Industrial Valves

Karan Sotoodeh, PhD, is an Iranian author and consulting engineer, previously employed by Baker Hughes as a senior valve and actuator engineer in the subsea oil and gas industry. He has nearly two decades of experience in this industry, and has published extensively on valves, piping, actuators, and related subjects. He has lectured on valves and piping in North America, Europe, and Asia.

• 1 Flow Capacity 11.1 Introduction 11.2 Flow Coefficient Chart and Flow Curve 81.3 Rangeability and Turndown 121.4 Valve Authority 141.5 Valve Gain 15Questions and Answers 16Further Reading 202 Valve Sizing 222.1 Introduction 222.2 Isolation Valve Sizing 222.3 Nonreturn (Check) Valve Sizing 262.4 Control Valve Sizing 342.4.1 Control Valve Sizing for Liquids 342.4.1.1 Specify the Variables Required to Size the Valve 352.4.1.2 Determine the Equation Constant (N) 372.4.1.3 Determine Piping Geometry Factor (FP) 372.4.1.4 Determine the Maximum Flow Rate (qmax) and Maximum Pressure Drop (ΔPmax) 392.4.1.5 Solve for Flow Coefficient 442.4.1.6 Select the Correct Valve Size 442.4.2 Control Valve Sizing for Gas and Steam 472.4.2.1 Specify the Variables Required to Size the Valve 472.4.2.2 Determine the Equation Constant (N) 482.4.2.3 Determine Piping Geometry Factor (FP) 482.4.2.4 Determine the Expansion Factor (Y) 482.4.2.5 Solve for the Required Flow Coefficient (Cv) 502.5 Safety Relief Valve Sizing 562.5.1 Sizing for Gas or Vapor Relief 592.5.1.1 Critical Flow 592.5.1.2 Subcritical Flow 732.5.2 Sizing for Steam Relief 752.5.3 Sizing for Liquid Relief 792.5.3.1 Sizing for Liquid Relief with Capacity Certification 792.5.3.2 Sizing for Liquid Relief Without Capacity Certification 842.5.4 Sizing for Two-Phase Liquid/Vapor Relief 852.5.4.1 Sizing for Saturated Liquid and Saturated Vapor, Liquid Flashes 882.5.4.2 Sizing for Subcooled at the Pressure Relief Valve Inlet 912.5.5 Sizing for Fire Case and Hydraulic Expansion 932.5.5.1 Hydraulic Expansion (Thermal Expansion) 952.5.5.2 Sizing Safety Valve for the Fire Case 96Questions and Answers 103Further Reading 1103 Cavitation and Flashing 1123.1 Introduction 1123.2 Cavitation 1123.2.1 What is Cavitation? 1123.2.2 Cavitation Essential Parameters 1133.2.3 Cavitation Analysis 1153.3 Flashing 116Questions and Answers 118Further Reading 1234 Wall Thickness 1254.1 Introduction 1254.2 ASME B16.34 Minimum Wall Thickness Calculation 1254.2.1 Conservation Approach (Mandatory Appendix A) 1254.2.2 Nonconservation Method 1294.2.3 ASME Sec. VIII Div. 02 Wall Thickness Calculation 1344.3 Wafer Design Thickness Validation 136Questions and Answers 142Further Reading 1475 Material and Corrosion 1495.1 Introduction 1495.2 Carbon Dioxide Corrosion 1505.2.1 Corrosion Mechanism 1505.2.2 Corrosion Mitigation 1515.2.3 Corrosion Rate Calculation 1525.2.3.1 Basic CO2 Corrosion Rate 1525.2.3.2 Corrective CO2 Corrosion Rate 1545.2.3.3 Final CO2 Corrosion Rate 1615.3 Pitting Corrosion 1625.4 Carbon Equivalent 1655.5 Hydrogen-Induced Stress Cracking (HISC) Corrosion 1675.5.1 HISC and Vulnerable Materials 1685.5.2 HISC and Stress 1685.5.3 HISC and Cathodic Protection 1685.5.4 HISC and DNV Standard 169Questions and Answers 177Further Reading 1846 Noise 1856.1 Introduction to Sound 1856.2 Introduction to Noise 1866.3 Noise in Industrial Valves 1896.3.1 Mechanical Noise and Vibration 1906.3.2 Fluid Noise 1906.3.2.1 Aerodynamic Noise 1916.3.2.2 Hydrodynamic Noise 1916.3.3 Noise Control Strategies 1916.4 Noise Calculations for Pipes and Valves 1926.4.1 Acoustic Fatigue Analysis 1926.4.1.1 Sound Power Level Calculations 1936.4.1.2 Mach Number 1986.4.2 Noise in Control Valves 2036.4.2.1 Aerodynamic Noise in Control Valves 2036.4.2.2 Hydrodynamic Noise in Control Valves 2086.4.3 Noise in Pressure Safety or Relief Valves 2156.4.3.1 Calculation of Noise Emission According to ISO 4126-9 2166.4.3.2 Calculation of Noise Emission According to API 521 2186.4.3.3 Calculation of Noise Emission According to VDI 2713 221Questions and Answers 222Further Reading 2317 Water Hammering 2337.1 Introduction 2337.2 Water Hammering and Pressure Loss in Check Valves 2337.3 Water Hammering Calculations 243Questions and Answers 249Further Reading 2568 Safety Valves 2588.1 Introduction 2588.2 Safety Valve Parts 2598.3 Safety Valve Design and Operation 2598.3.1 Design and Operation Parameters 2598.3.1.1 Overpressure Criteria 2778.3.2 Principle of Operation 2788.3.3 Safety Valve Reaction Forces 2828.3.4 Safety Valve Capacity Conversion 294Questions and Answers 296Further Reading 3029 Safety and Reliability 3049.1 Introduction 3049.2 Safety Standards 3059.3 Risk Analysis 3089.4 Basic Safety and Reliability Concepts 3129.4.1 System Incidents and Failures 3129.4.1.1 Failure Rate 3139.4.1.2 Repair Rate 3179.4.1.3 Mean Time to Failure (MTTF) 3179.4.1.4 Mean Time Between Failure (MTBF) 3189.4.1.5 Mean Time to Repair and Recovery (MTTR) 3199.4.1.6 Mean Time to Detection (MTTD) 3199.4.2 Reliability and Unreliability 3199.4.3 Availability and Unavailability 3319.5 Safety Integrity Level (SIL) Calculations 3369.5.1 SIL 3369.5.2 Probability of Failure on Demand (PFD) 3389.5.3 Mean Downtime 3399.5.4 Diagnostic Coverage 3429.5.5 Safe Failure Fraction (SFF) 3429.6 Condition Monitoring (ValveWatch) 347Questions and Answers 348Further Reading 35410 Valve Operation 35710.1 Introduction 35710.2 Valve Torque 35810.3 Stem Design 36310.3.1 MAST Calculations 36310.3.2 Buckling Prevention 36910.3.3 Torsional Deflection Prevention 37410.3.4 MAST Limitation for Quarter-Turn Cryogenic Valves 376Questions and Answers 378Further Reading 38411 Miscellaneous 38511.1 Introduction 38511.2 Joint Efficiency 38611.2.1 Weld Joint Efficiency 38611.2.2 Bolted Joint Efficiency 38811.2.2.1 Bolted Bonnet or Cover Joints 38811.2.2.2 Bolted Body Joints 39211.2.3 Threaded Joint Efficiency 39411.2.3.1 Threaded Bonnet or Cover Joints 39411.2.3.2 Threaded Body Joints 39511.3 Stem Sealing 395Questions and Answers 399Further Reading 405Index 407