btec first engineering unit 1: the engineered world learning aim a know about engineering processes...
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BTEC First Engineering
Unit 1: The Engineered WorldUnit 1: The Engineered World
Learning aim AKnow about engineering
processes used to produce modern
engineered products
BTEC First Engineering
BTEC First Engineering
Unit 1: The Engineered WorldUnit 1: The Engineered World
Surface mount Surface-mount technology (SMT) is a
method for producing electronic circuits in which the components are mounted or placed directly onto the surface of printed circuit boards (PCBs). An electronic device so made is called a surface-mount device (SMD).
In the industry it has largely replaced the through-hole technology construction method of fitting components with wire leads into holes in the circuit board. Both technologies can be used on the same board for components not suited to surface mounting such as large transformers and heat-sinked power semiconductors.
BTEC First Engineering
Unit 1: The Engineered WorldUnit 1: The Engineered World
Printed circuit boardElectronic circuits in schools and
industry are normally manufactured through the use of PCBs (Printed Circuit Boards). The boards are made from glass reinforced plastic with copper tracks in the place of wires
Components are fixed in position by drilling holes through the board, locating the components and then soldering them in place. The copper tracks link the components together forming a circuit.
BTEC First Engineering
Unit 1: The Engineered WorldUnit 1: The Engineered World
Process of manufacturing a PCB and SMT
Printed circuit board (PCB) manufacture
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The Surface Mount Technology (SMT) process
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BTEC First Engineering
Unit 1: The Engineered WorldUnit 1: The Engineered World
Process of manufacturing a PCB and SMT
Printed circuit board (PCB) manufacture
Designing the layout
Producing the artwork
PCB etching
Drilling the board
Populating the board and soldering
The Surface Mount Technology (SMT) process
Apply solder paste to copper pads
Place components using pick and place robot
Conveyor belts are used to transport the boards to the
reflow soldering oven
The board is heated to a temperature that melts the
solder plate
Components are soldered to the surface of the board
The finished board is then inspected for imperfections
BTEC First Engineering
Unit 1: The Engineered WorldUnit 1: The Engineered World
© Pearson Education Ltd 2012. Copying permitted for purchasing institution only.
4 Scales of production
One-off Batch
Mass Continuous
BTEC First Engineering
BTEC First Engineering
Unit 1: The Engineered WorldUnit 1: The Engineered World
© Pearson Education Ltd 2012. Copying permitted for purchasing institution only.
One off
Batch
Mass
Continuous
BTEC First Engineering
Unit 1: The Engineered WorldUnit 1: The Engineered World
© Pearson Education Ltd 2012. Copying permitted for purchasing institution only.
Scales of production
One-off• Where just one product is
made for a customer.• Could be a prototype.
Batch• A set number of identical
products.• Some flexibility to
individualise designs.
Mass• Products produced in
large quantities.• Often involves
automation.
Continuous• Automated production
can continue for months.• Often produces low-cost
products.
BTEC First Engineering
BTEC First Engineering
Unit 1: The Engineered WorldUnit 1: The Engineered World
Characteristics of different scales of production
© Pearson Education Ltd 2012. Copying permitted for purchasing institution only.
ONE OFF BATCH MASS CONTINUOUS
Unit Cost High Medium Low Low
Tools & equipment
General Specialised Specialised and dedicated
Specialised and dedicated
Initial investments Low Medium High High
Production efficiency
Low Medium/high High Very high
Labour type SkilledSkilled/semi skilled
Semi-skilled/unskilled Unskilled
Labour costs High Medium Low Low