Upper bearing detaching tool of diesel engine main bearing and detaching method

Abstract

The invention discloses an upper bearing detaching tool of a diesel engine main bearing. The upper bearing detaching tool of the diesel engine main bearing comprises an arc-shaped guiding plate and ahandle. A thickness of the guiding plate is smaller than a thickness of an upper bearing. An arc length of a circular arc is smaller than a semicircular arc length of a positioned circle. A horizontally installed handle support block is fixed on the peripheral face of the middle of the guiding plate, and adjacent to one end of the guiding plate. The other end of the guiding plate is provided witha positioning screw hole. One end of the handle is vertically and fixedly connected with the handle support block through a thread, and locked through a nut. A detaching method comprises the followingsteps: 1) assembling the guiding plate; 2) enabling the guiding plate to be positioned on the lower part of a crankshaft journal; 3) rotating a crankshaft to eject the upper bearing; and 4) reverselyrotating the crankshaft to take out the guiding plate. The upper bearing detaching tool is capable of skillfully using rotation of a short arc edge to push out the upper bearing clamped between the crankshaft journal and the main bearing, improving detaching efficiency of the upper bearing, and solving a problem that the upper bearing is detached without damaging a bearing surface.

Description

technical field The invention relates to a maintenance and disassembly tool for a bearing bush of a diesel engine, in particular to a tool and a method for taking out a bearing bush on a main bearing of a diesel engine, and belongs to the technical field of diesel engine maintenance. Background technique The crankshaft of the medium-speed diesel engine is mostly forged as a whole. It is supported on the frame by several main bearings arranged at intervals. The main bearing adopts the structure of upper and lower bearing bushes. The surface of the inner arc is coated with a wear-resistant layer. During the operation of the medium-speed diesel engine, the lubricating oil forms a load-bearing oil film between the crankshaft and the bearing bush, so that the crankshaft is always in a suspended state supported by the load-bearing oil film during operation, thereby protecting the crankshaft journal. The surface roughness of the working surface of the bearing bush is above 0.4, an...

AI Technical Summary

Problems solved by technology

The upper and lower bearing shells need to be removed during main bearing maintenance, and the lower bearing shell can be removed together with the main bearing cover, which is relatively easy; while the upper bearing shell 10 is sandwiched between the crankshaft shaft diameter 20 and the main bearing seat 30 as shown in Figure 1, and it is difficult to disassemble

Especially during the disassembly process of the upper bearing bush 10, its working surface must not be damaged in any way, otherwise it will directly cause the bearing oil film on the crankshaft shaft diameter to fail to be established.

When the shaft diameter of the crankshaft lacks the bearing oil film support, there will be dry friction between it and the bearing bush, which will cause serious accidents such as cylinder scuffing and locking in a short time

At the same time, because the upper bearing bush itself has a certain weight, and its disassembly operation space is extremely small (especially the first and last two gears), during the disassembly process of the upper bearing bush, it is difficult to ensure that the tile surface of the upper bearing bush is not damaged, and the disassembly is laborious and laborious low efficiency

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