Tham khảo tài liệu 'cummins engine shop manual part 2', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | PARTS CHECKING INSTRUCTIONS Insert the gauge into the bore to be measured and read the minimum indication of the test indicator while giving swings to the gauge about the tip of the detachable rod used as the fulcrum. When the minimum reading is obtained on the right side of the zero point of the test indicator and the reading to the standard value to which the zero point is set. When the minimum reading is obtained on the left side of the zero point subtract the reading from the standard value. PARTS CHECKING INSTRUCTIONS Check disassembled parts to see if they are reusable or need repair. If the part failed due to an external source determine the cause and correct before assembly. 1. GENERAL PRECAUTIONS Visually inspect parts for cracks pitting corrosion scoring ridging etc. To ensure proper inspection every part should be clean before inspection. If the cause of the defect can be found it will be a great help to analyze the part condition whether the defect will progress or not and the possibility of future trouble. Knowing the cause of the defect the service man can give good advice to the customer to prevent him from having the same trouble again. Visual inspection can not find minute or hidden damage. Other methods of inspection are as follows a Water-pressure or air-pressure test b Color check or magnetic damage test 3. PITTING 1 Pitting by cavitation In most cases cavitation is accompanied by chemical corrosion. After removing rust or scale carefully inspect the depth of pitting. When the pitting can not be repaired within the allowable limit replace the part. If pitting is not deep resurface the part after removing the rust and scale. 2 Pitting due to removal of surface If ball bearing is pitted replace it. If more than 1 3 of the contact face is pitted the part should be replaced. If pitting is not serious resurface the part. 2. CRACKS If the part is found to be cracked by visual inspection it should be replaced or repaired. If the length or depth of .
