N/A Pressure Cooker

[Terry]

Hi all,

My wife's pressure cooker is missing the weight that sits on top of an 1/8" barb of her pressure cooker. When operating normally, the weight bounces up and down and lets the pressure cooker maintain 15 pounds of gauge pressure.

It is a 21 quart cooker. 11" high, without lid, and 12 1/2" diameter.

I am ordering her a new pressure cooker.

Question: How would you determine how heavy the weight should be to maintain 15 pounds of pressure?

The weight, as I remember it, would feel about 1 pound. Anyway, does anyone know how to figure the weight? (Wife doesn't think the weight/pressure regulator weighed over 6 or 8 ounces.)

Thanks,
Terry

 

[Capt. Geoffrey Thorpe]

Weight of the thingie divided by (diameter of the steam hole squared * pi /4) = 15

so


Weight = (15*4)/(diameter squared *pi)
That was wrong

Where 15 = pounds per square inch, the diameter is in inches, and the weight is in pounds

 

[Terry]

So.........

X = 1/8 * 1/8 = 1/64(3.14/4) = 0.012265

The steam hole is 1/8" in diameter.

Do I then multiply the answer by 16 to convert ounces to pounds or is the weight 0.012265?

Terry

 

[Capt. Geoffrey Thorpe]

So.........

X = 1/8 * 1/8 = 1/64(3.14/4) = 0.012265

The steam hole is 1/8" in diameter.

Do I then multiply the answer by 16 to convert ounces to pounds or is the weight 0.012265?

Terry

You forgot the 15 - and I goofed moving things to the other side of the equation - forgot the diameter squared * pi was in the denominator in the first one.

So it's

W = 1/8 *1/8 *pi *15 / 4 = .18 pounds or 3 ounces


If the bottom of the hole in the weight thing is concave so that it touches the steam vent around the outside, you want to use the outside diameter of the vent in the calculation.

 

[Terry]

Geoff,


You the Man!

Thanks,

Terry

 

[PaulMillner]

the weight bounces up and down

Thanks,
Terry

A buddy whose a cook says you're doing it wrong. If the weight is bouncing, reduce the heat. You're needlessly venting moisture that's better left in the food, and with some recipes, notably tomato purees, risking messy vent plugging, which causes the safety to blow, coating the kitchen with schmutz.

Instead, the weight should just simmer slightly. Try it! The idea is to cook with pressure without toughening the meat with excess heat.

Paul