Worm gear clamping type metal hard seal butterfly valve Product Description Note: 1.Design Manufacture According to GB/T 12238-1989 2.Face to Face According to GB/T 12221-2005 3.End Flange Dimension According to GB/T 9113-2000 4.Valve Check and Test According to JB/T 9092-1999 Detailed Images Functions Company Information Packaging & Shipping Contact way
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