Air Lock In Floating Suction

[pentatech]

We have supplied Single Arm 24"NB Floating Suction Assembly with Swing Joint for Jet-A1 Above Ground Tanks. It is observed occasionally there is Air Lock in the system and not at any specific level in the tank or suction flow. Can anyone suggest reasons for the same. Operates feels that Suction Mouth comes out of the liquid and air enters the system but we are not able to understand the reason for the same.
Please suggest.

 

[LittleInch]

Vortex maybe?

Leak somewhere.

Give us a drawing or a sketch to have any idea.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[Artisi]

Or photo of installation.

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

 

[Artisi]

How are tanks filled, ie. discharge into the tanks?

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

 

[pentatech]

Thank you for your prompt replys.

Vortex Breaker is provided at the suction end.

No Leakage is checked in the system.

Our GA drawing Layout is attached for reference.

Please check and suggest.

Thanks in advance

 

[LittleInch]

Well even with a anti vortex plate, at high angles the inelt pipe is closer tot he surface than at lower angle and also nearly horizontal.

Hence air could much more easily enter.

What flowrate / velocity is this?

Do you use the same pipe for filling and discharge?

If the swivel joints get stiff then again at higher angles there is less force pulling the pipe down.

What is that strange line on the section - there to hold the pipe up during maintenece?

Is that a cable exiting nozzle N5?? What is it doing? Can it get jammed and hold the pipe up? what force is on that cable?

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[HTURKAK]

Apparently , min. top of pipe level = 1140 and LLLL =1150. The low pump-out level should be at least 150 mm above the top surfaces of deflectors or suction line vortex breakers to avoid air entrance.The statement 'occasionally there is Air Lock in the system ' implies the attempt to pump out the unavailable inventory .