斯伦贝谢负压射孔.pptVIP

射孔技术 刘 川 2004年9月 OUTLINE 射孔弹和射孔枪系列 - PowerJet 动态负压射孔技术 – PURE 定向射孔技术 - WOPT What is PURE? Schlumberger Propriety Rights Notice: The PURE system is a proprietary property of Schlumberger and is the subject of US Patent Application No.:US 2002/0020535 A1 dated February 21 2001, and PCT Application No.: WO 01/65060. The PURE system may only be used pursuant to a contract agreed with Schlumberger and must not be distributed or divulged to third parties, or duplicated in whole or in part, without prior written permission by Schlumberger. PURE Objectives Maximize well productivity or injectivity by minimizing perforation skin Eliminate the need for secondary perforation cleanup methods in low permeability gas and oil wells. Minimize cement-to-sand face micro annulus Reduced shock in the wellbore Importance to Productivity of Clean Perforations Kc/K=1 More important than increasing shot density from 6 to 12 spf with Kc/K0.1 More important than an additional 30% penetration with Kc/K0.1 With Kc/K=0.3, a 25% increase in penetration gives a PR similar to Kc/K=1 with no increase in penetration PR Versus DamagePerforation = 12 inches, SFP = 6, Kd/K = 0.2 PR Versus DamagePerforation = 12 inches, SFP = 12, Kd/K = 0.2 PR Versus PenetrationDamage = 8 inches, SFP = 6, Kd/K = 0.2 PR Versus PenetrationDamage = 12 inches, SFP = 6, Kd/K = 0.2 Current Paradigm Crushed Zone Damage Perforating under balance helps remove crushed zone damage How much under balance do we need? Depends on rock properties (permeability, strength, porosity), effective stress and tunnel diameter and maybe on rate of drawdown How much under balance do we get? Depends on wellbore geometry etc Lab Set-up for Single Shot Tests 测试术语 K = 原状地层渗透率 Kc = 射孔损伤带渗透率 CFE = 岩心流通效率 Ratio of flow through through the perforation tunnel vs flow though a drilled tunnel with the same dimensions and zero damage Best is CFE = 1 Choose The Best Perforation? Perforation Dynamics Choose The Best Perforation? Perfo