Install and Remove Piston Connecting Rod of Diesel Generator

Basic structural principle of piston connecting rod of diesel generator set

The piston connecting rod is one of the main moving parts in the diesel generator set. Care must be taken when disassembling the piston connecting rod. When changing parts, pay attention to the structural differences of each model, otherwise it will cause adverse consequences.

The piston is made of eutectic silicon aluminum alloy. The basic diesel generator sets have different piston structure differences. When changing the piston, pay special attention to the valve pocket depth dimension and the piston pin hole to the piston top surface distance dimension. Otherwise, the piston may be related to the cylinder head or The valve collides, causing a serious accident, or causing the compression ratio to drop and fail to work properly.

The piston skirt is a finished surface that prevents knocking when disassembling. There are 4 small holes of 5mm on the piston pin seat for lubricating oil splashing. The inner pin of the piston can be reused to adjust the weight of the piston set. Marked for use by the user when installing or replacing a new piston. The difference in weight of each piston in the same diesel generator set should be no more than 10g.

Reminder: During maintenance, a small area of scratches on the top of the piston, burn marks or slight damage to the skirt, can be used after repairing with a scraper and oil stone, otherwise it should be replaced.

Diesel generator piston rod self-assembly points

Some customers will choose to assemble themselves after the diesel generators are purchased. So today, Starlight will talk about the assembly of the piston rods in detail. The following are some of the points listed by the staff for your reference.

1. Press-fit connecting rod copper sleeve. It is best to use a press when installing the connecting rod copper sleeve, or by means of a vise. Do not use a hammer to strike; the oil hole or oil groove on the copper sleeve should be aligned with the oil hole on the connecting rod to ensure lubrication.

2. Assemble the piston and connecting rod. When assembling pistons and connecting rods, pay attention to their relative position and orientation.

3. Cleverly loaded with piston pins. The piston pin of genset and the pin hole are in an interference fit. When installing, the piston should be evenly heated to 90 °C ~ 100 °C in water or oil. After taking out, put the tie rod in the proper position between the piston pin hole, and then install the piston pin coated with organic oil in the given direction. Into the piston pin hole and the connecting rod copper sleeve.

4. Piston ring installation. When installing the piston ring, pay attention to the position and sequence of each ring.

5. Loading the link set.

Under normal circumstances, regardless of the distance, diesel generator manufacturers will be responsible for the assembly work of everyone, manufacturers who are unable to provide this service need more careful contact and inspection, so as to avoid cooperation errors.

Assembly method of diesel generator set piston connecting rod set

The piston connecting rod group is mainly composed of a piston, a piston ring, a piston pin and a connecting rod. Its assembly is an important part of the assembly process of diesel generator sets, so what is its assembly method?

1. 1. When replacing the connecting rod, measure the weight of each connecting rod of the same diesel generator set. On the basic diesel generator set, the weight tolerance of the connecting rod components is 30g (the tolerance for the diesel generator set used for the calibration speed >1500r/min is 20g).

2. The piston of the diesel generator set is heated to 100-120 ° C in the oil, and the piston is taken out, and the piston pin coated with the oil on the outer surface is loaded into the small hole of the piston and the connecting rod in time. At this point, attention must be paid to the relative position of the valve pocket at the top of the piston and the large head cutout of the connecting rod. The 4-6 cylinder in-line diesel generator set is shown in Figure 1; the 12-cylinder V-type diesel generator set is shown in Figure 2. After the piston is installed, install the piston pin lock spring with a pointed clamp (as shown in Figure 3).

3. Install the piston ring, you can use the wire ring sleeve (as shown in Figure 4), the piston ring is expanded to just pass the top of the piston, but it should not be too large to prevent the piston ring from breaking. When installing the screw spring oil ring assembly parts, first install the spring sleeve ring groove and then install the oil ring ring so that the spring is fully embedded in the inner groove of the oil ring ring, and the spring interface is placed opposite the oil ring ring opening. After the position is installed, the openings of the piston rings should be shifted by about 120° in sequence, and there should be no jamming in the ring groove.

4. Apply sufficient cleaning oil to the matching surfaces of the piston rod connecting rod, cylinder liner and crankshaft of the generator set, then place special tools for the piston on the cylinder liner, turn the crankshaft, and connect the connecting rod journal of the piston connecting rod. Turn to the 70 ° or so after the top dead center, and then carefully insert the piston rod into the cylinder liner (as shown in Figure 5). When installing, pay attention to the large cut surface of the connecting rod (with the pairing mark) should face the lower window of the body on the same side. Finally, the genset piston is pressed by hand, so that the inner circle of the connecting rod big head bearing and the connecting rod journal fit.