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3

# Double Pass Sieve Tray

3 replies to this topic
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### #1 xSammie

xSammie

Brand New Member

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Posted 01 June 2023 - 10:02 PM

Hi all, I am currently designing a double pass sieve tray. Would like to check if I have to divide the weir length by half or multiply it by two when performing the calculation as per a cross tray design heuristic? From what I understand, we can determine the weir length of a cross tray design by multiplying a factor of 0.77 to the column area. In this case of a double pass, what should be the right approach?

### #2 breizh

breizh

Gold Member

• 6,075 posts

Posted 01 June 2023 - 10:14 PM

Hi,

Check it out:

https://www.cheresou...ss-sieve-plate/

Breizh

### #3 xSammie

xSammie

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Posted 01 June 2023 - 10:34 PM

Hey Breizh, thank you for the prompt reply and help!

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Posted 09 June 2023 - 03:49 AM

Hi all, I am currently designing a double pass sieve tray. Would like to check if I have to divide the weir length by half or multiply it by two when performing the calculation as per a cross tray design heuristic? From what I understand, we can determine the weir length of a cross tray design by multiplying a factor of 0.77 to the column area. In this case of a double pass, what should be the right approach?

Hi,

these are simple geometry calculations, e.g. you have a diameter of the column, to estimate the weir length, the other parameter required is downcomer width (for both, side and central in case of two pass tray). The weir length is chord length which you can estimate based on the simple geometry formulas.

The two pass tray will have either two side downcomers or one central downcomer (odd and even trays). The weir length will help you to estimate the weir load (refer acceptable limits so to adjust the downcomer width).

One key point - ensure to keep the weir length of odd & even trays same to ensure all trays will hit the limit simultaneously.

You can refer my post (others have shared the link in their responses) for detailed hydraulic design.