Vibration and noise on board

Diesel engines generate vibration during their operation . With each flash, an unbalanced impulse is generated inside the cylinder, which is transmitted to the hull through the base of the engine.

Another source of vibration is the propeller . When the blades move, there are cyclical changes in the water pressure on the ship's hull above the propeller. In addition, when the water vortices break off the blade during its movement through the water, pressure fluctuations arise on the blade itself. The pulses are transmitted to the housing through the shaft and its bearings.

Vibration is amplified if vibration sources are in resonance with the natural frequency of vibration of the housing or its parts. This must be taken into account when designing.

Sources of airborne noise are the exhaust system, sound frequencies when flashing in cylinders, turbochargers.

A very high noise level in the engine room, it is created by working mechanisms. During their work, mechanics use special protective equipment - ear inserts ("ear plugs"), noise-isolating headphones. Headphones are another sign of a person involved in the engine room.

Cabins are usually well soundproofed, but vibration is still felt. However, a person, especially a sailor, is known to get used to everything.

Starting marine engines from scratch - step by step

Cases and situations are different. But even with a complete shutdown of all engines, no electricity, discharged batteries and the loss of all starting air, the crew should still be able to start the ship's propulsion systems from scratch. How can I do that?

A small compressor with a hand-crank motor clogs a small reservoir with compressed air. Sometimes it can even be done with a hand pump. This air is already enough to start the ship's generator. When electricity appears, you can charge the batteries and with a powerful compressor start to clog air into the starting cylinders of the main engine, and after a while start it up. This is how, step by step, from small to large, you can restore the operation of all ship systems. There is always a way out!