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Type P1808 Pilot-Operated Gas Pressure Relief Valve

Type P1808 Pilot-Operated Gas Pressure Relief Valve
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Type P1808 Pilot-Operated Gas Pressure Relief Valve - 1

P1808 Pilot-Operated Relief Valve or Backpressure Regulators The P1808 pilot-operated relief valve or back pressure regulator is used in gas or liquid service to maintain pressure on oil and gas separators, and in pressure relief applications in gas distribution systems. The function of the P1808 is controlled by the type of pilot installed on the unit. A PL82 series pilot regulator is used in back pressure applications, and only bleeds when repositioning the main valve. A PL82B series regulator is used in pressure relief applications, and exhausts the entire time the inlet pressure is above the set pressure. This allows the unit to achieve wide-open flow more easily. The unit controls pressures from 3 to 125 PSIG (0.21 to 8.6 Bar), and the set pressure can be adjusted for individual requirements by the adjusting screw on the pilot. Applications • Gas or Liquid Service • Gas Separators • Distribution Relief Device Features • Compact Design • Pilot Operated Body, Bonnet, Diaphragm Case • High Flow Capacity P1808 Part Matrix P1808 16 2" NPT Standard Output Pressure Ranges 3 to 18 PSIG 15 to 40 PSIG 35 to 125 PSIG Regulator Setup Back Pressure Regulator Relief Valve Accessories None Gauge Filter Filter and Gauge Pilot Trim Material Nitrile (NBR) Upstream Control No Yes Body Material 0 Cast Iron (Standard) 2 WCC Steel 1808 Body Diaphragm Plates and Diaphragm Casings Diaphragm O-Rings Gaskets Backup Rings Spring Valve Plug Guide Cast Iron or WCC Steel Zinc-plated steel Nitrile (NBR) Nitrile (NBR) Nylon Polytetrafluoroethylene (PTFE) Zinc-plated Steel (Standard) Stainless Steel PL82 Series Pilot Body Aluminum Spring Case Aluminum Body Plug Aluminum Valve Plug Nitrile (NBR) Spring Zinc-plated Steel Diaphragm Nitrile (NBR) or Fluorocarbon (FKM) Spring Seat Zinc-plated Steel Stem Guide Stainless Steel Adjusting Screw Zinc-plated Steel O-Rings Nitrile (NBR) or Fluorocarbon (FKM) Closing Cap Aluminum Connector Cap Stainless Steel Mounting Parts Tubing Stainless Steel Fittings Stainless Steel Pipe Tees Galvanized Steel Pipe Nipples Malleable Iron, Galvanized Steel and Stainless Steel Options Upstream control line construction Pressure gauge (0 to 160 PSIG / 0 to 11.0 BAR / 0 to 1.1 MPa) P590 Series Pilot Supply Filter Approximate Weights Type 1808 22 pounds (10 kg) 1

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Type P1808 Pilot-Operated Gas Pressure Relief Valve - 2

P1808 Flow and Sizing Coefficients Flow Coefficients (Wide-Open) P1808 Capacities1 Using Internal Control Line and a Pilot with High-Gain Restriction Capacity in Thousands of SCFH (Nm3/h) of 0.6 Specific Gravity Natural Gas Relief Pressure Setting Pressure Build-up in PSIG Over Relief Pressure Setting - Shaded areas indicate capacities with main valve wide-open. 1. Capacities based on 0 PSIG (0 BAR) outlet pressure. If outlet pressure is not 0 PSIG (0 BAR), shaded capacities may be recalculated using the wide-open Cg and the desired pressure drop. P1808 Capacities Using Optional External...

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Type P1808 Pilot-Operated Gas Pressure Relief Valve - 3

P1808 Regulator Rebuild Kits Kit Includes Nitrile Diaphragm Assembly, Valve plug O-rings & backup O-rings, Casing/body gasket Part Number

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Type P1808 Pilot-Operated Gas Pressure Relief Valve - 4

Part Number Upper Casing, Steel Lower Casing, Steel Diaphragm Assembly Upper Diaphragm Plate Lower Diaphragm Plate Valve Plug, SS O-ring Retainer Bodies 2" NPT - Iron, Straight 2" NPT - Steel, Straight Valve Plug O-rings Valve Plug Base O-ring - Nitrile Valve Plug O-ring - Nitrile Valve Plug Backup Ring (2 required) Upper Valve Plug O-ring - Nitrile Spring Valve Plug Bolt Valve Plug Bolt Nut Part Number Casing Build Screws (12 required) Casing Build Screws Nuts (12 required) Casing/Body Build Screws (2 required) Casing/Body Build Screw Nuts (2 required) Valve Plug Guide Casing/Body Gasket...

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