Valve Products from Weir Power & Industrial

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1 Rotary Gate Valve Leaders in critical control and isolation solutions Excellent Engineering Solutions Valve Products from Weir Power & Industrial

2 Introducing Weir Power & Industrial A proven track record Weir has extensive references and a proven track record in the supply of valves across a number of key industries Our valves are industry renowned brands, each with an established reputation for quality, engineering and reliability Valve testing All pressure containing items are hydrostatically tested, seat leakage tested and functionally tested We can also perform gas, packing emmission, cryogenic and advanced functional testing, as well as seismic testing for nuclear applications Material testing non-destructive examination by radiography, ultrasonics, magnetic particle and liquid penetrant Chemical analysis by computer controlled direct reading emission spectrometer Mechanical testing for tensile properties at ambient, elevated and sub-zero temperatures Aftermarket solutions Our valve aftermarket solutions are based on our engineering heritage, applying our OEM knowledge and expertise to maintenance strategies, life extensions and upgrade projects Quality assurance Weir is qualified to industry standards and working practices including: ASME BPVC Section III (N and NPT Stamp) ASME BPVC Section VIII (UV Stamp) NQA- Quality system CFR App B CFR RCC-E RCC-M CSA Z99 QTT 8 Performance testing and qualification to: ASMEQME- ASME B IEEE IEEE IEEE 8 ISO 9:8 ISO ISO PED 9//CE API Q TO API LICENCES API D (D-8) API A (-) TUV-AD MERKBLATT WRD HP ATEX 9/9/CE Lean manufacturing practices A- D-8

3 Weir purpose built valve facility at Elland, UK Above: Manufacturing facilities at Elland Left: Valve testing Contents Valve testing facilities All pressure containing items are hydrostatically tested, seat leakage tested and functionally tested In addition, gas, packing emission, cryogenic, hyperbaric, flow and advanced functional testing can be arranged Design Features Chemical Injection What is Cavitation? Valve Testing & Qualification RGV -

4 ROTARY GATE VALVE From Concept to Operation The rotary gate valve offers a new concept in fluid control and isolation for subsea and topside applications The valve was originally designed to continuously dose regenerated MEG for the Ormen Lange project where there was a particular problem with hydrate formation The valve was developed in conjunction with Statoil Hydro in Norway and went through an extensive qualification testing programme before being installed subsea Weir originally had the concept for the valve, but the concept was refined after an approach by Statoil Hydro to develop the valve for MEG dosage Statoil Hydro had particular problems with regenerated MEG blocking and damaging choke valves and the company was looking for an alternative valve design to minimise the level of subsea intervention Weir took the original concept idea and refined the operation through an extensive testing and development programme The valve is now operating successfully subsea on the Ormen Lange and Greater Gorgon projects In the words of the Statoil Hydro engineers the MEG provides the lifeblood for the gas extraction The valve is capable of operating with high differential pressures, flow rates and debris in the flow medium Design Features Adaptable for isolation, chemical injection and control/choke throttling Proven quarter turn technology No displaced volume or cavity and therefore the valve does not block due to debris or hydrates Straight through design means no bends to cause instability in the flow Unique gate design gives increased capacity over conventional valves using the same size orifice RGV Installed on the choke module before going subsea Seat and sealing technology is based on proven through conduit gate and ball valve technology Valve is a sealed unit with no atmospheric leakage Valve is manufactured from high integrity specialised materials in accordance with project requirements Virtually zero hysteresis Alternative mounting arrangement in the choke module RGV -

5 ROTARY GATE VALVE Flow orifice During the development cycle of the valve it was discovered that by profiling the bore of the orifice, flow rates could be increased through the valve while minimising the rate of erosion through the bore Specially profiled flow bore Flow Rate (m^/hr) Jansz Jansz Flow From Valve Against Differential Pressure Chemical Injection Features Continuous flow through the valve, there is always an orifice uncovered Accurate control of dosing though quarter turn manual or hydraulic actuator Wide rangeability of dosing flow rates Single stage of pressure drop through the valve giving higher flow rates (other valves on the same application require multi-stage pressure drops) High tolerance to impurities and abrasion using specially profile d tungsten carbide inserts Can be used as a secondary flow meter with differential pressure ( P) measurement Can have multiple orifices in the flow area to increase the range of flow control options The specially profiled flow orifice controls cavitation through the valve Any impurity or contaminant in the process fluid up to the size of the orifice in use will pass through the valve Flow Control Flow control is achieved by the specially profiled flow orifices Each bore is sized to give a crossover in the controlled flowrate As the orifice is rotated into the flow bore then this allows for a change in flowrate The control orifices can also be positioned so that multiple orifices are positioned in the flow bore to increase the rangeability of the valve Gorgon Flow Rate (m^/hr) Flow Rate (m^/hr) Gorgon Flow Rate (m^/hr) M/Day Typical 8 orifice flow profile Gorgon - Typical orifice flow profile Shut in DP (Bar) Typical 8 orifice high flow, low differential pressure flow profile Max DP Single orifice (P) Inlet Pressure Vapour Pressure (Pv) Flow From Valve Against Differential Pressure Ormen Lange Orifice FLOW RATE ( M/HOUR) Ormen Lange Orifice PRESSURE DISTRIBUTION 8 Combined Orifice Typical orifice flow profile Caviation elimination as no pressure recovery occurs across the rotary gate valve Outlet Pressure (P) 8 + Caviation fromation due to + pressure Combined recovery above the + Orifice + vapour Combined pressure Orifice in a typical +8 control valve FLOW RATE ( M/HOUR) FLOW RATE ( M/HOUR) FLOW RATE ( M/HOUR) Multiple orifice 8 Typical combined orifice flow profile RGV -

6 ROTARY GATE VALVE Chemical Injection Chemical injection is required on wells to prevent hydrate formations that, if left untreated, would block up the process system Hydrates are an ice like lattice structure caused by hydrocarbon vapour bubbles crystallising when the gas phase (containing entrained water) is depressurised Process blockages can occur for the following reasons: Loss of inhibitor Under injection Joules Thompson effect Low temperatures below the mudline Hydrate blockage Hydrate formation can cause the valve to become inoperable and when installed subsea then intervention can be very costly MEG is used to inhibit the expected water content in the hydrocarbon at a given well head pressure, in order to eradicate hydrate formation in the gas production line Essentially MEG is an antifreeze, and when used for gas extraction must continually flow in order to prevent system blockages What is Cavitation? Cavitation is a phenomenon that can occur in control valves on liquid service duties In its most severe form cavitation can destroy a valve trim in a matter of hours It is therefore important to control the level of cavitation Cavitation occurs in liquid systems when local pressure fluctuations near the liquids vapour pressure result in the sudden growth and collapse of vapour bubbles (cavities) within the liquid Conventional control valves are designed to reduce a higher inlet pressure to a lower outlet pressure As the inlet pressure (P) passes through the valve, and exits the trim, then if the pressure drops below, and then rises above the vapour pressure (Pv) then these cavities are formed The cavity collapse produces a localised shock wave and liquid microjets If these impact on the metallic surface of the valve then severe pitting and erosion damage can occur Cavitation often produces high levels of noise and vibration across a broad range of frequencies Excessive vibration can loosen flange bolting, damage piping support structures, and destroy process equipment The hazards of excessive noise can create dangerous conditions for people and their environment Cavitation Under Control The rotary gate valve is unique in controling the very conditions that create cavitation Pressure Distribution Valve Trim Area Hydrate Formation Pressure RGV Control Valve Vapour Pressure Cavitation Formation The potential for cavitation is reduced due to the profiled flow orifice High levels of pressure recovery are eliminated across the vena contracta of the valve which ultimately means that the static pressure across the valve never drops below the vapour pressure and therefore the very conditions that can cause cavitation cannot physically exist during typical operating conditions RGV -

7 ROTARY GATE VALVE Valve Testing and Qualification The rotary gate valve, during the development phase, was extensively tested to ensure reliability of subsea operation These tests included: Capacity tests using various inlet types Pressure distribution tests Cavitation test Erosion test Factory acceptance test Hyperbaric static test for hour duration Hyperbaric dynamic test for cycles Endurance testing for cycles These tests have been performed to cover three seperate sets of field design conditions to date (Ormen Lange, Jansz and Gorgon) Flow testing in Norway Actuation The rotary gate valve when located subsea is fitted with a hydraulic actuator to offer accurate positional control The hydraulic actuator features: Seats and Seals Problems due to fluid contamination in the rotary gate valve are kept to a minimum Whereas alternative designs of valve have plugs or needles moving within cavities, then any movement of those parts leave a vacant space which could lead to particulates becoming trapped This could reduce the flow, leading to blocking or sticking of the valve On the rotary gate valve, the disc turns within its own volume and therefore there is no cavity in which process contamination can become trapped Ultimately, this means that even with high levels of particulates in the process flow, the valve will The valve seats provide a metal to metal face seal operate through its full turning angle During operation the seats are energised by the line The pressure valve seats and provide push against a metal the to metal faces of face the seal disc affecting During operation a leak tight the seal seats Any are increase energised in by the the line pressure line pressure ensures and a push stronger against seal the faces of the disc affecting a leak tight seal Any increase in the line The valve body seal is achieved by a metallic duo pressure ensures a stronger seal seal The duo seal gives leak tight closure to both internal The valve and body external seal is pressure achieved by a metallic duo seal The duo seal gives leak tight closure to both Further seals are located on the central drive shaft internal and external pressure These seals are used to prevent fugitive emissions from Further the seals valve are shaft located On conventional the central rising drive stem shaft valves These seals as the are valve used plug to prevent is lifted fugitive out of the emissions valve then this from will the wear valve the shaft valve On packing conventional eventually rising leading stem to valves excess as the live valve emissions plug from is lifted the out valve of the The valve design then of this the will seals wear used the on valve the packing rotary gate eventually valve effectively leading means to excess that live the emissions valve virtually from the emission valve The free design of the seals used on the rotary gate valve effectively means that the valve is virtually emission free Compact & Concentric design, field proven technology Mechanical override via ROV / by-pass valve Integrated hydraulic control system / module Electric Control module LVDT Positioner / Control Valve EPP Fully redundant control system available Accuracy < +/- degree & linear output torque Fully pressure compensated Controlled either by inbuilt module (EPP) or direct from SCM Performance verification CDI OptiPak & OptiVee T seal Vector Duo Seal PTFE Lip seal Location of the valve seals RGV -

8 Weir Valves & Controls UK Ltd Britannia House Huddersfield Road Elland, West Yorkshire HX 9JR England Tel: + () 8 Fax: + () 8 info@weirpowerandindustrialcom wwwweirpowerindustrialcom Excellent Engineering Solutions RGV - Weir Valves & Controls UK Ltd, all right reserved