火室

火室は蒸気機関車 に於いて、ボイラー 内の水 を沸騰させるために、燃料 を燃焼させるための空間です。
火室は、一部がボイラーの内部に入り込むように配置されています。
また、ボイラー内部を貫通して反対側の煙突付近まで伸びる煙管の集合体が取り付けられているのも特徴的であり、熱風と煙はそこを通過します。

Coal-powered fireboxes have a firedoor in the vehicle's cab , which can be opened to shovel coal inside. The door should be kept closed otherwise, to prevent blowback. Blowback is a dangerous event where exhaust flow is reversed, drawing fire into the cab, potentially catastrophically harming the crew. It happens upon entering tunnels with the firedoor open.

To ignite coal, use a lighter .

火室内の温度は、温度計で測定します。必要な量の蒸気を作り出すために、必要なだけの温度を保つ必要があります。温度が低すぎると蒸気が十分に出ず、高すぎると燃費が悪くなります。

Firebox temperature is controlled by the amount of coal and airflow inside it. Simply having no more coal to burn will cause the firebox to cool down, and adding more coal will warm it up if the airflow is sufficient. The amount of airflow is key, and depends on whether there is steam being admitted to the cylinders , but can also be adjusted by the blower and damper controls.

Having the firebox full to the brim with coal is not always the best choice. Too much coal with too little airflow negatively affects fuel efficiency , resulting in a lot of coal particles getting spewed out the chimney before fully burning. This is what makes the exhaust dark. When coal amount is proportional to available airflow, however, coal burns cleaner and the exhaust color is more bright.

火室内の石炭の量をより正確に制御するために、運転士は給炭量の少ないエキスパートスコップを使用できます。また、火室の焚口戸の隣にある石炭排出レバーを使用して、余分な石炭を捨てることもできます。

Coal in fireboxes can be dumped manually, with the coal dump lever found next to the firedoor.