The exhaust system of the generator set must collect the gas in the engine cylinder and discharge it as quickly and quietly as possible. It must minimize back pressure, which leads to a loss of horsepower and an increase in temperature, thereby shortening the service life of the engine.
Several factors affect the performance of the exhaust system. Building restrictions, noise control, condensation, vibration, heat dissipation and building codes must be considered.
Exhaust pipe
Each generator set must be equipped with its own exhaust system. Connecting or sharing exhaust lines increases the chance of smoke entering idle engines or equipment, exposing them to corrosive gases.
Specify Schedule 40 piping. Its heavy construction suppresses vibration and resists corrosion by condensation. To minimize the back pressure at the bend of the exhaust system, use a 90-degree bend with a radius of at least one and a half times the diameter of the pipe.
When the system is at operating temperature, the weight exerted by the exhaust pipe on the engine should not exceed 37 kg (60 lb).
Flexible connections are required to alleviate vibration fatigue of exhaust system components. They also prevent vibrations from spreading throughout the building and can solve misalignment problems during installation.
Long pipes require flexible connections to provide heat growth. For example, a 6m (20 ft) steel exhaust pipe heated to 510°C (950°F) at 30°C (100°F) will add 33mm (1.3 in). Similarly, pipe supports must allow for heat growth.
Consider insulating pipes. Burning one liter of fuel in a diesel engine can produce up to one liter of water vapor. Insulation helps keep exhaust gases in a gaseous state and reduces the amount of heat radiated into the generator room.
Install a longer horizontal exhaust pipe, away from the engine and sloping slightly downward. The trap should be located at the lowest point of operation so that the condensate can be discharged.
Consult your engine manufacturer or its dealer for correct exhaust specifications.
Muffler/muffler
When installed as close to the engine as possible, the silencer provides optimal sound attenuation and minimizes pipe vibration. Like pipes, silencers should be mounted at an Angle and equipped with condensate discharge outlets.
There are many grades of mufflers to choose from. Since noise levels vary by engine model, rating, and distance measured from the exhaust port, use engine manufacturer data and muffler performance data to ensure adequate silence for your application.
Building exhaust port
Piping should be installed with a clearance of at least 229 mm (9 in) from combustible materials. High-temperature insulation or prefabricated insulation sections can be used above the pipe to protect against head radiation. Piping through a wooden wall or roof requires a single-wall metal thimble shield 305 mm (12 in) larger than the diameter of the exhaust pipe. Double-walled metal casings must be 153 mm (6 in) larger than the pipe diameter. Thimbles must comply with National Fire Protection Association Bulletin NFPA-110 and local building codes.
Both horizontal and vertical exhaust chimneys should extend above or away from the building. Horizontal pipe outlets should be oriented away from prevailing winds and cut at a 30 to 45 degree Angle to reduce gas turbulence and resulting noise. Vertical chimneys require a rain cap that exerts little back pressure and can be forced open by venting. In all cases, chimneys should be kept away from building air intakes.
Post time: Dec-21-2023