Schaeffler bearing mounting cuts costs on Spanish cement roller press

First published in the October 2013 issue of Quarry Management as Mounting Matters

Correct bearing mounting cuts costs on cement roller press

The correct mounting and dismounting of rolling-element bearings can save time and dramatically increase the life of the bearings, as well as maximize the availability of critical plant and machinery by avoiding costly breakdowns.

The key is to ensure that the appropriate tools and equipment for the mounting and dismounting of the bearings are on hand for the engineer at the installation or assembly stage. Appropriate tools may include thermal mounting and dismounting tools (ie heating plates), induction-heating devices, mounting paste and heating rings, as well as feeler gauges, hydraulic extractors, hydraulic nuts and hand-pump sets. Using the correct tools ensures that bearings are mounted and removed easily and quickly, without causing damage to the bearings or surrounding equipment, and in a safe and reliable manner.

Portland Valderrivas, Spain

Grupo Cementos Portland Valderrivas is the largest group of cement manufacturers in Spain and one of the world leaders in the industry. In 12 out of 17 regions in Spain, product diversification is helping the Group to obtain a large share of the Spanish cement market. The annual production capacity of the El Alto cement plant, for example, is approximately 2.25 million tonnes of grey clinker; 230,000 tonnes of white clinker; 2.8 million tonnes of grey cement; and 280,000 tonnes of white cement. There are two production lines at the plant for grey cement and one line for white cement.

When four bearings in the roller press at El Alto had to be replaced, having reached the end of their maximum service lives, Portland Valderrivas contracted Schaeffler to carry out the mounting of new bearings and to show fitters from the cement company’s engineering service provider exactly how to do this. The four new bearings provided by Schaeffler were spherical roller bearings with tapered bores. The bearings each weighed 1,650kg and measured 630mm x 1,090mm x 336mm.

Due to the large size of the bearings and the importance of the press to the production process, correct bearing mounting was of vital importance, not only to the quality of the finished product, but also to plant availability. Schaeffler supported Portland Valderrivas’s engineering service provider in planning and co-ordinating the mounting operation, and during the mounting procedure service experts from Schaeffler conducted on-site training for the fitters. The four new bearings were mounted using a hydraulic mounting tool, while adjacent components and bearing seats were handled with care and checked to see if they could be reused.

Customer benefits

Correct bearing mounting is essential to ensure a high level of machine availability and to maximize bearing service life. Due to the joint efforts of Schaeffler and the engineering service provider, the risk of a bearing failure, which would have resulted in two days’ unplanned downtime, was reduced significantly. Furthermore, the transfer of knowledge from Schaeffler to the fitters ensured that the engineering service would have the capability to correctly carry out similar bearing mounting tasks without assistance in the future.

Potential savings

The cost of providing a professional-standard bearing mounting service was as follows:

• Labour (10 fitters for five days): €6,000
• Crane hire: €5,000
• Four spherical roller bearings with tapered bores: €114,000
• Mounting assistance: €3,000
• Total cost: €138,000

This compares with a potential production loss due to unplanned downtime (48 hours) of c.€240,000.

Online bearing mounting guide

To help companies correctly mount and dismount rolling bearings, Schaeffler have launched an interactive online information guide. The Schaeffler Mounting Toolbox is a web-based guide on how to professionally install rolling bearings and the tools required to do this. As well as learning about which tools and fitting aids are required, users can also view short educational videos that demonstrate how these tools should be used in practice.

On entering the website, users are presented with a ‘Virtual Plant’ home screen, which serves as the main user interface, allowing fast, easy navigation around the website and easy access to the information provided. The objective is to make users feel that they are actually in a factory, looking over the shoulder of a professionally qualified Schaeffler bearing mounting service technician who is demonstrating how to correctly mount the bearings.

The website provides details of mounting tools and accessories, and demonstrates the benefits of correctly mounted rolling bearings, which include longer operating life for the bearing, reduced unplanned downtime, and higher machine availability. Moreover, correct alignment and lubrication can help achieve improved energy efficiency of machines and equipment.

For further information visit: www.schaeffler.com

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