NTN Bearing SPAW/SPW Series Heavy Duty Cylindrical Roller Bearing Unit Application Case Introduction

A manufacturer of hardwood lumber and flooring products in Yichang, Hubei, China, had repeated premature bearing failures in its unloaders and drag chain conveyors. According to statistics, such repeated failures result in 72 hours of equipment downtime each year, resulting in a loss of production costs of approximately RMB 500,000.

In November 2018, the company contacted us and we responded quickly by immediately dispatching an engineer with rich experience in the field of heavy-duty conveying to Hubei to conduct a thorough diagnosis of the relevant equipment in the plant. It was found that the average life of the bearings was only one month due to frequent contact with bark, dirt, sand, sawdust and water. In addition, the experts found that the company used two sets of four pairs of ball bearings at both ends of the heavy-duty drag chain drive shaft, which could not meet the use requirements, so a large number of bearings needed to be stocked each year for rapid consumption.

After careful study, the engineer recommended that the bearings be replaced with NTN's SPAW heavy-duty roller bearing units, equipped with end covers for sealing. NTN's SPAW/SPW series heavy-duty mounting units use sealed spherical bearings to provide excellent protection in severely polluted environments. In addition, the end caps provide maximum bearing seal protection, preventing the accumulation of large amounts of heavy debris.

In addition, engineers determined that a single SPAW bearing at each end of the chain conveyor shaft was sufficient to carry the heavy load of the drag chain, thereby reducing bearing inventory requirements.

From 2019 to today, NTN SPAW has performed flawlessly! The SPAW heavy-duty roller bearing units with covers installed in 2019 continue to operate smoothly in harsh, wet and dirty conditions, and are estimated to save/earn the company $1 million in the first year, both inside and outside.

The first choice for heavy-duty and contaminated environments, sealed spherical flange bearing housing units. SPAW/SPW type:

1. Heavy-duty, one-piece, rugged ductile iron housing that can withstand the impact and shock of falling debris and cold operating conditions;
2. Spring-loaded, single-lip contact bearing seals provide excellent sealing protection against water and contaminants;
3. With additional optional end covers to protect normal use in severe debris and contamination environments* (2 open end covers, or 1 open end cover and 1 closed end cover);
4. Bearings, lock nuts and adapter sleeves are all phosphate coated for corrosion protection;
5. Pre-lubricated and factory sealed for fast installation and trouble-free start-up;
6. Versatile scenario use, repositionable snap ring for fixed or floating operation;
7. Plug-in replacement of split shell bearings allows faster and easier installation than SAF/SN units, with the same base to shaft center height and bolt position.