Sand Production Prediction And Proper Sand Control Technology Research In Ld Oilfield

For 80 percents of the formation in BOHAI oilfield is loosen sandstone, the sand control operations turn to frequent operations. This article forecasts the sand flow situation by the drilling core test with B factor method and Schlumberger method and gets the conclusion that LD oil field is always appeared sand flow, also verified on job site. This article also forecasts the interface pressure difference of sand flow and gives instructions to the managements of wells production. For irove the production of oilfield maximally and low operation cost, this article researches and analyzes the moderate sand control well-coletion technology. The moderate sand control method is always described as followed: Put the special screen pipes into oil layer and moderately enlarge sand control size, and allow the layer sand under regulated size into well holes, send the sand particles to ground by the artificial lift way and then separate them. By getting the fine sand out of the layer near screen pipes, the layer is"unloaded"to cause the layer swelled and cut to damage the bad zone developed in the well-coletion operation, so the"earthworm hole"appears near the screen pipes and gets the oil pass-way dredged to irove the penetration rate of the well layer. The main step as followed: In the level branch holes and level holes and regular directional holes, not put the casing into holes, not well cementation, directly put the special screen pipes into holes to realize sand control, or carry out the perforation operation for production casing, and then put the special screen pipes into holes to realize sand control. This article deeply analyzes the main factors to affect moderate sand control success: the accuracy of sand control, optimized screen pipes, the relation between production pressure difference and sand flow, the relation between water flow rate and sand flow etc. For the accuracy of sand control we change the control size from 4~6 d50 to 6~8 d50 and get better production. As one of key techinics of the moderate sand control well-completion technology, this article introduces the application of the main self-contained technique"low frequency and variable frequency starting". By the instruction of mentioned above, we applied the moderate sand control well-completion technology in SZ CF1 and got good performace. After that we have applied this technology in LD oilfield. The onsite good performance proves that the moderate sand control well-completion technology is worth to expanding in BOHAI Bay oilfield.