. The protruding elements of the gearbox housing rest in this groove, supported by the bracket through their mass. This specific type of mounting is a technical necessity, as it allows the massive gearbox to be perfectly centered relative to the rear wheel base for correct and uniform tension of both drive chains. In addition, this type of seating allows the assembly to partially absorb operational vibrations and compensate for micro-misalignments of the frame as the machine moves over uneven threshing floor surfaces.

Technical Specifications of Bracket ZP 01.421

• Catalog number: ZP 01.421
• Application: Classic ZM-60 and ZM-60A grain loaders
• Manufacturing material: St. 3ps steel (in accordance with GOST 14637-79)
• Product weight: 1.87 kg
• Quantity per unit: 2 pcs.
• Mounting type: Bolted connection to the longitudinal beams of the lower frame

Structurally, the part is a massive steel element with a characteristic U-shaped cutout — this cutout acts as a technological saddle into which the protruding axes of the heavy central gearbox directly rest. Due to the absence of a rigid welded seam, this mounting allows the mechanism to be precisely centered relative to the rear axle of the wheels to ensure proper tension of both drive chains.

The specificity of such open resting is dictated by the need to neutralize operational mechanical loads, where vibrations and misalignments of the main frame inevitably occur during the movement of the massive unit over uneven threshing floor surfaces. The bracket partially compensates for these, allowing the gearbox housing to safely maintain its position within the mounting slot.

Analyzing the architecture of modern modernized grain loaders by Zavod Moroza (ZM-60U, ZM-90U, and ZM-120U series), it is worth noting that the ZP 01.421 bracket is no longer used in their undercarriage. The new frame kinematic scheme is well-balanced and operates without the need to support a separate 70-kilogram intermediate gearbox in the center of the unit; therefore, our modern machines operate stably and smoothly without the use of these supporting mounts.

Related Parts and Configuration Options for the Self-Propulsion Assembly

Since the ZP 01.421 brackets function exclusively as paired load-bearing supports, they do not contain complex internal components, but they directly contact and work in tight coordination with the central drive parts. For the full maintenance of this assembly on a classic frame, you may need the following adjacent elements:

• Self-propulsion mechanism ZP 07.000 (travel gearbox)
• Roller drive chains
• Sprockets
• Speed control linkage (for ZM-60A)
• Fastening hardware

The main mechanism held by these brackets is the self-propulsion gearbox itself. Given the long history of production and modernization of classic grain loaders by various enterprises, several design variations of the mechanism could have been installed on old frames into these supports:

• Classic Large Gearbox
  The most common basic massive housing (weighing about 69 kg), which served as a simple distributor of rotation from the main engine to the wheels.
• Two-Speed Gearbox
  An improved modification that allowed the operator to use a lever to choose between a slow working speed (for the loading process) and a faster transport speed for moving across the threshing floor.
• Two-Speed Gearbox with Differential
  The most advanced version of the classic gearbox, which, in addition to speed selection, provided force distribution between the right and left wheels, significantly improving maneuverability and handling when turning without wheel slip.

Despite the fact that ZP 01.421 brackets and their corresponding old gearboxes are still widely used on threshing floors, in modern practices of overhauls and modernizations, farms often abandon this bulky system. In the architecture of new machines (such as the ZM-60U/90U/120U), Zavod Moroza is transitioning to compact and efficient motor-reducers, where the electric motor and gear transmission operate as a single unit. Such a modern assembly features a fundamentally different, much simpler mounting and chain-tensioning scheme. Accordingly, when retrofitting an old grain loader to a motor-reducer system, the need for the massive U-shaped ZP 01.421 brackets is eliminated — they are simply dismantled. However, if you are performing an authentic restoration of a classic ZM-60 and wish to preserve the factory single-motor setup, these brackets remain completely indispensable load-bearing parts that hold your 70-kilogram gearbox in place.

Buy Bracket ZP 01.421 or Switch to Modern Standards?

At Zavod Moroza, you can order ZP 01.421 load-bearing brackets for the overhaul of classic ZM-60 grain loaders. We manufacture these parts in strict compliance with the precise geometry of the U-shaped saddle, which guarantees the correct seating of the massive gearbox. This is critical for accurately centering it relative to the rear axle and avoiding misalignment or slipping of the drive chains while the machine is in motion.

However, if your old central gearbox has completely exhausted its working resource and requires constant maintenance, we recommend switching to modern engineering standards. Instead of restoring the bulky 70-kilogram kinematics of past generations, we can help completely retrofit your unit's undercarriage with newer, more efficient travel gearboxes or compact motor-reducers. Such assemblies, which feature a much simpler and more modern design (incidentally, without using supporting brackets on the frame or other adjacent parts), are standard equipment on our new ZM-60U, ZM-90U, and ZM-120U grain loaders.

Contact our technical department — we know the architecture of machines across all generations down to the smallest detail. Our specialists will help you select durable authentic parts for a classic repair or offer ready-made modern assemblies for a complete modernization of your equipment, permanently relieving you of problems with outdated mechanisms.