None-pressure-bearing Cementing Technology of Foam Cement Slurry in Loss-prone Well,Longfengshan Gas Field
There are various problems in the cementing process in Sinopec Longfengshan area,such as high well temperature,low formation pressure bearing capacity,resulting in long cementing time,high cost and uncontrolla-ble cementing quality.To solve these problems,the design idea of non-pressure-bearing cementing with foam ce-ment slurry was proposed based on the analysis of the existing cementing technology in this are,the non-pressure-bearing foam cementing technology for Longfengshan area formed,and the calculation method and cementing technology for the density and constant density gas injection cementing of foam cement slurry in the well estab-lished.Key additives for foam cement slurry such as foaming agent,fluid loss agent and early strength agent have been selected,and a new low-density foam cement slurry system developed,with temperature resistance of more than 120 ℃,foam half-life more than 420 s,water loss of 32 mL for 30 min and strength of 13.3 MPa for 48 h.All performance can meet the requirements of high temperature and deep well cementing in Sinopec Longfengshan Gas Field.The foam cement slurry cementing technology suitable for Longfengshan gas field has been formed.The application of 11 wells on site shows that this technology can effectively improve the quality of cementing.Pressure-bearing operation,multi stage cementing or tail pipe cementing operations are all replaced.This foam ce-menting technology have saved an average of more than 7 days of pressure-bearing operation and achieved signifi-cant economic benefits.The foam cement slurry cementing technology in Longfengshan Gas Field is of great sig-nificance for solving the problems of cementing leakage and pressure-bearing plugging in deep and high-tempera-ture wells in other operation areas of Sinopec,and has sustainable promotion value in other areas.
万方数据
维普
