type aCe97 Pad-Depad valve • Bubble Tight Shutoff • Frictionless Pilot Valve • Pilot Controlled • Maximum Vapor Space Control • Stainless Steel Figure 1. Type ACE97 Pad-Depad Valve

Bulletin 74.3:ACE97 Specifications Pad Specifications General Type ACE97 Specifications Pressure Registration External Maximum Operating Inlet Pressure(1) 200 psig / 13.8 bar Temperature Capabilities Nitrile (NBR): -20 to 180°F / -29 to 82°C Fluorocarbon (FKM): 0 to 212°F / -18 to 100°C Ethylenepropylene (EPDM - FDA): -20 to 212°F / -29 to 100°C Perfluoroelastomer (FFKM): -20 to 212°F / -29 to 100°C Maximum Main Valve Inlet Pressure(1) 200 psig 13.8 bar Control Pressure Ranges(1) See Table 1 Maximum and Minimum Differential Pressures(1) Minimum: 25 psig / 1.7 bar Maximum: 200 psig / 13.8 bar...

depad pilot valve Depad main valve vent actuator inlet filter Figure 2. Type ACE97 Pad-Depad Valve Parts Single Array Manifold (SAM): Provides sense line connection and main valve connection through a single tank nozzle. Purge Meters: Prevents corrosive tank vapors from damaging upstream equipment. Principle of Operation Pad (Figure 3) NPS 1 and 2 / DN 25 and 50 Pad Valves (Figure 3) When tank pressure decreases below the pad setpoint (due to pump out operations or thermal cooling), the actuator diaphragm moves downward pushing open the pad pilot. This creates flow from the pad loading chamber...

Bulletin 74.3:ACE97 loading pressure exhausted back to tank on/off diagnostic gauge depad pilot adjustable deadband poppet cage controlled pressure range spring depad main valve o-ring seat inlet inlet bleed rolling diaphragm sensing connection open pilot diagnostic port main valve spring INLET PRESSURE ATMOSPHERIC PRESSURE TANK PRESSURE PILOT LOADING PRESSURE VENT HEADER PRESSURE tank connection INLET BLEED PRESSURE Figure 3. Type ACE97 Pad On / Depad Off loading pressure exhausted back to tank depad pilot controlled pressure range spring depad main valve o-ring seat on/off diagnostic gauge...

Bulletin 74.3:ACE97 Table 1. Control Pressure Ranges Controlled Pressure RANGEs Pad Setpoint Depad Setpoint (Above Pad) SPRING FREE LENGTH SPRING WIRE DIAMETER 1. Two nested springs are used. System Sizing Tank Blanketing systems must be properly sized to have capacity to supply enough blanketing gas to maintain the setpoint pressure, yet large enough to vent excess gas without having tank vapor space pressure rise above allowable limits. Pad valves must not be so large that they cause overpressure. Sizing must also take into account applicable codes and standards as they apply to the installation....

Bulletin 74.3:ACE97 Table 2. Flow Rate Conversion multiply maximum pump rate U.S. GPM U.S. GPH m3/hr Barrels/hr Barrels/day to obtaiN: SCFH SCFH Nm3/h SCFH SCFH Table 3. Correction Factors (For Converting Nitrogen Flow Rates to Other Gas Flow Rates) SPECIFIC GRAVITY 0.60 1.00 1.52 Correction Factor = Table 4. Correction Factors (For Converting Air Flow Rates to Other Gas Flow Rates) Table 5. Flow Rate Requirements for Liquid Pump-In Pump-Out per API 2000 Pump-Out (Inbreathing) Pump-In (Outbreathing) Flashpoint > 100°F / 38°C or Normal Boiling Point > 300°F / 149°C 5.6 SCFH / 0.15 Nm3/h of air...

Table 8. NPS 1 / DN 25 Pad Valve Capacities of 0.97 Specific Gravity Nitrogen INLET PRESSURE

Bulletin 74.3:ACE97 Table 10. NPS 1 / DN 25 Depad Valve Capacities of 1.0 Specific Gravity Air flow capacity in scfh / Nm3/h of 1.0 specific gravity air 1.0 psig 1.1 psig 1.2 psig 1.3 psig 1.4 psig 1.5 psig 1.6 psig 1.7 psig 1.8 psig 1.9 psig 2.0 psig 2.1 psig 2.2 psig 2.3 psig 2.4 psig 2.5 psig 2.6 psig 2.7 psig 2.8 psig 1. Always use the differential pressure between tank pressure (depad setpoint) and vent header (vapor recovery) pressure to calculate flow through the depad valve.

Bulletin 74.3:ACE97 Table 11. NPS 2 / DN 50 Depad Valve Capacities of 1.0 Specific Gravity Air flow capacity in scfh / Nm3/h of 1.0 specific gravity air 1.0 psig 1.1 psig 1.2 psig 1.3 psig 1.4 psig 1.5 psig 1.6 psig 1.7 psig 1.8 psig 1.9 psig 2.0 psig 2.1 psig 2.2 psig 2.3 psig 2.4 psig 2.5 psig 2.6 psig 2.7 psig 2.8 psig 1. Always use the differential pressure between tank pressure (depad setpoint) and vent header (vapor recovery) pressure to calculate flow through the depad valve.

Bulletin 74.3:ACE97 Table 12. NPS 3 / DN 80 Depad Valve Capacities of 1.0 Specific Gravity Air flow capacity in scfh / Nm3/h of 1.0 specific gravity air 1.0 psig 1.1 psig 1.2 psig 1.3 psig 1.4 psig 1.5 psig 1.6 psig 1.7 psig 1.8 psig 1.9 psig 2.0 psig 2.1 psig 2.2 psig 2.3 psig 2.4 psig 2.5 psig 2.6 psig 2.7 psig 2.8 psig 1. Always use the differential pressure between tank pressure (depad setpoint) and vent header (vapor recovery) pressure to calculate flow through the depad valve.

Bulletin 74.3:ACE97 Table 13. NPS 4 / DN 100 Depad Valve Capacities of 1.0 Specific Gravity Air flow capacity in scfh / Nm3/h of 1.0 specific gravity air 1.0 psig 1.1 psig 1.2 psig 1.3 psig 1.4 psig 1.5 psig 1.6 psig 1.7 psig 1.8 psig 1.9 psig 2.0 psig 2.1 psig 2.2 psig 2.3 psig 2.4 psig 2.5 psig 2.6 psig 2.7 psig 2.8 psig 1. Always use the differential pressure between tank pressure (depad setpoint) and vent header (vapor recovery) pressure to calculate flow through the depad valve.

1/2 NPT SENSING CONNECTION NPS 1 / DN 25, CL150 RF VAPOR RECOVERY CONNECTION 12.3 / 312 VAPOR RECOVERY CONNECTION 1/2 NPT SENSING CONNECTION TANK CONNECTION Figure 5. Type ACE97 Pad/Depad Valve Dimensions Table 14. Type ACE97 Pad/Depad Valve Dimensions DIMENSIONS IN INCH / mm FOR NPS 1 x 1 x 1 OR 2 / DN 25 x 25 x 25 OR 50 BODy WITH OPTIONS A DIMENSIONS IN INCH / mm FOR NPS 1 x 3 x 3 or 4 / DN 25 x 80 x 80 OR 100 BODy WITH OPTIONS A

VAPOR RECOVERY CONNECTION 1/2 NPT SENSING CONNECTION C NPS 1 or 2 / DN 25 or 50, CL150 RF VAPOR RECOVERY CONNECTION TANK CONNECTION NPS 1/2 x 1 x 2 / DN 15 x 25 x 50 WITH SINGLE ARRAY MANIFOLD Figure 5. Type ACE97 Pad/Depad Valve Dimensions (continued) Table 14. Type ACE97 Pad/Depad Valve Dimensions (continued) DIMENSIONS IN INCH / mm FOR NPS 1/2 x 1 x 1 OR 2 / DN 15 x 25 x 25 OR 50 BODy WITH OPTIONS A DIMENSIONS IN INCH / mm FOR NPS 1/2 x 1 x 2 / DN 15 x 25 x 50 BODY WITH SINGLE ARRAY MANIFOLD A