tank and regulator not compatible

By KJArtWelder Date 12-29-2005 20:10

Hi,
I am an art welder who has just bought a oxy-acetelene set up. I also bought a tank from my local welding supply. the problem is my regulator (weldmark brand) has a male valve and left handed threads, while my tank has a male valve and right handed threads. I am a little confused as what to do next. Is their an adaptor I can buy? Or should I get a new regulator. The tank I have is one I will be swapping out, so will all tanks have the same type of threads and valves? Or do they differ. Thak you so much for the help,
KJ

By supermechanic (**)

Date 12-29-2005 21:36

Sounds like you have a Presto-Lite ("B") tank.
Adapter is needed, weld supply house that sold you your outfit should have provided you with adapter nut.
This is a common item, though a small store might not have one in stock.
Call and make shure they have one before you waste a trip.

By TimGary (****)

Date 12-29-2005 22:39

Tanks and regulators for Oxygen have right handed threads.
Tanks and regulators for Fuel Gas have left handed threads.
This is done on purpose so that you don't mix them up.
This is also done to remind you of a couple of safety concerns:
1. Never use regulators, fittings or hoses that have been oiled for oxygen as when pure oxy meets oil in a closed - pressurized condition, it spontaneously ignites and or explodes.
2. Never use acetalyne at pressures over 15 PSI as this may cause it to spontaneously explode.

Tim

By supermechanic (**)

Date 12-31-2005 14:49

TimGary;
Please tell me what threads are on a "b" acetylene(presto-lite) tank.

By TimGary (****)

Date 01-02-2006 13:28

Hi,
I'm not familiar with Presto-Lite products.
I would bet though that they follow the industry standard and put left handed threads on their fuel gas equipment.

Tim

By supermechanic (**)

Date 01-02-2006 20:37

Presto-Lite tanks are left-overs from the days of acetylene headlamps on automobiles.(Hence "presto" ,you didn't need to wait for the acetylene generator to make enough gas to light your headlamps, you just open the tank and you light your lamps).
Commonly known as plumbers tanks, or 'B' tanks.
They have a right handed thread, which is what KJArtWelder has found on his set-up, " my tank has a male valve and right handed threads".
These tanks have been in existance before there was a 'standard'.
I would guess that tens, if not hundreds of thousands of these tanks are in existance.