Virtually all high-tech and legacy machines have something fundamental in common: bearings. The choices and characteristics of industrial bearings and complementary solutions are continually advancing. New options improve bearing and machine life, increase efficiency, decrease downtime, and simplify how the components are installed and maintained.
The most common causes of bearing failure are contamination and improper installation. “These two modes represent about 30% of why bearings fail,” says Kris Leming, product manager at NTN Bearing Corp. NTN SPAW mounted units, designed to mitigate both concerns, are direct replacements for SAF-style bearings that have a high rate of premature failure.
The contact area of NTN SPAW’s spring-loaded heavy contact seal is on the inner ring of the bearing insert rather than the shaft, which helps block the intrusion of contaminants such as liquid and fine particulates. Because the one-piece solid bearing unit is “shaft-ready” out of the box, it installs up to 60% faster than a standard SAF unit, says Leming.
Split cylindrical roller bearing housed units from Timken let customers reduce fitting time by as much as 90%, says Nick Dent, business unit manager at The Timken Co. “These units are completely split to the shaft, meaning you don’t have to remove couplings, gearboxes, or other equipment to install the bearings,” he adds.
The Timken unit reduces downtime and maintenance costs in trapped and other hard-to-access applications because its removable support caps and housing halves simplify inspection and replacement. It is interchangeable with conventional as well as split units.
NSK’s new high-efficiency bearings are designed for high-efficiency motor applications. The company’s approach to reducing the 1% of mechanical losses that bearings account for in an electric motor’s overall efficiency is focused on bearing lubrication, says Tim Jasina, senior application engineer at NSK.
Providing the optimal amount of a special grease developed by NSK minimizes churning and the resultant power loss. To achieve extended elastohydrodynamic lubrication (EHL), the thickener and synthetic base oil’s properties assure proper oil film development and excellent durability across a wide temperature range, Jasina explains.
Traditional bearing isolators allow contaminants to enter the bearing housing when the equipment is shut down as the housing attempts to reach equilibrium. The EXP bearing isolator from Sealing Equipment Products Co. (SEPCO) is designed to take immediate control of the bearing housing by blocking the breather and directing the air through the noncontact seal.
“As the airborne contaminants/vapor enter through the seal’s axial throttling gap, the seal begins to break down the contaminant’s energy and it continues through the long radial gap where the energy…is broken down further and converted to condensate,” says Woody Nepa, engineer for product development and reliability solutions at SEPCO.Contaminants captured within the internal condensate trap can drain out through a small static weep hole, ensuring lubrication reliability.
New VB45-series bearing isolators from Inpro/Seal deliver IP66-rated contamination protection with a patented XX Interface that blocks contaminants from entering the bearing housing. To ensure permanent protection, the stator and rotor form a noncontacting compound labyrinth seal with no wearing parts.
The patented bearing isolators “offer a compact design and performance measures that exceed previous generations,” says Neil Hoehle, chief engineer at Inpro/Seal, who adds that offered variants are universally suited to any lubrication or other operational condition, regardless of the application.
Modern condition management
Remote access to online data from bearing condition monitoring sensors enables well-timed, effective maintenance decisions. The new, wireless ABB Ability smart sensor for Dodge mounted bearings monitors vibration and temperature – two parameters that provide early indication of potential bearing failure.
“Not only does this give early notice to problems that need attention, but it also allows the customer to notice trends across applications,” says Vasilios Kapousidis, development engineer for ABB’s motors and generators business.
Fluke 3561 FC vibration sensors are motor vibration sensors that detect early issues from common mechanical faults such as imbalance, misalignment, looseness, or bearing wear. The triaxial sensors deliver continuous condition measurements while the asset is in use. When issues are detected, users receive remote, automated alarm notifications, allowing them to make better decisions on when to make repairs.
This ability to screen machine health and proactively address signs of wear reduces the costs of labor, repair, parts, and energy, says John Bernet, application specialist for mechanical reliability at Fluke.