“Your kitchen is better organised than this”

Meals are ready, clothes laundered and pressed, house cleaned – all regular and reliable. These activities require materials: ingredients, provisions, groceries, detergents...

Yet your house doesn’t look like a supermarket distribution centre. You’re not picking your way through Food Mountains in the dining room. No, the items are purchased with the intention of holding them for as little time as possible before being used. It is not only economic but, for many foodstuffs, essential because of their perishable nature. Yet with these tight restrictions it is still possible to produce varied meals throughout the week. This is made possible by forward planning. What meals on what days? What ingredients are needed? How fresh must the ingredients be? How much in advance can they be bought? Can I afford to buy them yet? Have I got the space to store them? All these details a good homemaker takes into account, and mostly intuitively.

These principles are also familiar to industrial and commercial operations. They are used in your manufacturing operation in the procurement and deployment cycle of your manufacturing operation. It’s even highly likely that very sophisticated computerised systems are used to model, optimise and manage the process.

Yet the strange thing is that rarely does this sophistication extend to how maintenance stores are run. Engineering maintenance departments place reliance on a belief that whatever part or material they need will be available; on demand and without notice. This philosophy  requires that someone somewhere, whether in their own organisation or somebody else’s, will have a store brim full of every item in every plant.

There are two crucial keys to successful engineering maintenance and neither is a large spares store. The best engineering maintenance store is no store...

The first key is equipment reliability by design, not accident. That is, design of the equipment and design of its maintenance programme.

The second is that all maintenance should be planned. Every effort should be made to eliminate unplanned maintenance.

Just as the maintenance event itself should be planned so should its parts and materials. If you know exactly what parts and materials you need, and you know when the job is to occur, there is no need to hold stocks of those items. Orders for the parts/materials can be placed so that they arrive in time, and only just, to be available for the work. This principle is well known as Just-in-Time or JIT.

A systematic process is required to achieve this principle. That process, very familiar in production planning operations, is called materials requirements planning or mrp. A tool from the MRP (Manufacturing Resource Planning) concept.

To illustrate how mrp works let’s consider a simple, single part need.

The part, let’s call it a widget, has a Lead Time of 8 weeks. Three are required for a job in 10 weeks time. The obvious arithmetic calculates that we need to order 3 in two weeks from now.