The main bearing of the crankshaft is selected according to the diameter grade of the crankshaft journal and the grade of the main bearing seat, and the main bearing is usually represented by numbers and colors. When using a new cylinder block and crankshaft
Check the levelness of the main bearing hole on the cylinder block and find the corresponding line in the main bearing selection table.
As can be seen from the figure, there are five A marks on the cylinder block, corresponding to the dimensions of the main bearing holes of no. 1~5 crankshaft from left to right at the front end of the crankshaft.
② In the main bearing selection table, select the kingpin neck diameter marked with grade in the column in front of the crankshaft.
Figure 4-18b shows the mark on the first counterweight at the front end of the crankshaft. The first letter corresponds to the first kingpin stage of the crankshaft, and the fifth letter corresponds to the fifth kingpin stage of the crankshaft.
③ Select the symbol of the intersection of the column and column in the main bearing selection table.
④ Use the symbol in the main bearing grade table to select the main bearing.
When reusing the cylinder block and crankshaft
① Measure the inner diameter of cylinder spindle tile and crankshaft journal respectively.
② Find the measurement size in the main bearing selection table.
③ Select the symbol of intersection of row and column in the main bearing selection table.
④ Use the symbol in the main bearing grade table to select the main bearing.
Post time: Mar-25-2022