Lubricated Plug Valves Type 20 & 21

About this product

Some useful news concerning Lubricated. Plug Valves Material /Costruction. In order to meet with Int'l Specifications and various Customers' needs, Valvitalia is producing Lubricated Plug Valves suitable to cover the widest applications. Executions • Lubricated Inverted Taper Pressure Balanced High Performance Plug Valves. • Lubricated Inverted Taper Pressure Balanced High Performance Materials Application. All DVE Products are normally available in: • Standard Carbon Steel which are supplied in 0,22% MAX Carb. contents, and destined to General Service at Temperatures from - 29° C Up to + 232° C (- 20° F% + 450° F). Plugs are normally in Carbon Steel too, in Hardened Condition. • Low Temperature Service Suitable from - 46° C to + 232° C (- 50° F% + 450° F). Normally used for Below Zero. Temperatures to - 46° C must have a Minimum Average Charpy "V" Notch Impact Strength a/15 Foot/Lb. • In Natural Gas it is Possible to encounter small amounts of Hydrogen Sulfides (H25) which may cause corrosion. This phenomenon is normally known as "Hydrogen Sulfide Embrittlement" or "Sulfide Stress Cracking". The Absorbtion of Hydrogen from Part of the Steel Causes Ductility which, when added to other elements of stress given by the service itself, may originate failure of the forged or cast component. Steels with Yield Strengths above 621 Mpa (90.000 PSI) or with Hardness over 22 Rockwell (235Brinell) may be subject to "Sulfide Stress Cracking". In Nace MR01.75-88 Construction DVE is carefully checking that all basic material componentes are propely treated in order to remain below the Hardness of 22 Rockwell. In such a case, plugs are property Electro Nickel Coated to prevent galling action. • Stainless Steel material which contains Molybdenum and suitable for service temperature from + 232° C to + 371º C (+ 450° of % 700° F) normally used for Valves destined to High Temperature Service or where High Corrosion resistance is needed. • 13% Chr. - 316 - Monel (Solid or Coating) Stellite No.6 (Coating) • Special material available on request. Lubricated Steel Plug Valves Pressure Balanced Inverted Type. These valves are installed where existing pulsant or static high pressures are present. The benefit which a pressure balanced Plug gives is the equalized pressure between the Plug and upper and lower body chambers. Pressure is balanced by two holes in the Plug connecting the Plug port with lower and upper cavities. The hole in the lower end is a simple connecting passage whilst the hole in the upper end is provided with a check valve so the pressure is always equal to the one in the large end cavity and it is always equal to or greater than the line pressure in the small end cavity. Some advantages are: • Easy maintenance even after a long time in open/closed position • In case of locking of the Plug with the body, it is possible to release by injecting lubricant through the greaser with the valve in service • Tightness of the stem is assured by an antifriction ring fitted between the stem and body. Two gaskets fitted between the stem and valve body garantee against any leakage through the stem. • Tightness of the operating system is assured by the ball check devices on the lubrication duct. An adictional check valve is put into the lubrication duct. • When required the valve is equipped with double operating grease injectors suitable for a lubricating gun and lubricating sticks. Wrench Operated Class 150 Short Pattern Wrench Operated Short & Venturi Pattern Gear Operated Short Pattern Wrench Operated Venturi Pattern Gear Operated Type 20 Class 400 Regular Pattern Wrench Operated Venturi Pattern Gear Operated Regular Pattern Wrench Operated Regular and Venturi Pattern Gear Operated Class 600 Screwed or Socket Weld Ends Wrench Operated Class 800 Screwed or Socket Weld Ends Wrench Operated Regular Pattern Wrench Operated Regular and Venturi Pattern Gear Operated Type 20 Class 1500 Regular Pattern Wrench Operated Regular and Venturi Pattern Gear Operated Screwed or Socket Weld Ends Wrench Operated Class 2500 Screwed or Socket Weld Ends Wrench Operated Type 20 Class 2500 Regular Pattern Wrench Operated Regular Pattern Gear Operated Extension Stem for Wrench and Gear Operated Lubricated Plug Valve for buried Installation. Extended stems are made to be installed on Wrench Operated standard stems, in case of buried installation of the Plug Valve or in case of installation of the valve in plant locations where a normal access of manouvre is not possible. Valve extension for underground service include piping for lubrication and are supplied with water tight seals. Extension length should be advised by customer. As already described in case of Wrench Operated Valves, these extesions are suitable for Plug valves with gear operators. The extension stem is similar to the previous one. The position of the Plug is indicated by an indicator on the top of the gear box. Valve extension for underground service include piping for lubrication and are supplied with water tight seals. Extension length should be advised by customer.