VALVE AND CONTROL SYSTEM DTP CHOKE VALVE. Discrete Tortuous Path. Solution FOR SEVERE CHOKE APPLICATIONS

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1 VALVE AND CONTROL SYSTEM DTP CHOKE VALVE Discrete Tortuous Path Solution FOR SEVERE CHOKE APPLICATIONS

2 Solution FOR SEVERE CHOKE APPLICATIONS DTP DISCRETE TORTUOUS PATH CHOKE VALVES are designed to provide the highest level of quality and reliability for flow control applications under severe conditions, preventing the Cavitation and other risks related to the high fluid velocity altogether. ABV Energy has the capability to deliver complete valves for the major and most demanding Oil & Gas and Petrochemical projects throughout the world. Valves for severe service conditions are generally subjected to very high differential pressures and/or very low temperatures, thereby extreme care must be taken in order to avoid costly premature failures. Problems associated with these conditions are flow erosion of the valve body and trim, vibration and high noise. For these reasons, our mission is to provide engineered products that safely operate and deliver long term performance, having a low maintenance cost with a long life of the main internal components. 3D modeling and computational fluid dynamics simulations have been analyzed and studied by ABV Energy to assure valve performances throughout its entire life. DTP CHOKE ADVANTAGES: Improved plant performance Reduced leakage costs Higher reliability Lower noise Longer intervals between maintenance Reduce maintenance & down time, meaning no interruption to production Reduced system costs Lower installation costs 24 hour support & worldwide locations

3 INTERNATIONAL STANDARDS Valves are sized, designed, manufactured and tested in accordance with: API 6A ASME VIII Division 1&2 ASME II ASME B16.05 ASME B16.10 ASME B16.25 ASME B16.34 ISA ISA ISA VDMA ANSI/FCI 70-2 ISA IEC MAIN APPLICATIONS In Oil & Gas and Petrochemical production, transmission and processing, including LNG service, with focus on their common problems. High Pressure, Up Stream Valves Rules of Construction Materials Specifications Flange Standards Face to Face dimensions Long Pattern (customized on request) Buttwelding Ends Design rules for flanges, threaded, and welded end Cv Terminology Flow equation for sizing control Valves Inherent Flow Characteristics Noise Prediction Level Control Valve Seat Leakage Control Valve Capacity Test Procedures Control Valves STD OIL & GAS WELLHEAD CONTROL Continuously operated over the life of the field Wellhead fluids pressure drop range from 700 Bar (10,000 psig) at startup to 1 Bar (15 psig) years later High sand Content High noise level High Vibration Presence of multi-phase fluids WATER INJECTION High Pressure Drop High cavitation potential, especially at the start-up High rangeability, often required GAS INJECTION High Pressure Drop High Vibration High rangeability, often required SEPARATOR LEVEL CONTROL Sandy service High cavitation potential Dissolved gasses may flash Corrosive environment DTP Choke Valve are suitable for several types of fluids and aggressive environments like: Corrosive and Sour (H2S), (material in accordance with NACE MR 01-75) Abrasive and Oxygen Service, Slurries and solid suspension in gases and air, Vapour (including steam), whether clean or dirty, Multi-phase Fluids.

4 DESIGN PHILOSOPHY The design principle of DTP is to control the flow velocity by controlling the pressure losses across the valve. A single high pressure drop, across the valve, produces an unsteady system without any possibility to control the output flow velocity, whereas dividing it in several stages, a reduction of the velocity is possible, thereby reducing the risk of premature failures related on cavitation and erosion. DTP Valves are traditional robust angle valves ( globe type available on request) with a multi stage cage and its corresponding plug, specifically designed to provide a high energy dissipation. Multi Stage Cage consists of a clamped stack of disks having a multiple set of tortuous paths in parallel to each other, used to increase the flow resistance through the trim. This decreases the overall velocity through the valve, thereby reducing the pressure recovery. Typically, discrete tortuous path uses a series of right 90 angle turns to create frictional losses and to slow down velocity. Each turn reduces the velocity by one velocity head, thereby the velocity inside the trim can be calculated as following: V= 2 SG V H N WHERE: V= required velocity SG= specific gravity V H =pv 2 /2 velocity head N= number of turn Flow Flow Trend of pressure through a 6 Turn Path Trend of velocity through a 6 Turn Path

5 The reduction of the velocity is the predominant factor to avoid the risk of erosion. Erosion rate will vary as a third to fifth power function of the velocity. Discrete Tortuous Path design protects the trim from premature erosion, increasing the trim life many times. ABV Energy provides trims with two different Discrete Tortuous Path typologies: ETCHED OR LASER DISCRETE TORTUOUS PATH for an horizontal direction flow. THROUGH DISCRETE TORTUOUS PATH for a vertical and horizontal flow direction with disks made from a through space plate. For compressible fluids in addition to the velocity control through the right hand turn, the tortuous pathways can be enlarged, allowing the expansion of the flow. Etched tortuous path Through tortuous path INHERENT FLOW CHARACTERISTIC LINEAR: All the disks in the stack have the same number of passages and turns, and the same flow area; the flow is directly proportional to the valve stroke at a certain differential pressure. MODIFIED EQUAL-PERCENTAGE : Disks can be different. The number of the passages, the turns and flow area are varied according to precise calculation in order to satisfy the following rule. A change in flow per unit of valve stroke is directly proportional to the flow occurring just before the change is made. VELOCITY REQUIREMENTS Inlet fluids velocity and internal trim velocity have to be limited to minimize the valve body erosion and to avoid the potential risk of instability and vibration of the system. In case of Liquid Service, the DPT multistage configuration assures an output flow velocity equal to the inlet flow velocity. In case of Gas Service, the flow velocity through the DTP multi stage cage must be limited depending on the requested acceptable Sound pressure level (SPL). SPL <85 dba 85 dba<spl <95 dba Velocity through the trim must be less than 0.3xMach Velocity through the trim must be less than 0.5xMach Sound Pressure Level (SPL) is estimated in accordance with VDMA 24422, thanks to our dedicated sizing program. For more information about the SPL and our program, please ask to our Sales Department.

6 SIZE 1-12 PRESSURE CLASS ASME API TEMPERATURE RANGE -60 C to 200 C QUALITY TEST LEVEL PSL 1; PLS2; PSL 3 and PSL 3G on request STANDARD LEAKAGE CLASS FCI-70,2 Class IV, V others on request VALVE CHARACTERISTIC Linear Modified Equal-Percentage ACTUATOR Pneumatic Spring return/ Double Acting Hydraulic Spring return/ Double Acting Electric Pneumatic Stepper 6 Note On request, wide availability of materials depending on the customer specifications. 9 2 ITEM 1 Body COMPONENT 7 2 Bonnet DTP Multi Stage Cage 3 4 Seat Ring 4 5 Plug 6 Stem 7 Gasket 8 Seal 9 Bolting

7 Solution FOR SEVERE CHOKE APPLICATIONS MAIN DESIGN FEATURES Standard forged body construction in accordance with API 6A, ASME B Bolted Bonnet with metal to metal for enhanced VALVE SIZE TRIM SIZE CV STANDARD safety and easy maintenance. Body gallery sized for optimizing the flow capacity 1 1/2 5 inside the body. Stack of the disks is clamped without any internal threads and can be installed without any special tools. Plug and trim are interchangeable in standard valve design. Plug and trim material with excellent erosion resistance property. Trim with large flow inlet ports, to easily allow to the solid and dirty particles to flow through. Balanced pressure plug to minimize the actuator thrust. Blowout proof stem design. Lip Seals for all dynamic and static seals to enhance / /2 2.1/2 1.1/2 2.1/ / reliability of valve. Globe type body available on request Note For valve size over than 12, please ask directly to our Sale Department For Special applications the Cv value will change in order to satisfy the operating requirements.

8 Apply advanced design technology to improve performance. VALVE AND CONTROL SYSTEM ABV ENERGY S.p.A. Via di Coselli, 13/ Coselli, Capannori - Lucca - Italy Tel Fax info@abvvalves.com - sales@abvvalves.com