> I don't know how it is with acetylene but with propane you need
> a two stage regulator since it begins as a liquid and is changing
> into a gas. I had the same problem with my propane until I installed
> a two stage regulator.
The change from liquid to gas does not make it necessary that you use
a two stage regulator. The important thing it that you keep the tank
right side up on both propane and acetylene. If the tank it not right
side up the liquid will enter the regulator and cause problems.
Since propane is liquid in the tank, the pressure in the tank will
remain relatively stable, unless it gets cold. A propane tank is only
pressurized by the liquid turning to gas. This pressure is only about
100 psi. This effectively does the same thing as the first stage of a
two stage regulator.
Acetylene is a gas that has been absorbed in acetone and a filler
material. I has stored at a higher pressure. Think of it like Coke or
7UP. If you take off the lid it fizzes all over. Granted the pressure
is much higher. But the same thing happens inside the tank when you
open the valve. If you let the gas out too fast, the acetone will come
out with it. The tank size must be large enough to supply the amount
of gas that the torch needs without this happening.
Here is difference between a two stage regulator and a single stage. A
two stage regulator drops the pressure from the tank to a preset
pressure that is above your the intended pressure. For the sake of
argument lets say tank pressure is 2000, the preset first stage drops
it to 120 psi and adjustable second stage drops it to 3-15 psi
A single stage drops it from tank pressure to working pressure in one
The main reason to have a two stage regulator is to solve the
problems that arise when you have a fluctuating tank pressure.
Fluctuating tank pressures can be caused by using multiple torches at
the same time or high consumption.
I hope that I have helped.
Timothy A. Hansen
TAH Handcrafted Jewelry