If the maximum combustion pressure and the pressure pr pt on pimetru in individual cylinders to be within the limits specified in the instructions of the builder for this mode, the load on diesel may be increased to 75% of nominal. If the values of these quantities at 75% strength load beyond the specified tolerances, you must control a diesel engine. Finally, marine diesel govern with the power and frequency speed close to nominal. Many of the settings required for the regulation of diesel, can be identified by the indicator diagrams or waveforms. The most accurate data obtained by processing the waveform data. However, apparatus for the removal of waveforms is complex and cumbersome, it is usually only used for special studies and tests conducted by research institutes or thermal lots of shipping companies. With the daily operation for the regulation of marine diesel engines typically use charts, shot an indicator of power. This method is simple, accessible and sufficiently accurate for practical purposes.
The contour of the indicator diagram shows the change in gas pressure in the cylinder diesel engine, depending on the stroke. Area of the diagram corresponds to the work that is produced gases in the cylinder in one revolution of the crankshaft. For the indicator diagrams, withdrawn, subject to the conditions necessary indexing, we can define the indicator power of the engine and make the necessary distribution of the cylinders, to investigate the mechanism of gas distribution, fuel pumps and injectors, identify weaknesses and eliminate them, as well as to detect the fault of the ship's engines (gas passes through the piston o-rings, incorrect installation of the compression chamber, etc.). However, the judge of the existence and nature of the malfunction in the engine and its distribution in the body only if the known shape of the diagram, which can be taken as normal. Considered normal, such diagrams for which all points of distribution (intake, compression, fuel and combustion, expansion, release, and purging) are carried out without deviation from the rules provided for in the design of the engine. Deviation from the normal contour diagram indicates the presence of defects in the engine. Keep in mind that the distortion indicator diagrams may be due not only to violations of the distribution and wear some 'parts of the engine, but also secondary causes unrelated to his work (fault indicator or actuator, inept shooting diagrams, etc.). In connection with this regulation before the engine should check the indicator, it drive indicator valves and tubes and if necessary, to address deficiencies.