Table of Contents
What is a piston cooling valve?
Piston cooling valves Piston cooling via oil spray reduces thermal loads and temperature gradients while the engine is hot. This is not necessary during warmup. The piston cooling valve can stop the oil spray for quicker warmup and also control the piston temperature during operation.
How does a piston cooling nozzle work?
To cool the pistons down and prevent overheating, engine oil is injected onto the pistons from below via the piston cooling nozzles. Most diesel engines have one piston cooling nozzle per cylinder. Thanks to the oil, heat dissipates, and the engine can operate safely.
What is piston oil cooling?
Cooling channels—The piston is cooled by oil flowing through a cooling channel or gallery incorporated into the piston. One or more oil spray nozzles feed oil into the cooling channel through inlet openings in the bottom of the piston. The cooling oil exits the cooling channel through one or more drain holes.
Why piston cooling oil is not drained to the crankcase?
i) The piston cooling water conveyance piston and attendant gear must be kept out of the crankcase as far as possible, due to the danger of contamination of the crankcase lubricating oil by water leakage. ii) The piston cooling space should be drained of water after the engine is shut down for an extend period.
Why is oil used instead of water for cooling pistons of a diesel engines?
Oil has a lower thermal capacity than water, so as piston cooling oil forms a part of the engine main lube-oil system, a larger sump will be required. It also has a lower maximum working temperature of 130°F so must be controlled below this to prevent the formation of carbon and lacquer on hot internal surfaces.
How hot do pistons get in an engine?
The slugs of aluminum inside your engine live in a fiery hell. At full throttle and 6000 rpm, a piston in a gasoline engine is subjected to nearly 10 tons of force every 0.02 second as repeated explosions heat the metal to more than 600 degrees Fahrenheit.
What is a piston oil squirter?
Piston cooling oil jets go by many names (oil squirters, piston squirters, piston jets, oil jets, etc.), but have a single function. They direct cool oil from the main oil feed to the underside of the piston to help remove heat.
Which parts of the diesel engine require cooling?
The typically components of the cooling system are:
- Water pumps.
- Heat removing device (radiator or heat exchanger)
- Coolant expansion tanks (surge tanks)
- Temperature control valves.
- Temperature and pressure switches and indicators.
- Pipes.
What are diesel pistons made of?
The piston transforms the energy of the expanding gasses into mechanical energy. The piston rides in the cylinder liner or sleeve as shown Major Components of a Diesel Engine. Pistons are commonly made of aluminum or cast iron alloys.
Why does my oil pressure drop at idle?
Low oil pressure at idle only, will most often mean that the engine is low on oil. As more power is applied to the engine via acceleration, the pressure builds up inside the engine. High oil temperature can cause low oil pressure. A defective oil pump can also lead to low oil pressure at idle.