Throught Conduit Gate Valves Slab and Expanding

About this product

Design construction: API 6D - ANSI B16.34 Testing according to API 6D Marking according to MSS SP25 Fire safe design according to API 6FA-BS 6755 part2 Outside Screw and Yoke (OS&Y) Floating seats with grease injector design 8" Back seat design Special packing with lantern ring and double ball grease injector Electroless nickel plated slab gate and seat Vent and Drain valve Full stellited seats and slab on request Body Bonnet seal Spiral Wound (S.S. plus graphite) or RTJ Other design at request Valves are Full Bore or Reduced Bore Flanges according ANSI B16.5 for size 2" to 24" to ASME B 16.47 for size > 26" Butt Welding Ends according to ANSI B16.25 Face to face according to API 6D Suggested bevel gear operator for: DN ≥ 20" Class 150 - DN ≥ 14" Class 300 DN ≥ 10" Classes 600 and 900 - DN ≥ 8" Class 1500 DN ≥ 4" Class 2500 For pressure and temperature rating see material application Valves are also available as expanding gate Through Conduit Gate Valves are designed in accordance with the latest applicable revisions of API 6D for classes ANSI ISO, 300, 600, 900, 1500 and 2500. The design is refered to the international standard code and is applied to verify all components and connections of the valve. The design of the stem is checked by applying the highest traction load caused by the slab gate which wins the reaction of the seats during the opening of the valve at full design Dp and at design temperature. Technical Department has performed traction load tests on stems at the Mechanical Engineering University Department of Padova - Italy to verify the stem material yield value and maximum allowable load according to ASME II Part D. The seat ring are floating type-spring loaded to assure the contact with the slab gate in a way to provide an effective tight seal even at low differential pressure between inlet and outlet flange. The soft seat insert assures the primary sealing and the metal contact between slab and seats is the secondary sealing. Different soft seat materials required by Customer's specification are applied depending on the fluid process. The metal to metal seat is designed and manufactured on request for application either with aggressive and dirty fluid or when operation at very high temperature occurs. As an additional request, the Through Conduit Gate Valves are designed with the expanded slab with the addition of a relief valve in the body cavity. On request Through Conduit Gate Valves are fitted with emergency seals to restore sealing in the event of soft seal damage. The fire safe design, if required, includes a supplementary sealing gasket (graphite) to avoid leakages in case of fire and burning of the soft seal as per BS 6755 Part 2 and / or API 6FA. EXCELLENT DOUBLE BLOCK AND BLEED CAPABILITY AUTOMATIC RELIEF OF EXCESS BODY PRESSURE With equal pressure throughout the valve and gate in closed position. An initial seal (1) is formed with the raised TFE ring on the faces of the seats. The seat inserts clean both sides of the gate each time the valve is opened or closed. Powerful springs assure sealing independent of high pressure, low pressure, or vacuum providing a constant contact during any type of operation. 2 As line pressure (2) is applied to the valve, it acts on the gate, forcing it against the seat ring on the downstream seat, a seal is formed (a the beginning a TFE-to-metal seal, then metal-to-metal). The O-ring (3) prevents any downsteal flow at this point. An upstream seal is provided when body pressure is bled off. This is caused by the force of line pressure acting against the upstream seat (4) moving the seat against the gate and providing a tight TFE-to-metal seal at this point.At the same time, the O-ring (5) forms a tight seal with the seat and body. 3 Valve automatically relieves itself of excessive body pressure. When body pressure exceeds line pressure, from such causes as thermal expansion, the upstream seat is forced back into its recess and the excess pressure in the body is bled between the seat and the gate into the line. Class ANSI 150 - Full Bore Class ANSI 150 - Reduced Bore Class ANSI 300 - Full Bore Class ANSI 300 - Reduced Bore Class ANSI 600 - Full Bore Class ANSI 600 - Reduced Bore Class ANSI 900 - Full Bore Class ANSI 900 - Reduced Bore Class ANSI 1500 - Full Bore Class ANSI 1500 - Reduced Bore Class ANSI 2500 - Full Bore Class ANSI 2500 - Reduced Bore On request