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Automation

Automating the hand processes

This relatively labour-intensive approach was used for almost a year before the success of their sales meant they were ready to invest more to reduce their labour costs in May 2000. Technical Moulded Systems spent some time trying different approaches.

First they tried a vibratory bowl sorter (link to TR Nut use of these) to line-up the pegs for assembly and attached this to a jig (G)with a pneumatically (G)operated lever to install the springs. The problems with this were twofold: the bowl sorters were not reliable enough in lining-up the pegs and the whole arrangement was too slow. So they would again need too many of these arrangements to keep up with the pace of the peg production.

For these reasons they turned to trying robotics, though aware that this would mean even higher capital costs. Calling in a specialist robotics firm for assistance, they developed a pick and place robot (G)to lift the newly moulded pegs in batches of 32 from the moulder on a metal plate. As pointed out above, the sprue and runners are broken clear of the mouldings as the tool opens so a small clamp was added to the robot behind the plate to hold them.

   The plate that holds the pegs while the springs are clipped in

The plate then moves over a scrap bin where the clamp releases the sprue and runners to be ground down and recycled into the moulding process.

   Finished pegs dropping from the spring inserter plate

Then it moves on and tips all 32 pegs - with no other clutter - onto a conveyor (G)belt which takes them away into a storage bin or silo.

   Pegs coming from the moulder dropping into the air conveyor system

The key to the design of this system was finding a way of ensuring absolute reliability in keeping the pegs in line as the springs were rotated into position.

Moving the pegs from the moulding machines

An air conveyor (G)is used to move finished pegs around. The first belt conveyor (G)tips batches of pegs into a hopper which feeds them at a steady rate into a pipe through which they are blown. These pipes are flexible so it is a simple matter to change from one hopper to another when necessary (Can you think of the two reasons why this becomes necessary? (Answer).

  Air conveyor feeds to storage silos

From the silos, the clothes pegs are taken, either as a flow of one colour, or mixed colours, to the final machine to complete the process ready for shipping the pegs to customers. This machine weighs out batches of pegs in the required numbers (20, 24 or 48) and drops them into a pre-printed polythene bag. It then welds the bag shut and transfers it to a box for shipping. It was installed to bring the labour costs to an absolute minimum as it meant that only one person was needed to oversee production, as all processes could be carried out by machines, and the pegs produced without being touched by human hands.

Mixed colours being fed from separate silos into the conveyor to the bagging machine

   The weigh and bag fill/seal machine

With production entirely automated and working reliably the company is now able to produce 33 million pegs per year from each moulding machine - that's 66 million in total, each year! All this and the back-up office takes place in a factory 20 metres square.

Boxes of pegs ready for transportation

Here is a summary of the approximate capital costs:

Injection moulding machines (each)	£70,000
Mould tool	£30,000
Moulder ancillaries (weigh, colour, mix)	£20,000
Handling robot	£30,000

The total investment to create the production facilities described above amounted to about £500,000.

  Task 3 - Capital investment or jobs for people?

Marketing

Selling enough of the product was obviously necessary to recover the amount of investment that had been made. However, getting so many orders that the company could not supply them in a reasonable time would have been almost as much of a problem. Keeping a manageable flow of demand is critical - and very difficult to ensure.

So it is very important that a new company investigates its potential market thoroughly, and as early as possible. From this, targets have to be set for the unit costs (G)of manufacturing and the selling price (G)of the product.

TMS seem to have been successful with this, setting the selling price initially at £1.99 for 20 pegs, and reducing this on large orders from major supermarkets and direct sales outlets to 99p for 24. If they made a mistake with anything it was in underestimating how long it would take to get the product on the market - it took between 18 months and 2 years. Selling to a large direct sales outlet was marvellous, but they took a year to get the pegs into their shopping catalogue and start to sell them.

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