SMM, April 23: the current contract of electrolytic copper in North China today rose by 270 yuan / ton to 350 yuan / ton, and the transaction price was 42000 yuan / ton to 42350 yuan / ton. Shanghai copper rose to 42000 yuan / ton, rebounding more than 1000 yuan / ton. The northern smelter centralized maintenance, the smelter shipment is limited, the northern electrolytic copper is tight, the market rises the water to raise the price again, the highest rises the water 350 yuan / ton, the rising water average price increases 20 yuan / ton compared with yesterday.