ANDERSON GREENWOOD. Provides reliable overpressure protection in a cost effective package. Flow Control

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1 ANDERSON GREENWOOD Provides reliable overpressure protection in a cost effective package. Product Overview Anderson Greenwood s LCP Series pilot operated safety valve is designed to provide the reliable overpressure protection you have come to expect in a cost effective package. The compact assembly lends itself to supplying larger capacities that optimize the entire pressure relief valve installation. The LCP Series valve has the capability to be used on almost all gases or vapors. The valve is available with inlet sizes of 1 to 3 [25 to 75 mm], set pressures from 25 to 2220 psig [1.72 to 153 barg], and continuous temperatures from -20 to 400 F [-29 to 204 C]. The scope of the LCP Series design is fixed upon these common sizes and set pressures, and comes equipped with typically required accessories as a standard. In fact, the only available option for the LCP Series valve is a trim for sour sulfide laden gases. This latest edition to our POPRV line provides dependable safety in a low cost configuration. Features and Benefits Rigid Pilot Mounting. No tubing anywhere on the valve provides ultimate protection against vibration and careless handling. Balanced Design. Proper valve operation and lift are unaffected by back pressure. Costly and fragile metal bellows are not required. Integral Back Flow Prevention. High superimposed back pressure or inlet vacuum will not open valve. Added protection and safety at no added cost. Flow Control Non-Flowing Pilot. Minimizes entrance of dirt or hydrates in the pilot to provide repeatable performance during multiple relieving cycles. ASME Section VIII Code Stamp. Certified third party capacities for gas service. Viton Soft Seats and Seals. Reduces emissions and product loss while minimizing maintenance costs. No metal seat lapping is required. Full Bore Orifices. Reduces upfront valve and associated piping costs. Integral Field Test Connection. Standard feature that provides a safe and accurate way to do in-place performance tests. NACE MR Trim (2002 Edition). Optional trim materials available to meet sour gas requirement. Anderson Greenwood is either a trademark or registered trademark of Tyco International Services AG or its affiliates in the United States and/or other countries. All other brand names, product names, or trademarks belong to their respective holders. Total Flow Control Solutions -US-0504

2 Operation Pilot To Main Valve Dome Backflow Preventor Dome Piston Seal Piston System Pressure Main Seat Normal Closed Position Figure 1 Backflow Preventor Pilot Exhaust Relief Seat Blowdown Seat System Pressure Back Pressure U.S. Patent Number 6,161,570 Relieving Position 2

3 Sizing Data Sizing Formulas English Units Metric Units V MTZ A = 6.32 C K P 1 K b V MTZ A = C K P 1 K b ASME Orifice Areas Valve Size Orifice Area in [mm] in 2 [cm 2 ] 1 x 2 [25 x 50] [5.06] 1.5 x 2 [40 x 50] [11.40] 2 x 3 [50 x 80] [20.27] 3 x 4 [80 x 100] [45.61] Nomenclature Symbol Description English Metric Units Units A Calculated orifice area in 2 cm 2 V Required capacity SCFM Nm 3 /hr M Molecular weight T Relieving temperature ( R = F or K = C + 273) R K Z Compressibility factor C Gas constant (if unknown, use C = 315, see Table A) K ASME nozzle coefficient (90% of actual) = P Set pressure psig barg P 1 Inlet flowing pressure (P + allowable overpressure - inlet pressure loss + atmospheric pressure) psia bara P 2 Outlet flowing pressure psia bara K b Back pressure correction factor Cp k Ratio of Specific heats ( k= ) C v Back Pressure Correction Factor 1.00 k = 1.0 Coefficients of Discharge ASME Nozzle Coefficient of Discharge for 90% of Actual Capacity Gases/Vapors K = k = 1.6 k = 1.8 k = 1.2 k = k = 2.0 Back Pressure Factor, Kb P 2 /P 1 = Absolute Pressure Ratio at Valve Outlet 3

4 Specifications Table A - Gas Constant, C k C k C Natural Gas Capacities (SCFM, 10% Overpressure, 60 F, 90% of actual, Z = 1.0, 0.60 SP Gravity) Set Pressure 1 x x 2 2 x 3 3 x 4 (psig) in in in in

5 Operation In the normal, closed position, full system pressure is sensed through the bottom of the main valve piston. When the system pressure is higher than the back pressure, the integral backflow preventer (BFP) is sealed towards the discharge of the valve. This allows the system pressure to pass through the center of the main valve piston. The system pressure then enters into the dome (volume above the main valve piston). The main valve remains closed because the piston seal area is greater than the main seat area. If the back pressure exceeds the system pressure, or if the valve senses a vacuum, the BFP is then sealed towards the valve inlet, as shown in Figure 1. This allows the higher back pressure to enter into the dome and keep the main seat closed. When the pilot senses set pressure, the relief seat snaps open and the blowdown seat snaps closed simultaneously. This vents the dome pressure safely to atmosphere through the vent in the main valve cap. This allows the main valve to open fully at set pressure. The blowdown seat remains tightly closed during the relief cycle so no system fluid continuously flows through the pilot. When the main valve reduces the system pressure to a level below set pressure, the relief seat snaps closed and the blowdown seat snaps open simultaneously. This fully repressures the dome to system pressure and closes the main valve. The reseat pressure is not adjustable but will provide an average of 15% or less blowdown as shown below. 100% Lift Down Force on Main Valve Piston Main Valve Piston Lift 15% Average Blowdown Closing Opening 0 Set Pressure 0 Set Pressure Recommended Soft Goods Limits Material Continuous Pressure Process Range Temperature psig [barg] F [ C] -20 to to 2200 Viton [-29 to +205] [1.72 to 153] L18 Ordering and L19 Information Specifications Valve Model Numbering Valve Inlet Size 04 1-inch inch 08 2-inch 12 3-inch LCP N Valve Inlet Flange # RF # RF # RF # RTJ Note 1. Viton is a registered trademark of the E.I. dupont de Nemours Company. Valve Trim Option Blank Standard Trim N NACE Trim (2002 Edition) 5

6 Tyco Flow Control (TFC) provides the information herein in good faith but makes no representation as to its comprehensiveness or accuracy. This data sheet is intended only as a guide to TFC products and services. Individuals using this data sheet must exercise their independent judgment in evaluating product selection and determining product appropriateness for their particular purpose and system requirements. TFC MAKES NO REPRESENTATIONS OR WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION ANY WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE WITH RESPECT TO THE INFORMATION SET FORTH HEREIN OR THE PRODUCT(S) TO WHICH THE INFORMATION REFERS. ACCORDINGLY, TFC WILL NOT BE RESPONSIBLE FOR DAMAGES (OF ANY KIND OR NATURE, INCLUDING INCIDENTAL, INDIRECT, OR CONSEQUENTIAL DAMAGES) RESULTING FROM THE USE OF OR RELIANCE UPON THIS INFORMATION. Patents and Patents Pending in the U.S. and foreign countries. Tyco reserves the right to change product designs and specifications without notice. 6