Meaning of the term "Boot"

[mechatronic]

Hi ,

Please let me know the meaning of the term "Liquid Boot required" . , how to calculate and significance of this term

 

[MortenA]

A boot is a "piece of pipe" in the bottom of a three phase separator usually upstream the weir.

The heavy phase (water) will collect here and give your process control a lower holdup time (for the part in the boot).

Usually a company standard will include how to size it. E.g. Shells DEP 21.22.05.12 specifies that the minmum length of the boot is 1 m. The actual length is defined by control needs also specified in the company standard.

Best regards

Morten

 

[mechatronic]

Thanks a lot MortenA . I am working on vertical sump pump of API 610 , VS1 type .

I will check Shell DEP too , thnnks a lot

Regards,

mechatronic !

 

[katmar]

The term boot can have many meanings (apart from footwear!) and while I agree that what Morten has described would be called a boot, I do not think this is what you are after. Any piece of pipe designed to allow a bit of residence time is often called a boot. Even the drip leg down to a steam trap can be termed a boot.

But I think that what you are after is what I would term a "shroud". At the inlet to the suction of a sump pump it is sometimes done that a reducer or specially shaped cowl is installed to allow gradual acceleration of the fluid.

I would also not be surprised to hear a deepened section of a sump (where the suction pipe would be) called a boot.

So there are many things that could be called a boot and if I were in your shoes (or boots!) I would go back to whoever specified "Liquid Boot Required" and ask for specifications of the boot.

Katmar Software
Engineering & Risk Analysis Software

http://katmarsoftware.com

 

[mechatronic]

Katmar,

Thanks for the efforts in bringing clarity to Mortens' reply.

I will give little more inputs. See if any of you can bring more clarity .

Supplier says the boot is

(total pump's length + Distance betn bottom of the sump to underside of the pump)- ( Sump height + manhole standout or height of the nozzle provided at the top of the sump)

By this formula I am no way able to understand what this term " boot " physically mean !!

It could be a shroud or pipe , but what role it plays in functioning of a pump ?

As regards to cavitation / NPSH the supplier has given the data on minimum submergence.

Regards,

mechatronic

 

[katmar]

Your supplier's description is very confusing and does not really help me.

After sending my previous post I remembered that I have seen sump pumps where there is a small reservoir installed in the suction piping to ensure self-priming. Perhaps this is what they are after? Ask them for a drawing.

Katmar Software
Engineering & Risk Analysis Software

http://katmarsoftware.com

 

[JJPellin]

Based on your description, it sounds like they want a well at the bottom of the pit with the suction of the pump in the well. This is common with tanks if you want the pump to be able to pump the tank completely empty. Many of our tanks have a large flat bottom, but at one end is a small section that is a pit that drops down below the rest of the tank bottom. The suction to a pump comes off from the bottom of that pit. This allows the pump to pump the tank almost completely empty. It sounds like they are asking you to do the same thing in your sump. If you put the suction of the vertical pump in this "boot" you can come closer to pumping the pit dry.

 

[25362]

Another definition (petro eng) for boot is "surge column". Meaning a large-sized pipe of sufficient head able to absorb liquid surges.