{"id":805,"count":3,"description":"The UKSPAR catalog presents valves with an eccentric for blocking water and air in large diameter pipelines. Cast iron models Fig. P101 PN10 and Fig. P102 PN16 are available, as well as Fig. P101-I with an electric drive. You can select DN in the cards and view the characteristics. To order, you need to determine the nominal passage, working medium, maximum pressure and temperature, tightness class and control method. UKSPAR specialists will help you check the compatibility of the valves with the project. The declared tightness class "A" is for the catalog models. The available DN range depends on the series: the required size should be checked directly in the product card or the current technical catalog.\r\n

How to choose a flanged gate valve with an eccentric<\/h2>\r\nFirst of all, the flanged valve with an eccentric is selected according to the diameter DN and pressure PN. The connection dimensions must correspond to the mating flanges, and the construction length to the location on the pipeline. The flow direction, temperature and sealing material are also taken into account. The control method depends on the diameter and the level of automation. The gearbox simplifies manual opening and smoothly moves the disc. The electric drive provides remote control. A pneumatic drive is advisable for fast cycles, but the possibility of its installation and the required torque should be agreed for a specific model. For an automatic drive, the supply voltage or control air pressure, operating time, degree of protection and the need for limit switches are additionally determined. It is important to provide a method of manual control in the event of a power failure.\r\n

Design and operating principle<\/h2>\r\nThe main elements of the valve are the body, the rotating disc, the stem, the seat, the seal and the actuator. Turning the stem a quarter turn brings the disc into the closed position: it presses against the seat and blocks the passage. The eccentric means that the axis of rotation is offset relative to the disc or the sealing plane. The contact with the seat is reduced over most of the stroke, and the pressing occurs at the end of the closing. This reduces friction and wear.\r\n

Double and triple eccentric<\/h2>\r\nThe double eccentric has two axis offsets. The disc moves away from the seat faster, so the seal rubs less and retains its properties longer. This solution is common in large DN water fittings. The triple eccentric adds an angular offset to the sealing surface. Contact with the seat occurs mainly during full closure, which allows the use of a metal seal in more complex modes. The type of eccentric of a specific model must be confirmed by the technical passport.\r\n

Housing and seal materials<\/h2>\r\nIn models P101 and P102, the body and disc are made of high-strength cast iron EN-GJS500-7, and the seals are made of EPDM. They are specified for water and air and temperatures up to +70 \u00b0C. The seals are always selected according to the composition and temperature of the flow. EPDM is well suited for aqueous media, but compatibility with specific impurities must be checked separately. The tightness and service life of the seat depend on the correct choice of elastomer. Steel and stainless steel are used in other versions of industrial valves, if the environment requires it. The material of a specific gate should be checked in its card.\r\n

Advantages of eccentric valves<\/h2>\r\nThe offset axis reduces friction between the disc and the seat, so the seal wears less. This maintains tightness, makes handling easier and extends the service interval. The 90\u00b0 rotation ensures quick flow shut-off. Benefits include:\r\n