Vapor-compression refrigerators are manufactured through a process of cutting, bending, painting, and assembling metal sheets to form the internal and external parts. Components like the evaporator, condenser, expansion valve, and thermostat are attached to complete the refrigeration cycle. Refrigerators typically last 10-16 years before recycling, which involves removing coolant and separating materials. Ergonomic designs place frequently accessed parts at waist level for ease of use.

1. Vapor-compression cyclic
refrigerators
By / Aly Dawod

2. Introduction
• In this case study we will discuss the design and
manufacture processes of refrigerators ,
specially
Vapor-compression cyclic refrigerators

3. Introduction
• We all know about the essential use of refrigerators to
the consumer as well to the commerce.
• Consumer use it at homes to preserve their food fresh.
• Its commerce use is represented in keep the harvest
fresh till it arrives to the factory or to the market

4. Introduction
• Our example for this case study is the ordinary
refrigerator that you can find it at most of our homes.
• Knowing that its system ( Vapor-compression cycle ) can
be applied on bigger scales and for other uses as
mentioned.

5. The manufacture process
• The first stage of manufacturing is cutting and forming
the sheets.
• Cutting the sheets must be according to the specified
dimensions for the outer body of the refrigerator.
• The top and the doors of the refrigerators must be
smaller than the sides and the rear.

6. The manufacture process
• The next process is to bend and drill the sheets and
connecting the sheets together by Hemming then
washing the sheets and painting it.
Rolling
Bending

7. The manufacture process
• Then it pass Through a Desalination unit to get rid of
salts and fixing the painting.
• Then the drying process.
Painting

8. The manufacture process
• Painting is done by electrostatic method at 70 KV.

9. The manufacture process
• The second stage is manufacturing of the internal part of
the refrigerator.
• It is made using die press operation.
• 5m.m Plastic sheet.
• The process is accompanied with heat energy that help
the forming to take place faster.

10. The manufacture process
• Next Stage is assembling the sheets with the internal
body and fix them by hemming.
• Then we rivet them.
Riveting
process

11. The manufacture process
• The next stage is to manufacturing the freezer
• It is made by an aluminum sheet Which is bent on
machine which bend the sheet as a four faces cube.
• Then the back is assembled by a compressor.
• Then a frame is assembled and riveted.

12. The manufacture process
• The next stage is to attach the evaporators, one for the
upper part and one for the lower part of the refrigerator.
• The we adhere the evaporator to the body firmly by PVC
adhesive material to not release heat.
Evaporator

13. The manufacture process
• The next stage is to avoid condensation by attaching
condenser which convert the gas to liquid.

14. The manufacture process
• After that we attach the Thermal expansion valve
(throttle valve) which is control the amount of refrigerant
(Freon)

15. The manufacture process
• The rear of the Cabinet (the bottom) is as shown :-

16. The manufacture process
• The last stage is to attach a thermostat which must be
very attached to the body to sense the heat.
• Its function is to break down the circuit if the temperature
increase.
• And to turn it on if the temperature decreases.
thermostats

17. Ergonomics
• The top freezer refrigerator was never an ergonomic
success.
• It puts the most used part of the refrigerator down by the
floor where a lot of stooping and bending is required to
use it.
• Bottom freezer units are better, The main part of the
refrigerator is placed between waist and shoulder.
(French door refrigerator)

18. Ergonomics
• But the cost of top freezer refrigerators is less than the
bottom freezer ones.
French door
refrigerators

19. Product life cycle
• According to appliance Magazine's report in 2011 the
Average Life Span of refrigerators is between 10 and 16
years.
• The Virtual Repairman website's calculations are
between 8 and 14 years.

20. Product life cycle
• There are three main stages for recycling refrigerators :-
1) Chemical recycling by getting the coolant out of
the system.
2) Saw into three pieces to separate the metal,
foam, and plastic lining.
3) Metal, glass, and plastic recycling.

21. Testing and rating
• All the parts must be tested before assembling it. (the
compressor, the condenser fan, the thermostat …etc.)
• The cooling system and the refrigerant also must be
tested.
• The system must prevent over frosting.
Frost

22. Testing and rating
• The rating of refrigerators is based on many points like :-
- Capacity
- Storage and features.
- Water and ice Dispenser.
- Warranty and energy usage.
- Help and support.