Generally speaking, the repair procedures for diesel generator set cylinders are: boring and grinding cylinders. When the cylinders are so boring that they can no longer be boring, or when the boring conditions are not available, the cylinder liners are replaced or fitted. So today, Starlight Power Generation Equipment focuses on the inlay and matching process of the thousand-type cylinder liner of the diesel generator set.
1. Select the cylinder liner. When the diesel generator set cylinder is lined for the first time, the standard size cylinder liner should be selected to facilitate multiple lining repairs in the future. The outer surface roughness of the cylinder liner should not exceed 0.80m; the cylindricity tolerance should not exceed 0.02mm, and the outer edge of the lower end of the cylinder liner should have a corresponding taper or chamfer.
2. Boring the bearing hole. According to the selected outer diameter of the cylinder liner of the diesel generator set, bore the cylinder to the required repair size and surface roughness. If the original cylinder is inlaid with a cylinder liner, use a special tool to pull out the old cylinder liner, or use a boring machine to bore it. There are two commonly used tools for pulling and pressing cylinder liner, hydraulic type and mechanical type. Figure 3-24 shows the tool for mechanically pulling and pressing cylinder liner. After the old cylinder liner is taken out, it should be checked whether the bearing hole of the cylinder liner meets the requirements. The fit of the cylinder liner and the bearing hole should have appropriate interference. Generally, the fit interference of the cylinder liner with the flange on the upper end is 0.05-0.07mm, and the fit of the cylinder liner without the flange is 0.07-0.10mm. The matching clearance between the flange and the bearing hole: the general cast iron cylinder liner is 0.25 ~ 0.40mm. If the match between the old bearing hole and the newly selected cylinder liner does not meet the requirements, the bearing hole should be rebored to the required size.
3. Press in the new cylinder liner. After cleaning the cylinder and cylinder liner of the diesel generator set, apply an appropriate amount of oil to the outer wall of the cylinder liner, insert the cylinder liner into a part of the cylinder, use a square ruler to align it, put a hardwood or soft metal flat backing plate on the upper port of the cylinder liner, and then Use a 5-10t press to slowly press the cylinder liner in. If there is no press, use a special tool for hydraulic or mechanical pulling and pressing of the cylinder liner to press it in. In the process of applying pressure, the cylinder liner should always be kept perpendicular to the upper plane of the cylinder block, and the pressure should be gradually increased. After pressing in for 30-50mm, it should be relaxed so that it can adjust the position of the cylinder liner naturally. If the resistance suddenly increases during the pressing process, it should be stopped immediately to find out the reason to prevent the cylinder wall from being squeezed. In order to prevent the deformation of the cylinder block of the diesel generator set, when pressing the dry cylinder liner, the method of pressing the cylinders in sequence should be adopted.
4, trim the plane. After the cylinder liner of the diesel generator set is pressed into the bearing hole, its end face shall not be lower than the upper plane of the cylinder block, nor shall it be higher than 0.10m. When it is higher, it can be trimmed with a file, or the higher part can be flattened with a fixed cylinder boring machine.
5. Brush plating of cylinder liner. When the cylinder liner bearing hole of the diesel generator set is enlarged and a suitable cylinder liner cannot be matched with it, the method of brushing and plating the outer wall of the cylinder liner can be used to repair it. For brush plating, nickel baths and copper baths can be used. When multi-layer plating is used, the thickness of the plating layer can reach 0.29mm, which can meet the needs of the interference fit between the cylinder liner and the cylinder wall.
In most cases, the cylinders of diesel generator sets do not have the conditions for boring and grinding cylinders, and the maintenance cost will be lower by directly replacing or inserting cylinder liners. Therefore, when the wear degree of diesel generator set cylinders exceeds the technical conditions of use, The repair of the cylinder usually adopts the method of direct replacement or the above-mentioned inserting of the cylinder liner.
Starlight Power was founded in 1974 and is one of the earliest manufacturers of generators and diesel generator sets in China. If you want get more information, please feel free to send email to firstname.lastname@example.org we will pay highly attention on your question.