Generally speaking, the maintenance procedure for diesel generator set cylinders is to enamel cylinders and grind cylinders. When the cylinder of the generator set can no longer be enamel or there is no enamel condition, replace or inlay the cylinder liner. In this article, we will learn 4 repair skills for diesel generator cylinders.
1. Diesel generator cylinder boring and cutting.
Reasonable selection of maintenance size: The maintenance size of diesel generator set cylinders is divided into six levels. On the premise of the standard size of the cylinder diameter, each increase of 0.25mm is a level, and it is further increased to 1.50mm. It can be seen from the cylinder damage permissible limit (0.35-0.40mm) and the maintenance size level that the enamel cylinder usually exceeds the first-level maintenance size, so +0.50mm.+1.00mm.+1.50mm is the most commonly used.
The selection technology of the cylinder maintenance size of diesel generator set is to estimate the wear diameter and machining allowance of the main cylinder (usually 0.10-0.20mm), and then select the main wear diameter + machining allowance of the main cylinder. Among them, the size of the machining allowance depends on the equipment and technical level. On the premise of ensuring the quality of the enamel, the machining allowance should be as small as possible. For example, there is an internal combustion engine, the standard cylinder diameter is 81.88mm, the machining allowance for most damaged cylinders is 0.20mm, the diameter is 82.49mm, 0.20+82.49=82.69mm, 82.69mm exceeds the third-level maintenance size. Therefore, the maintenance size of the enamel cylinder should be the fourth-level maintenance size + 1.0mm, and the fourth-level maintenance size should be 82.8mm after enamelling.
2. Correctly select the piston and piston ring of the diesel generator set.
After the maintenance dimension of the generator set cylinder is determined, the piston and piston ring of the same grade can be selected. According to the maintenance improvement of the cylinder, the backup piston of various machines is divided into six levels (+0.25mrn.+0.50mm.+0.75mm.+1.00mm.+1.25mm.+1.50mm).
When choosing a generator set piston, the following points should be paid attention to:
(1) The machine can only use pistons of the same level.
(2) Select the complete set of pistons produced by the factory (company) to make the material, performance, quality and size consistent, the diameter of the piston is less than 85mm, and the quality difference of the piston is less than 9g, the diameter of the piston is greater than 85mm, and the quality difference of the piston is less than 15g.
(3) The diameter of the top of the piston is 0.6~0.9mm smaller than the diameter of the skirt.
3. Accurately estimate the amount of boring.
At present, the selected diesel generator set piston enamel cylinder is usually used, that is, the outer diameter of the piston skirt is measured according to the repair size, and the enamel size of each cylinder is determined according to the actual size of the diesel generator set piston and cylinder.
Most of the diameter of the piston skirt - the minimum diameter of the cylinder + clearance - the margin of the grinding cylinder, that is, the amount of slush.
The size of the clearance between the piston and the cylinder is related to the diameter, material and structure of the cylinder. There are specific regulations for each model of internal combustion engine.
According to the precision of the grinding cylinder equipment and the technical level of operation, the grinding cylinder allowance should not be too large or too small. Too much time is wasted, and it is easy to cause the cylinder to lose its roundness and taper beyond the tolerance, the accuracy and cleanliness are too small, and the quality cannot be guaranteed, usually 0.03~0.06mm.
For example, the minimum diameter of the above-mentioned internal combustion engine to detect damage to the cylinder is 82.30mm (using the fourth-level maintenance dimension + 1.00mm, and most of the diameter of the first-level piston skirt is 82.88mm), using 0.03mm fitting clearance and 0.06mm grinding cylinder excess quantity, cutting quantity=82.88-82.03-0.06=0.55mm.
4. The cylinder of the generator set is machined and cut.
When enamelling the cylinder of the diesel generator set, the load-bearing times should be fully considered according to the allowable limit of the amount of knives each time. Generally speaking, the load of the first knife enamel is uneven due to the hardened skin layer of the cylinder surface and the loss of the cylinder ring. In order to ensure the roughness of the cylinder surface, the amount of the last knife should be small, usually about 0.05mm. After several inquiries, it can be larger, usually limited to 0.20mm, but not more than the amount of knives specified by the enamel machine.
Cylinder enamel is carried out by special enamel machine, usually including vertical enamel machine and mobile enamel machine. Enamel machines have different structures and methods of use. Take the domestic T-8014A mobile enamel machine as an example, as shown in figure 3-16.
Most of the performance from the T-8014 to the mobile boring machine are as follows:
Boring diameter: 65~140mm.
Most boring depth: 300mm.
Spindle speed: 250r/min.380r/min.
Spindle feed (passage): 0.11mm/r.
Most cutting depth: T≤o.5mm.
Guangxi Dingbo Power Equipment Manufacturing Co., Ltd. is one of the earliest manufacturers of generators and diesel generator sets in China. It has been established for more than 15 years in the country. The service department provides users with one-stop service of design, supply, debugging and maintenance at any time. Welcome contact us by email email@example.com