Design for Disassembly and Assembly
2.3.1 Detailed description
URL:
Three main features of this product:
1. Easy to carry
​
Since delivery drivers need to carry this box, there are two handles added on the left and right sides. Also, to make this box light, the material is ABS, which is also recyclable.
​
​
​
​
​
​
​
​
2. Separable to two halves
​
In order to avoid contact with food, this box can be separated from the middle. To pick up food, users can just hold these two halves of the box and merge them from the left and right side of the food; thereby, the food is enclosed by the box and no contact with food is occurred at all.
​
​
​
​
​
​
​
​
​
3. Match pole magnetic tapes & drafted edge at the bottom
​
To keep the box closed, match pole magnetic tapes are attached at the three sides of the cross section. “Side A” magnetic tape is attached to the left half while “Side B” is attached to the right half that allows them to be attracted face-to-face. As the two halves of the box get closer, these magnets allow the box to be completely closed and able to maintain this position as well. The bottom edge of that cross section is drafted because this feature allows the food to easily “slide” into the box.
Cost Estimation:
The cost is estimated as $50. The plastic box (ABS) is assumed to be the same price of the Amazon product. Handles and screws are products from McMaster-Carr. The magnetic tape is also assumed to be the Amazon product in the URL above.
2.3.1 Bill of Materials
This Bill of Materials contain in total 6 different parts. Two plastic boxes and two handles are all made of ABS. They are also manufactured by the same process, injection molding. Two plastic boxes can be repurposed and reused because they can be some containers as well. The handles, however, can be reused as regular handles but it's hard to repurpose them. All these ABS components can be recycled because ABS is a recyclable thermoplastic.
​
The magnetic tape is made of both magnet and PSA. It is manufactured by rolling. Since this tape is consumable, it's neither repurposed nor reused. Unfortunately, magnet is not recyclable.
​
The 1/4'' screw is made of Black-Oxide Alloy Steel. It is manufactured by threading. It can be reused and recycled but not repurposed because it can only be a type of fastening component.
2.3.3 Disassembly process
The only two components of the product I want to repurpose are the two plastic boxes. To disassemble them, the tools I need are a screwdriver and a knife. First, use the screwdriver to release the screws from handles. Second, use the knife to carefully scrape off the magnetic tapes attached on the box surface. Then, the plastic boxes have been completely disassembled.
2.3.4 Design for Assembly
(a) The number of parts in the assembly is 6 based on the BOM table.
(b) The table below shows the Contact-free Delivery Box DFA Worksheet
The “Theoretical Minimum Number of Parts” is 3, because the sum of all the No’s is 3. It is possible to combine those two handles with two plastic boxes, although the injection molding process would be complicated because extra handles are required in the mold. If handles are successfully eliminated, there is no need to keep screws which are supposed to connect the handles and boxes. Finally, the last three parts - two plastic boxes and magnetic tape - cannot be eliminated because of the design purpose.