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The German standard flanged ball valve adopts the ball valve produced and inspected according to the German standard, which belongs to the best performance among many ball valve series products. Many customers who have purchased German standard flanged ball valves have given this valve high praise. However, there are also some customers who report the failure of the German standard flanged ball valve. So for users, why are there still some failures with such good performance of the German standard flanged ball valve? This is generally caused by the untimely maintenance of the ball valve. Let Xiaobian introduce some installation and maintenance instructions for German standard flanged ball valves.