Connecting Safely
Valve operation : use care not force Open cylinder valve slowly (anti-clockwise) using the correct spindle key (obtainable from BOC Gas and Gear Centres - Part No 3637) or the handwheel fitted on some cylinders. Soft seat, spindle key operated cylinder valves (introduced into service in 1991) should not be subjected to excessive torque. Only use the correct spindle key. An opened valve should never be left against the backstop, but should be turned back at least half a turn to avoid seizure in an open position. When you shut the valve turn it clockwise and just enough to stop the gas completely. Never wrench it shut. (Remember all cylinder valve spindles have right- hand threads, unless they control flammable gases, in which case, they will have a left hand thread). If you stop work for more than a few moments, close the cylinder valve. Use acetylene cylinders upright If an acetylene cylinder has been transported horizontally, place it upright for as long as possible before using any gas: best results will be obtained by leaving the cylinder in an upright position for 12 hours. Do not use non-standard keys Never use anything but the recommended cylinder valve keys. Never increase the leverage of keys or use longer ones. Never use spanners with long handles; or even the correct key if it is badly worn. All of these could easily damage the valve seat or spindle square. If the valve spindle is too stiff to open by hand with the spindle key, return the cylinder to the supplier.
Look out for broken spindles If you think your cylinder valve has a broken or damaged spindle, do not try to get gas from it. Do not attempt to remove the gland nut; the broken spindle could be ejected or unwound at great risk to the operator - contact BOC Gases (Directline 0800 111 333). Always use equipment designed to take the gas pressure The gas cylinder and outlet valve are designed to supply gas through an approved pressure regulator. This pressure regulator screws directly into the valve outlet; this also applies to MCPs. Never install additional piping or fittings between regulators and the outlet valves of MCPs. Alternatively when individual cylinders of the same gas are manifolded together to a common outlet, the pressure regulator should be screwed into this outlet. Use needle or fine adjustment valves downstream of the pressure regulator only, never upstream. Pressure regulators: check the thread first Make sure the pressure regulator is designed for use at the pressure in the cylinder and that the threads are the same as on the valve outlet (5/8 in. BSP cone recessed in most cases). Never force any connection that does not fit. Regulators should be regularly maintained in accordance with the manufacturer's instructions. Do not attempt to repair or modify the regulator. Release the screw before fitting pressure regulator Before fitting a pressure regulator on to a full cylinder always screw out the pressure adjusting screw so that there can be no flow through the regulator when the cylinder valve is opened. Do not use oil or packing on any regulator - oxygen or not Never try to ease any regulator threads with oil: do not use PTFE tape. This advice applies to ALL gas cylinders and regulators. Never pack out or use any connection that appears worn when tightening or loose when fully screwed home. Fuel gas (Hydrogen, Propane, Acetylene): use only the regulator designed for the gas Do not interchange left hand threaded pressure regulators between gases. Each is designed for use with a specific gas, and to interchange them could be hazardous. Remember the cylinder pressure and properties are different for each gas. Do not use left hand to right hand adaptors. Fit flashback arrestors To prevent flames travelling back into cylinders, devices known as flashback arrestors should be fitted downstream of pressure regulators in oxygen, acetylene, propane and hydrogen systems. Does your manifold have the right regulators and flashback arrestors? Where cylinders are connected to a manifold or header the system must be properly designed for the task and installed by a specialist engineer. It must be fitted with one or more pressure regulators. Acetylene manifolds must also be fitted with a flashback arrestor.
Use a non-return valve with mains gas When using mains gas, the law states that a British Gas (BG) approved non-return valve must be fitted.
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