We assume that the supplied gas is methane (CH4). However, it is generally (maybe) approximately 85% methane. The balance is a combination of other hydrocarbon gases that will raise the calorific value of the gas to the agreed and supplied gas.
Safety is a critical issue with this gas. It is very highly flammable, and it will also explode violently with the correct combination of air and temperature.
Do not, repeat do not, attempt to put city gas into a furnace that is not above 1400°F, otherwise there is a very serious danger of a violent and sometimes catastrophic explosion.
Check that all of the safety solenoids are operating at both OPEN and CLOSE action of the solenoids. Also check that the main gas train from the incoming city gas pipeline is functioning correctly and that all of the pressure valves and pipe joints are not leaking city gas into the local area.
When you come onto a shift, take a walk about your furnace equipment area and use your senses.
- Look: Check the safety guards on drive systems, pipe connections, flame curtains, explosion-cap pilot lights, cleanliness around the furnace (no waste matter, oil spills, etc.) and check atmosphere flow meters to see that they are operating. Check water flow meters for water cooling of bearings and to assure water flow. Look for potential loose electrical connections.
- Listen: Listen to drive systems such as the circulation fan drive and the charge-car drive systems. Listen for unusual noises emanating from the furnace.
- Smell: Use your sense of smell to detect perhaps hydrocarbon gas or ammonia leaks. Be aware that you will not be able to smell such gases as nitrogen, argon, carbon monoxide, carbon dioxide or hydrogen.
When using the sample cut-off machine in the lab area, make sure that the abrasive cut-off wheel is an integral wheel and has not cracked or broken.
Make sure that the safety hood on the cut-off machine is functional and that it operates in a safe manner. Always keep the coolant sump of the cut-off machine clean and free of metal fines and wheel fragments and be certain it is treated with a bacteriological suppressant chemical. Bacteria can easily breed in an unclean sump.
Be sure that visitors to your facility are always accompanied by a responsible and authorized person, and that they do not touch anything because of its potential to be hot.