Production and manufacturing

Commercial production can produce products in different quantities and through different means. There are five terms used in relation to manufacturing a product:

or one-off production

Scales of production

Prototypes and one-off production

In one-off production, an individual item is designed and made to meet a client's specification. At this level both time and material costs are high, and a high level of design and manufacturing skills is required.

There are many ways to produce a - some are rough and look like models and others are well finished and function as intended. It is now possible to metal, and many engineering companies have welcomed this technology as 3D printing is classed as , rather than subtractive. Additive manufacture builds up the metal form in layers, whereas takes material away from a larger piece. There is very little waste when using additive techniques, making it more environmentally friendly.

Additive and subtractive manufacturing shown alongside each other. In additive, material is added to create a shape whereas in subtractive it is taken away from a larger piece, leaving waste.

A custom-made or product that is made from metal could be made based on a customer . Products such as rings and jewellery are often made personally for a customer and only one will ever exist.

Batch production

Batch production is where many items of the same product are produced, such as a bike frame or parts for a metal fence. Many metal products are joined by , often done by hand rather than by machines, and the metal is held in place with a during the manufacturing process. The jig ensures that each part stays in place whilst the welding is carried out.

When a product is made in a batch, it is often far cheaper per product than when making just one.

Example

A designer needs six 300 mm × 300 mm × 0.5 mm sheets of aluminium, which cost £5.00 each.

A 900 mm × 600 mm × 0.5 mm sheet costs £28.00. This information can be used to calculate which is better value for money.

Six 300 mm x 300 mm x 0.5mm aluminium sheets costing £5.00 each alongside one 600 mm x 900 mm x 0.5 mm aluminium sheet costing £28.00 for calculating material costs.

Cutting the larger sheet into six smaller sections would cost:

£28.00 ÷ 6 = £4.67 per sheet

Therefore, £5.00 - £4.67 = 0.33

= 33p saving per sheet

As a percentage:

(4.67 ÷ 5) × 100 = 93.4

100 – 93.4 = 6.6% saving per sheet

Question

For sheets of steel:

500 mm × 500 mm × 0.7 mm costs £6.00

1,000 mm × 1,000 mm × 0.7 mm costs £17.00

Four 500 mm x 500 mm x 0.7mm aluminium sheets costing £6.00 each alongside one 1,000 mm x 1,000 mm x 0.7 mm aluminium sheet costing £17.00 for calculating material costs.

How much of a saving, in both pounds (£) and percentage (%), could you make by getting the larger sheet cut into four pieces that are 500 mm × 500 mm?

Mass production

Manufacturing in huge numbers is categorised as mass production. This level of production involves standardised production methods, and the extensive use of automation. Because of the high set-up costs, mass production systems tend to be inflexible. Mass-produced metal products include door handles, barbecues and cooking utensils.

Scales of manufacturing

Lean manufacturing

puts a focus on efficiency to add value for a customer, simplifying manufacturing processes and reducing waste. The philosophy originated in the Japanese car industry and has since been adopted by many organisations. There are seven areas to lean manufacturing known as ‘The seven wastes’:

over-production - producing more than is required
transportation - the unnecessary movement of items
over-processing - processing too soon or too much
inventory - holding more than is required
motion - the unnecessary movement of people
defects - errors and mistakes
waiting - for someone or for an event to happen

The seven wastes lean manufacturing addresses - over-production, transportation, over-processing, inventory, motion, defects and waiting.

Just-in-time (JIT)

is triggered by a customer order. The correct amounts of materials are ordered in to cover the order, and these arrive just as they are needed by production. This saves money on storage, reduces waste and ensures there is no money wasted producing stock that will remain unsold. There are disadvantages to the system in that, if any part of the product cannot be sourced, have to wait for their order to be produced.

Metals - OCRProduction and manufacturing