Product Features:
1.Outside Screw and Yoke: The external side of the stem is threaded, while the section inside the valve is plain. Valve stem threads are isolated from medium by packing, which keeps the stem threads outside the valve body to avoid damage from high temperatures, corrosives, and solids within the valve. The external screw can be maintained from the outside, making it the preferred choice for demanding applications.
2.Body/Bonnet Connection: KAMROO gate valves are available with bolted and pressure-sealed bonnet, depending on its pressure rating or customer requirements.
3.Body/Bonnet Sealing: KAMROO offers stainless steel with graphite spiral wound gaskets for bolted bonnet gate valves in pressure rating Class 15 to Class 600, and Octagonal ring fittings as standard for bolted bonnet gate valves in pressure rating Class 900 and above. Pressure seal bonnet design are usually used for valve pressure rating Class900 and above to make it sealed. The common used material for the gasket is flexible steel ring or graphite.
4.Valve Stem Integral Forging Design: The valve stem adopts integral forging design, and the minimum diameter of the stem is as per AP1600. The connection between the valve stem and gate plate adopts T-head design, which is integrally formed with the valve stem. The accuracy in the dimension and surface assures a long service life with a perfect sealing in the packing area, resulting in lower fugitive emissions. The connection of the stem to the gate is designed to prevent the stem from turning or detaching from the wedge while the valve is in operation.
5.Stem Packing: Molded flexible graphite is used for packing material. PTFE or composite packing material can also be used according to customer requirements. The inner surface of the stuffing box has a high surface finish at the contact area with the packing. The surface of the contact between the valve stem and the packing has been precisely machined to achieve the required high finish and density, ensuring the reliable sealing of the valve stem.
6.Back Seat Design: KAMROO gate valves adopt the back seat design. In most cases, the carbon steel gate valve is fitted with a renewable back seat. For the stainless steel gate valve, the back seat is machined directly in the bonnet or after welding. The sealing of the back-seat is reliable when the gate valve is in a fully open position.
7.Flexible Wedge and Solid Wedge: Gate valve wedge is made for one integral casting piece, the commonly used types are flexible wedge and solid wedge. Flexible wedge can minimize stress concentration and its flexibility ensures tight sealing over a wide range of differential pressures and temperatures. It adapts to slight misalignment caused by pipeline deflection, pressure and temperature differences, as well as thermal deformation. The stem-to-wedge thrust is applied close to the wedge centre, which could reduces lateral stem loading and provides more accurate wedge movement. Solid wedge can provide a tight sealing action but it is prone to getting locked in position if there is a slight deformation in valve body due to thermal expansion or bending loads.
8.Replaceable and Integral Seat Design: KAMROO cast steel gate valves are available of both replaceable seat and integral seat design. Carbon steel gate valves are usually with replaceable seat ring either threaded with welding or welded on to body directly. For stainless steel and high temperature alloy steel gate valves, it is recommended that the valve seat is designed as integral valve seat or body sealing surface with hard surfacing welding.
