Crank shaft diameter of axle wear after repair

Crank shaft diameter of axle repair in 2019 - after wear 07 - 14 when diesel engine run some years later, the crankshaft main trunnion or crank pin diameter of axle may lead to wear and tear. A shipowner in ship repair and found auxiliary engine crank pin diameter of axle excessive wear, then through certain sales way to purchase a second-hand pieces, a professional company in the wear of the crank pin diameter of axle please take way to restore the original size of metal coating, then supply to install and use on the ship. Attached figure 1 unfortunately after about half a year, owner's email from claims that the lubricating oil filter found metal scrap, further examination found that auxiliary 3 # crank pin diameter of axle surface metal loss damage ( See figure 1) , and put forward the claim. Supplier to find the original metal coating manufacturers, professional institutions detection is put forward, but the manufacturer if the test results prove to be the coating of the metal loss, only agreed to free coating again. And owners could not accept this kind of coating again, to claim the whole new crankshaft, the price does not poor. Chart 2 suppliers in line with the responsible attitude to customers, send professionals in ship by domestic port of embarkation do check, check the name and seal on the crankshaft, and then provide consistent. For the whole crankshaft made a comprehensive inspection, found only 3 # crank pin diameter of axle surface metal loss damage, its corresponding 3 # crank shaft bearing damage ( See attached figure 2) , other parts are found no damage or anomalies, crank pin for all five cylinder trunnion were measured, and only 3 # crank pin diameter of axle is smaller than other crank pin diameter of axle was 0. The diameter of the 27 mm, other crank pin diameter of axle are nearly the same. Look carefully damage surface and the test results, according to the size can clearly determine damage caused the original metal coating fall off. At the same time, the fusion of metal on the busbar took the sample and bring back the damaged bearing, so that necessary component analysis to determine whether the coating of the metal. In fact, for the crankshaft trunnion after wear, should take measures for the repair of more reliable with small size, English name is undersize, is according to the actual size of crankshaft after trunnion wear ( Less than the original size) , and then a corresponding matching small size of bearing bush, of course, undersize narrow size range in the diesel engine model allows range. Using metal coating method to restore the original size, there is a huge risk, this process is reliable and practical at the same time the coating and the adhesion strength of the original forging steel material enough, it depends on the surface cleaning workers operating temperature control, and so on a series of factors, in a word, the repair method is not preferred. For intermediate suppliers, absolutely not directly involved in the business trade, it is not independent enough of trade disputes, or even losses. （ Author: miller ab. hoogstraten b Shanghai thinks that watch possess. you network/Shanghai information technology co. , LTD. Technical director)