Re: Thermal Expansion Of Bucket Elevator
As things stand, Ho Ho, with the elevator there are a few unknowns. "What can you afford to distort?" is a good basis for examination. If you can mount the connecting bits, whatever they might be, on the usual slot & shoulder bolt set up you will be home & dry. Saves messing about with the machine proper.
I'm reminded of the self appointed Piping Designer who designed a high pressure steam line in a large petrochemical refinery in the North of England. On start up the pipe bents swayed about a bit & some rather important joints in product lines sprung leaks. The alleged designer's reply was " Nobody said nowt (anything) to me about expansion!" It was a long time ago; but even so it makes you wonder. ■
John Gateleyjohngateley@hotmail.comwww.the-credible-bulk.com
Re: Thermal Expansion Of Bucket Elevator
I am thinking of vertical movement from day to day. The elevator is connected to the floor (obviously) and to a square-section rigid duct at the top. My concern is distortion of this duct due to the elevator moving. Does anybody else see this as a concern? ■
Re: Thermal Expansion Of Bucket Elevator
So, taking a 'scientific' engineering approach
1) establish the true material temperature at the elevator inlet
2) establish the true material temperature at the elevator outlet
3) establish the specific heat of the material
4) calculate the heat lost by the material while in the elevator
5) make an estimate of how much of the heat loss is passed (by radiation?) to the elevator casing
6) calculate the temperature rise of the casing allowing for radiation from the outside of the casing
7) calculate the linear expansion on the casing due to the temperature rise
8) make a decision if an expansion joint is required
Alternatively, do what I would do. Find an elevator handling hot material and try putting your hand on the casing to see if it's actually hot or just mildly warm. If warm don't worry. ■
Re: Thermal Expansion Of Bucket Elevator
You should look at it.
Thermal expansion can create a lot of force
This will go somewhere - we have experinced this in some ductings
We had a belt elevator with same arrangement but less temp and someone decided to fit a drive access platform tied to structure and elevator > on one side and led to mis tracking !!!
If if does not look right, then it is not.
Cheers
James ■
Re: Thermal Expansion Of Bucket Elevator
Thank you Designer and James
Thank you for your valued replies.
The 'scientific' approach looks very thorough and will give the correct answer. But of course it relies on a lot of measurements and assumptions that I could not lay my hands on.
My only personal experience is with 20m belt/bucket elevators carrying mineral sand at <200 degC, and they were too hot to touch.
Regards
Adrian ■
Thermal expansion of bucket elevator
G'day all
I am wondering if we may get problems with our 22m chain elevator which carries material of approx 300degC. The design of the outlet chute currently does not take in to account any vertical movement.
Elevator installations I have seen before, do allow for this, but what would be common practice?
Thanks
Adrian Brewster ■