Crankcase blow-by gas is produced when combustion gases under high pressure escape past piston rings into the crankcase. As these blow-by gases pass though the crankcase, they become contaminated with oil mist. In enclosed areas, like generator sets or engine rooms, the contaminated gas coats and damages surrounding equipment, resulting in hazardous conditions and the need for costly maintenance. Uncontrolled blow-by oil mist also coats engine after-coolers and turbochargers, which reduces cooling capacity and engine efficiency. Crankcase Ventilation Systems prevent this problem by removing mist and contamination in blow-by gases. In closed systems (CCV), the high efficiency filter prevents fouling of the turbocharger and after-cooler. In open systems (CV), it prevents fouling of surrounding equipment and walls, thus allowing clean exhaust to vent directly to the atmosphere. The systems have stainless steel latches for tool-less element change and a metal housing steel , aluminum an epoxy powder coating components. They also have a drain check valve, which allows collected oil to return to the crankcase, resulting in drastically reduced oil consumption. Open systems are acceptable for certain engines and situations. However, in recent years, environmental concerns and legislation to control crankcase emissions have increased significantly. New laws to further reduce the total emissions of engines often make it necessary to close the crankcase breather system. In this case, blow-by gases are routed into the inlet of the turbocharger where they can be burned instead of polluting the environment.
How they work: CV Series (Open Crankcase Ventilation Systems) CV (open) system filters are high-efficiency oil separators, featuring depth-loading, micro-glass fiber media, which is capable of coalescing vapor and contaminants down to 0.3 microns. The resulting filtered and coalesced oil is held in a hose line with a check valve until it can be released to the oil pan via a hose connection. Filtered gasses are released to the atmosphere. The units are designed to handle crankcase flow rates up to 50 cfm (1,42 m3 /m) or more when using multiple units. CCV Series (Closed Crankcase Ventilation Systems) - CCV (closed) systems also utilize depth-loading, micro-glass fiber media. In these systems, blow-by gasses are not allowed to vent to the atmosphere. Instead, the cleaned and filtered gases are routed back to the inlet of the turbocharger to be burned in the engine. The units are designed to handle crankcase flow rates up to 50 cfm (1,42 m3 /m) or more when using multiple units. CCV units feature a unique crankcase pressure regulator with an integral bypass valve. This regulator protects against crankcase over-pressure and under-pressure, thus preventing damage to seals and oil loss. Use in Marine Applications - Marine diesel engines can benefit from the installation of a combination CCV and air filter/silencer system. The CCV contains high-performance filter media. Marine air filter/silencers (AF Series) contain washable media and are ruggedly built to provide extended service life.
When installed, the engine crankcase breather is connected to the inlet of the CCV Assembly. The CCV outlet is connected to the engine's combustion air inlet via an air intake connector where filtered blow-by gas is recycled through the combustion process. Oil collected in the CCV sump is returned to the crankcase through a hose and a drain check valve.