Hydraulic motors are known for transmitting extremely high torque from a small package. However, they still contain shaft seals that must be protected from damage to avoid premature failure. Common consequences of seal failure are fluid leakage and ingression of contamination. Even if a seal is protected from hostile environments, another mode of failure is shaft deflection.
Deflection of a motor shaft causes it lose concentricity with the seal gland in the motor housing. This eccentricity widens the gap between the shaft surface and seal face, casing leakage. This same deflection also causes a narrowing of the gap 180 deg. away, which can lead to rapid wear of the seal.
An overhung load adapter ensures a stable mounting platform and increased bearing support on the distribution manifold between the hydraulic motor and the impeller/blender in this manure injection implement.
Worse still, radial load far exceeding the manufacturer’s recommendation can eventually lead to failure of the shaft bearings, and even fracturing of the motor shaft in extreme cases. Strong shaft bearings can help prevent deflection, but because hydraulic motors are often designed to be so compact, bearings may be rated only to minimal radial-load capacity.
Overhung load adapters address both of these potential issues by providing an extra level of contamination protection for the shaft seal, and dramatically higher load capacity for the shaft and shaft bearings.
As an example, a manufacturer of agricultural equipment designed a manure injection implement and specified overhung load adapters from Zero-Max Inc., Plymouth, Minn. Operating over plowed fields, manure injection equipment provides benefits over dry-fertilizer application systems, primarily because they inject nutrients directly into the soil directly at the depth and time of root formation. Manure injection also improves crop growth and reduces fertilizer runoff. No wonder manure injection systems have undergone impressive growth among farmers.
Overhung load adapters protect hydraulic motor bearings from unforeseen side loads and help prolong the life of seals by maintaining precise shaft alignment and shielding shaft seals from hostile ambient conditions.
Consistent manure injection system is important to maximize effectiveness of the injection process, and Zero-Max’s overhung load adapters (OHLAs) provide more-consistent operation in addition to the benefits for seals, shafts, and bearings. They provide a stable mounting platform and bearing support between the hydraulic motor and the blending impeller used on the machine’s distribution manifold.
Zero-Max offers OHLAs in more than 1,300 designs to meet a wide variety of load system requirements. These designs include custom inverted bearings and multiple lubrication ports that increase the overhung load adaptor’s load capacity and bearing life, and provide smooth rotational motion.
Designed for either face or foot mounting, standard OHLAs are available with SAE mounts, include A, B, C, D, E, and F mounts with 2- or 4-bolt flanges. They also come in a variety of variations, including splined, threaded, tapered, and extended output shafts. OHLA shafts are machined from 130,000 psi stress-relieved steel.
For more information on overhung load adaptors, call Zero-Max, Inc. at (800) 533-1731, or visit its website.
