Salt Bed Cementing Technology Research In East Tower Old Town Block

The average depth in East Tower Old Town Block main target was more than 5000 m. Because of the depth,the long cementing section and complex condition in the column ancient salt layer,the cementing job was always difficult. Therefore, in order to meet the cementing requirements in the east tower block, the new cementing slurry system and supporting technology research to improve the quality of cementing was really necessary to be done.According to the characteristics of the Old Town East Tower salt layer, it is necessary to build cementing slurry system which should have the following properties: a higher density and a smaller water losses, too much water losses can cause fluid loss salt layer expands; the article author build three new kinds of cementing additive agents, fluid loss agent DHTF-3, retarder DHTR400 and suspension stabilizers DHTS-1,all of them can work well in high temperature. As a high temperature resistance to salt water cementing system, a lot of indoor experiments were done to evaluate dehydration properties, thickening properties, slurry rheological compatibility, compressive strength and construction performance sensitivity angle. According to indoor test results of Anti-brine slurry system and the geology of salt layer; there were several cementing difficulties including cementing long construction time, one-time job requirement, low displacement efficiency issues in 5” liner, New proposed technical was necessary to be done.Get through the cement slurry additives research, a new anti-salty formula which can resist 200℃ temperature was as follows: Dalian G + quartz + silicon micro + expander + high temperature retarder DHTR400 + high temperature fluid loss DHTF-3+ suspension stabilizers DHTS-1 + dispersing agent SXY + Coagulator ST-1 + Defoamer DQX-2. Several practical experiments were done with new cementing technology in Old Town East Tower area,The results show that new cementing slurry system and the supporting cementing technology can make the cementing quality in Old Town of tower east area very well.