Series System Reliability Property 2 Examples

There is a special and highly valuable message in these Series System Reliability Property 2 examples.

It is to simplify, simplify, simplify all your series system arrangements—both in production plants, and workplace jobs.


Slide 34 – Two Series System Reliability Property 2 Examples — Always Simplify, Simplify, Simplify Series Systems!


The above Series System Reliability Property 2 examples show the importance and business value of simplifying series systems.

Series System Reliability Property 2 for Parts in Series

The upper series of images relate to head pulleys used on conveyor belt systems. The left image is the pillow block bearing assembly arrangement used universally for conveyor head and tail pulleys. It has 14 parts, each of which can be incorrectly assembled. It is incredibly difficult to set-up bearings in a pillow block correctly and then properly mount the entire pillow block to the support structure.

Contrast the pillow block to the other option for mounting the head pully: bearings mounted in fixed frame housings. The fixed housing arrangement has only five parts, over half fewer than for a pillow block. Plus, the fixed frame is rigid and far more secure than the pillow block mountings.

There is no doubt that a head pulley mounted in a fixed frame configuration would be greatly more reliable than putting the same pulley in pillow blocks.

Series System Reliability Property 2 for Equipment in Series

The second of the Series System Reliability Property 2 examples compares a cooling tower design from the early and mid-20th Century, on the left, with a cooling tower design from the late 20th and early 21st century on the right. In the old design five components were needed to drive the fan—the electric motor, the motor-side shaft coupling, the extension shaft, the gearbox-side shaft coupling, and the gearbox. It is a difficult job to set the drive system up so that all components are mounted and aligned to a high standard and typically they are only positioned to the least quality that can be gotten away with.

In contrast the modern cooling tower drive has only the electric motor and a variable speed controller. The modern cooling tower drive design is vastly simpler and greatly more reliable as four of the five components use in the old installation are no longer present.

In both Series System Reliability Property 2 examples, the simplified design with fewer components automatically brings with it far better reliability, and consequentially far less maintenance costs and much fewer operational problems.


This slide is a companion to the new Industrial and Manufacturing Wellness book. The book has extensive information, all the necessary templates, and useful examples of how to design and build your own Plant Wellness Way enterprise asset life cycle management system-of-reliability. Get the book from its publisher, Industrial Press, and Amazon Books.

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