Purchasing Guide for Wellhead & Christmas Tree ... - Stream Flo

API Specification 6AAPI Specification 6A (ISO 10423) is the recognizedindustry standard for wellhead and christmas treeequipment that was formulated to provide for theavailability of safe, dimensionally and functionallyinterchangeable wellhead and christmas treeequipment. This specification includes detailedrequirements for the manufacture of tubularsuspension equipment, valves, and fittings usedat the location of oil and gas wells to contain andcontrol pressure and fluid flows.Specification 6A also serves as the referencesource for the design of flanged end and outletconnections for use at 2,000 to 20,000 psimaximum rated working pressures and a familyof gate valves for use over these same pressureranges.Since API Specification 18th Edition waswithdrawn, this booklet covers the 19th Editionwith references to the 17th Edition.Abbreviated TermsAQL Acceptable Quality Level PQR Procedure Qualification RecordCRA Corrosion Resistant Alloy PR Performance RequirementDAC Distance Amplitude Curve PSL Product Specification LevelER Equivalent Round QTC Qualification Test CouponFEA Finite Element Analysis r.m.s. Root Mean SquareHAZ Heat Affected Zone RL Repair/Remanufacture LevelHBW Brinell Hardness R mUltimate Tensile StrengthHIP Hot Isostatic Pressing ROE Radius of ExposureHRB Rockwell Hardness Scale B SSV Surface Safety ValveHRC Rockwell Hardness Scale C TC Test CouponNDE Nondestructive Examination UNS Unified Numbering SystemNPT National Pipe Thread USV Underwater Safety ValveOEC Other End Connection WPQ Welder Performance QualificationOEM Original Equipment Manufacturer WPS Welding Procedure Specification1