Exam Question

### (a) Weighted Cocks on Tank Sounding Pipes (4 Marks)
The primary purpose of a weighted cock fitted to a tank sounding pipe is to serve as a passive, automatic, and failsafe closing device to maintain the watertight integrity of the compartment through which the sounding pipe passes.
* **Principle of Operation**: The device consists of a valve or cock (typically a plug cock) connected to an operating lever with a heavy counterweight. The weight is arranged such that its gravitational force constantly acts to rotate the cock into the fully closed position. To take a sounding, the operator must actively hold the lever against the weight's force to open the pipe. Upon release, the weight immediately and automatically shuts the cock.
* **Safety and Regulatory Compliance (SOLAS)**: As per SOLAS regulations (Chapter II-1), sounding pipes that terminate in a space below the bulkhead deck (e.g., engine room sounding pipes for double bottom tanks) must be fitted with effective means of closing to prevent progressive flooding. The weighted cock is a simple, robust, and reliable mechanism that satisfies this requirement. Its self-closing nature eliminates the risk of human error, where an operator might forget to close a standard valve after use.