Greenheck Fan FA/103-00 Light duty bearings, Air handling quality, Ball bearings, Application

Ball Bearing with rubber sleeve

and stamped steel housing.

Greenheck Product Application Guide

locations on the shaft; thrust loads; and the direction of belt pull. Most often the selection program used is one developed by a bearing manufacturer. Greenheck engineers use Dodge bearing selection software. Based on the output results of this data, Greenheck engineers are able to select the bearings that best meet each individual application.

Light duty bearings

Ball bearings with stamped steel housings are well suited for applications with very light loads and lower speeds. The main design characteristic that defines stamped

bearings is the rubber sleeve around the bearing insert, which snaps into the stamped housing. The use of these bearings is limited to fan products with 3⁄4 inch and smaller diameter shafts, and one

horsepower and smaller motors.

Air handling quality

When the operating level of the ball bearings with stamped steel housing is exceeded, air handling quality ball, spherical or tapered roller pillow block or flange-mount bearings are primarily specified.

These bearings have been engineered specifically for air handling applications and feature special construction and tighter quality control. In order for a bearing to be of “air handling quality,” it must meet the following specifications:

1. Reduced swivel torque

Proper alignment of the bearing to the shaft is essential in preventing vibration, noise and damage to the bearing components. To allow a bearing to self align under light loading, it must have a low swivel torque. A low swivel torque enables the outer race of the bearing to pivot or swivel within the cast pillow block, allowing the bearing to align to the shaft much easier. It should be noted that this feature is special only to air handling ball bearings and tapered roller bearings. Spherical designs inherently allow for easy self-aligning because the race has a radius that allows the rollers to pivot

somewhat within the race, so the race doesn’t need to pivot within the pillow block.

2. Noise and vibration testing

All “air handling quality” bearings are 100% vibration tested. These high test standards are designed to discover microscopic manufacturing defects that may either cause higher noise levels or lead to premature failure of the bearing.

3. Bore Size Test

All “air handling quality” bearings are 100% inspected to insure that the inner race diameter is within tolerance. A bore size larger than tolerance would allow the bearing to shift which could cause misalignment.

The benefits of “air handling quality” bearings to the life of ventilation equipment are being seen throughout the HVAC industry. More and more manufacturers are providing air handling quality bearings as their standard.

Ball bearings

The Dodge D-Lok pillow block bearing incorporates a “heavy-clamp-style” locking collar as an alternative to the typical set screw locking system. This design allows the bearing race to be tightened concentrically about the shaft. This type of locking mechanism gives two distinct advantages over the set screw method. First it maintains one common center axis of the shaft and bearing, whereas tightening of the set screw forces the shaft off to one side, offsetting its rotating axis. Secondly, the shaft and bearing race come into surface-to- surface contact upon tightening. This increase in contact surface area not only improves the holding strength of the bearing to the shaft, but it also eliminates problems with burring on the shaft caused by the tightening of set screws.

Application

Greenheck uses Dodge D-Lok ball bearings for all centrifugal, vane axial and industrial units within the ball bearing application range. In our fan and ventilation line, Dodge D-Lok ball bearings are

Ball bearing with D-Lok

Fan Application No. FA/103-00 ® 3