2.1 standard pneumatic valve body material quality, should be ductile iron, steel, stainless steel valves, Shandong, 316L-based, and indicate the grade and cast actual physical and chemical test data. 2.2 valve stem material, and strive to stainless steel stem (2CR13), large diameter valves should also be embedded in the package of stainless steel stem. 2.3 Material Z641F pneumatic valve nut vendors, with cast brass or aluminum bronze, and the hardness and strength are greater than the stem. 2.4 stem bushing material, its hardness and strength shall be not greater than the stem, and is immersed in water conditions and valve body is not the formation of electrochemical corrosion. Pneumatic valve is a device in the factory manual should indicate the following data: Valve specifications; Model; working pressure; manufacturing standards; body material; Stem material; sealing material; valve shaft packing material; stem sleeve material; internal and external corrosion Material; Operation Starting direction; hoist pressure in the working condition moment;; factory Make revolutions; the date of manufacture; serial number; weight; connecting flange apertures, number of holes, the center of the pitch; the manner shown marked overall length, width and height of the control dimension; valve flow resistance coefficient; effective opening and closing times; valve factory testing of the relevant data and installation, maintenance precautions. 1.1 General Requirements pneumatic valve specifications and categories, shall meet the requirements piping design documents. 1.2 pneumatic valve models should be specified in accordance with the requirements of GB number. If the enterprise standards, instructions should indicate models. 1.3 pneumatic valve job pressure ≥ pipeline working pressure, without affecting the price of the premise, the valve can withstand working pressure should be greater than the working pressure of the pipeline actual pneumatic valve; pneumatic valve is closed on either side of situations should be able to withstand 1.1 times the value of the working pressure valve without leakage; under the valve open position, the valve should be able to withstand twice the working pressure valve requirements. 1.4 Weifang valve pneumatic valve manufacturing standards, should explain the basis of the national standard code, if the file should be attached to business enterprise standards, procurement contract. Z641F pneumatic valve Sellers | gate valve | valve manufacturers Everbright Everbright Limited provided by Shandong valve. Valve Co., Ltd. Shandong China Everbright (www.sdgdfm.com) strong, credible, Shandong Weifang ball industry has accumulated a large number of loyal customers. The company better work attitude and constantly improving innovative ideas will lead Everbright valve into the brilliant and you work for a better future!