The second stroke - compression. When the compression piston upward from the bottom dead center dead center, the stroke of the function there are two, one is to increase the air temperature, fuel combustion to prepare themselves: two to create conditions for gas expansion work. When the piston up, after the intake valve is closed, the air inside the cylinder is compressed, with the small volume of Shandong Province, East China ship machine services, air pressure and the temperature will continue to rise Weifang Huadong ship machine, the end of the compression pressure and Humidity and air compression related, i.e. the compression ratio, generally pressure and compression end temperature: Pc = 4 ~ 8MPa, Tc = 750 ~ 950K. Diesel auto-ignition temperature of about 543-563K Shandong East China Ship Suppliers, the compression end temperature than diesel fuel self-ignition temperature is much higher, enough to ensure the fuel injected into the cylinder of self-ignition combustion. Diesel fuel injected into the cylinder is not immediately angry, and physical and chemical changes after only angry, this time there are about 0.001 to 0.005 seconds, called the ignition delay period. Therefore, to dead center before the start of the atomization of the fuel injected into the cylinder at 10 ~ 35 ° crank angle, and crank TDC after 5 ~ 10 ° when the combustion chamber reaches the maximum combustion pressure in the crank Go, forcing downward movement of the piston. Different seasons should use different grades of oil. Some diesel bush-burning, because summer is the use of small viscosity oil in the bush can not form a film due to the contact surface. Weifang Huadong ship machine vendors _ Shandong East China (Online) _ Weifang Huadong ship machines by Weifang Huadong Engine Co., Ltd. Weifang Huadong Engine Co., Ltd. (www.hdchai.com) is an industry leader in Shandong Weifang, the internal combustion engine, over the years, the company implement the scientific management, innovation and development, the principle of honesty and trustworthiness, and satisfy customer needs. Weifang Huadong leadership with the staff warmly welcome all inquiries negotiations to create a better future Weifang Huadong.