Pressure and bucket design

[kotis]

buket disign

Hello People,

A friend in High school recently came to me with a problem regarding pressure.
He was wondering whey it is that bucket manufactures prefer the shape of the bucket resembling a frustum rather than a basic cylindrical shape...

Any ideas?

Regards,

Luke.

 

[stefannm]

I noticed that no one has replied. I am curious to get other input on this as well.

I think in most cases, pressure differences are not a major concern for normal sized buckets. The biggest reason for the angle on the side walls would be related to manufacturability. In most cases, forming the bucket will require a mold of some sort. In the end you have to remove a fully formed bucket from the mold. Adding an angle to the walls reduces the friction during the removal of the bucket. In plastics, this is referred to as draft.

 

[kotis]

That was an angle which I had no idea about... but it suffices... except not for this particular case... he is insisting it must be pressure related because their teacher gave them the question after the covering that topic... liquid inside the bucket and the atmosphere...could the surface area of the bucket have something to do with the bucket design?

 

[kotis]

Hello again,

For anyone interested in this: I have been asking around and some friends were suggesting that the small surface area at the bottom of the bucket would lead to a smaller force acting on the bottom for equal depths of contained liquid.

The other was that by design, it is usually easier to carry the bucket designed as a frustum than when the shape is a pure cylinder.

 

[jorgito]

Hello kotis,

Although what you said is correct, I would forget all about forces, pressures and material resistance related to bucket design.
Buckets have the shape they have because it is easier to pile up, requering less space.
Plastic buckets, as said, have the aditional constrain of easy molding.
Regards!