Whites Relies On SKF Bearings For Bell Hanging

Bell-hanging company Whites of Appleton is continuing to use SKF bearings, as it has been since the 1920s. At full swing, a church bell can exert a force equivalent to four times its own static weight. For this reason, the way it is mounted is crucial - to contain these forces and to deal with the way these bells hang idle in one position for a long time before being oscillated through 380 degrees.

Whites of Appleton manufactures, supplies and installs most bell-related solutions, apart from the bell casting and tuning. It works all over the country and has many high-profile installations on its books, including St Paul's Cathedral, Windsor Castle and Canterbury Cathedral. According to Brian White, a partner in the company: 'The headstock design has changed significantly over the last century, with timber headstocks being replaced by those made from steel and cast iron, but the one thing that has not changed since the 1920s, from our perspective at least, is the use of SKF bearings.

'At the horizontal position of the swing, the bearings will experience a force equivalent to 2.5 times the static weight of the bell. 'At bottom dead-centre, this rises to four times the static weight, so once we know the weight of the bell, we know which bearing to go for,' he finished. Typically, depending on the application requirements, Whites opts for one of seven different variants in SKF's self-aligning ball bearings range, sourced through the Oxford Service Centre of Eriks.

The self-aligning ball bearings - supplied with tapered bores and adapter sleeves for easy mounting and dismounting - are particularly suited to applications that exhibit misalignment either in the shaft housing or bearing seat. They offer extremely low friction, low operating temperatures, reduced vibration levels, lower noise levels and, particularly advantageous for this type of application, low lubrication requirements.

Occasionally an installation may call for SKF Explorer spherical roller bearings made of patented SKF Xbite steel, which has a much longer life due to its increased hardness. Thanks to their ability to accommodate very heavy radial and axial loads in applications prone to misalignment, SKF Explorer spherical roller bearings can last several times longer than their rivals under typical heavy-duty conditions. The bearings are housed in SKF's standard SNL plummer block housings, which are available in a wide variety of sizes to match the bearing specified.

As well as offering a reinforced base, a variety of mounting options, good thermal performance and easy re-lubrication, their versatility means that it is seldom necessary to resort to tailored housings for specific applications. The bearing assembly is completed with Type C felt seals, which suit the semi-external environment and the shaft deflection. The whole assembly is lubricated using a general-purpose industrial bearing grease. Whites uses the bearings and housings to support the bell via two gudgeon pins that extend from either end of the headstock.

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NSK Ball Bearings Save Costs For Food Processor

NSK's cost-reduction programme has achieved annual cost savings on a potato processing line, as a result of replacing sealed, single-row radial ball bearings with NSK's Molded-Oil bearings. The bearing problem on the potato processing line centred on the rollers of a potato peeling machine. The harsh nature of the process meant that the sealed radial ball bearings in the rollers were subject to the ingress of water and dirt, causing them to fail consistently every six to eight weeks.

These frequent failures were resulting in extremely costly downtime. Added to this was the maintenance cost to replace the bearings; the cost of replacement bearings themselves and other expenses such as the re-greasing required at weekly intervals, as well as the holding of spares inventory. This added up to to a total annual loss of EUR189 (GBP168) for the potato processor. In the highly competitive world of food production this cost was not sustainable, so an initiative was launched with a view to sourcing higher-performance bearings.

As part of this initiative, engineers from NSK's cost-reduction programme were called in to give advice. The cost-reduction programme is a service designed to help bearing users to improve reliability, reduce operating costs and improve efficiency and profitability. These objectives are achieved by delivering tangible savings to assets, such as equipment and machinery, and also by improving the working knowledge of maintenance and engineering personnel. NSK engineers visited the food processor and identified the problem. They suggested using NSK's Molded-Oil bearings to prolong bearing life.

Molded-Oil bearings employ a special solid lubricant to transform the performance of machinery in environments exposed to high humidity, corrosion and contamination. The bearings achieve improvements in performance and reliability by offering more than twice the operating life of grease lubrication in water-contaminated environments. The solid lubricant technology also means that operating environments are kept free of grease and there is no need for refilling of lubricant, as Molded-Oil provides a continuous supply of lubricating oil.

Sample Molded-Oil bearing inserts were fitted to the rollers of the peeling machine and operated successfully for more than 10 months without problems. The bearings were then removed for inspection having already provided more than four-times the life of the previous single-row radial units. The inspection revealed that the bearings required no maintenance and so continued in operation. The food producer has now replaced all the single-row radial ball bearings on the potato peeler with Molded-Oil units. In addition to providing improved life, these bearings are also saving the customer the cost of re-greasing.

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