how the measure pressure?

i have a bag of certain gel and anther bag of silicon they are mall in size .
i want to know the pressure  of these tow bag  can you please help me 

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iceng6 months ago

Dear Lina,

My crystal ball is out for fixing.

Could you please add some pictures to to help us understand....

Are you wanting to test 2 => two, small different kind of bags ?

A] one made of gel ==> rubbery material

B] one made of silicon ==> crystalline material

Do you want to learn the burst (pop apart) pressure at ocean sea level altitude ?

Also look on the right ==================>>>>>>>>>>>>>>>>>>>>

You may see interesting instructables

lina mohammed (author)  iceng6 months ago

I have to make these bags with a specific pressure in eacih bag ...I guss this picture looks like what I am going to do


If you know the pressure needed the easiest method is to seal the bag in a pressure chamber with that desired pressure.. Pressure chambers can be found where saturation under water divers are decompressed...

Otherwise the bag will need to incorporate a medical needle permeable self sealing membrane and the injector would be a simple regulated air pressure piston. Once the needle is removed your bag will under the same pressure or burst... And as Steve said a low cost pressure gauge which can be found on a bicycle pump or a manometer which can be made with plastic tubing, water and red food dye are available to help you measure...

There certainly are manufacturers who can or already do make bags for medical applications... eBay may be a source of what you need...

lina mohammed (author)  iceng6 months ago

For pressure champer it's expensive to buy it ,I want to buy each used instrument ,, put i will try to findout some laboratories that enable me to use pressure champer.

Actually I looked everywhere for some thing like what I want but unfortunately what I need is some thing too small 4*4cm

To easily measure pressure in a bag...

Place the bag inside a used empty Coke liter plastic bottle. Tighten a modified cap (accepts a low pressure tube) on the bottle with a bag inside. Begin to pump air into the bottle with a used bicycle air pump with attached used pressure gauge.

When the bag inside the bottle begins to collapse (get soft) the pressure on the bottle is the pressure in the bag..

Does process this make sense to you ?

seandogue iceng6 months ago

+1. Very clever ice! Kudos for a scinetific mind.

lina mohammed (author)  iceng6 months ago

Thank you for helping me,,, yes it make sense to me and i will try do this process today ?

Don't buy, build. What pressure do you WANT in the bag ?

Use a pressure gauge or a manometer (depending on the pressure)

lina mohammed (author)  steveastrouk6 months ago

Could you please explain more how can use gage pressure , I think pressure gauge used for air bags pressure measurment ,I can't imagine how can I use it for measuring small bag pressure,

Thank you