Oilers/Plant Tenders (HHC) Civil Service Practice Exam

What is the approximate oil feed rate to a steam engine cylinder with a 10-inch diameter piston?

1. A pint every hour

2. A pint every 2 hours

3. A pint every 5 hours

4. A pint every 10 hours

The correct answer is: A pint every 5 hours

To determine the approximate oil feed rate to a steam engine cylinder with a 10-inch diameter piston, it is essential to consider the operational requirements and the size of the piston. The specified feed rate indicates the frequency and quantity of oil needed to maintain lubrication for optimal performance. A piston with a 10-inch diameter is considerably large and requires a sufficient amount of lubrication to ensure smooth operation and to minimize wear on the cylinder walls. The correct answer, which states a pint every 5 hours, reflects a balanced approach to lubrication, providing enough oil to maintain effective lubrication without flooding the engine or causing excessive oil consumption. This rate likely accounts for the needs of the steam engine's operating conditions, such as temperature and speed, while still ensuring that the moving parts are adequately lubricated over an extended period. Thus, a pint every 5 hours is an appropriate figure for such a machinery scale, supporting continuous functioning without overwhelming the system with oil. When considering the other rates, such as a pint every hour or every 2 hours, these would likely result in excessive oil consumption, leading to potential issues like oil leakage or buildup. Conversely, a rate of a pint every 10 hours might be too sparse, risking inadequate lubrication and increased wear on the components.