Diesel engine bearing don't know how to choose watching this at 3 o 'clock will know - bearing knowledge

Today to share repair diesel generating set, the selection and collocation of work before. Bearing selection and collocation: one, the old bearing identification if bearing quality is good, the suitable size, repairing method is correct, use in good condition, can be used for long period, but in the diesel engine overhaul, bearing must be replaced. Found in diesel engine repairs or repair, such as bearing is in one of the following circumstances will not continue to use. 一个。 Shaft and bearing fit clearance is too large, and unable to adjust. b。 Bearing surface has crack, alloy fall off or have serious mark, even the tile burning. c。 Bearing alloy thin at 0. 2mm。 d。 Elastic failure, loss of roundness than the normal range ( < 0 diesel engine. 07mm） 。 Second, the quality requirements of the new bearing a. Both ends of bearing should be higher than that of bearing 0. 05mm（ As shown in figure 3 - 83) b。 Bearing no sand holes, muted, crack and coarse on the back. c。 Anchor point positioning is good. d。 Bearing oil hole for as far as possible, the error must not exceed 0. 5mm。 e. The same pair of bearing two pieces of thickness difference should not exceed 0. 05mm。 Three, the new bearing size matching tests to determine when to replace new bearing, shall, first of all, the main journal and the surface of the connecting rod journal, such as loss of roundness and conical degree back to normal, and then press the crankshaft journal and the journal of actual size to choose and adapt to the new bearing. General crankshaft main journal and the size of the repair of connecting rod journal are: standard and reduce size. Diesel engine has 6:0. 25, 0. 50, 0. 75, 1. 00, 1. 25, 1. 50, every narrow 0. 25 mm for level 1. So, when replace new bearing bush, according to the main journal and existing dimension of connecting rod journal to matching the corresponding bearing shell, namely the journal is a standard size, be about to choose a standard size of bearing, shaft neck is narrow, should be selected according to journal repair size bearing at the same level. Visible in bearing many aspects need to be paid attention to when the choice, must according to oneself the circumstance of bearing to take different solutions.