Regulator Accessories FAQs
Straight answers to the questions people ask most about flowmeters, cylinder connectors, adaptors and other regulator accessories.
Why is the flow at my torch different from the flow on the flowmeter?
The flowmeter only tells you what is leaving the regulator, not what arrives at the nozzle. Leaks in the hose or fittings, a blocked or partly blocked nozzle, a long or kinked hose, and a damaged gas diffuser can all make the real flow at the torch different from the setting.
A draught can also blow the gas away from the weld even when the flow is right. If welds show porosity despite a sensible setting, measure the flow at the nozzle and check the whole gas line for leaks.
What is a nozzle flow tube and how do I use it?
It is a simple test tube that fits over the torch nozzle so you can see how much gas is really coming out at the point of welding. You press the torch trigger without striking an arc, read the flow from the tube, and compare it with what the flowmeter shows.
It is a quick way to find leaks, blockages and wrong settings without welding a test piece. It suits MIG and TIG torches, and it is worth checking after changing a hose, a torch or a nozzle.
Why does a carbon dioxide regulator sometimes need a heater?
When carbon dioxide leaves a cylinder and expands, it gets very cold. At higher flows this can freeze the regulator, and the flow then becomes unsteady or stops altogether, which spoils the weld.
A regulator heater warms the regulator body to prevent this. It is an electrical device, so check that its voltage matches your supply, keep the cable and plug in good condition and away from sharp edges, and follow the maker's instructions. For light or short jobs it is not always needed, but it is worth having for long welds or high flows.
What are cylinder quick connectors and when are they useful?
A quick connector fits between the cylinder and the hose or flowmeter and lets you connect and disconnect the gas without a spanner. They are common with small and portable cylinders, where cylinders are changed often and speed is useful.
Some are fixed-flow types set to a particular flow rate, and others are variable. Check the marking and the instructions for the gas, the flow range and the cylinder type. As with any gas fitting, check the connection for leaks after you make it, and keep it clean and free of oil.