Application of q strength enhancer for deep well cement slurry at low temperature

There are several problems existing in Zhongyuan oilfield, e.g., reservoir is deep and sporadic; geothermal gradient and well bottom temperature are high; cementing interval is long; cement slurry does not easily consolidates at low temperature and cement stone strength develops slowly, etc.. To cope with the problems, a cemet strength enhancer named G606 was developed. The enhancer produces a little influence on cement slurry flowability, reduces filtrate loss of slurry and can short cement slurry's thickening time specially at low temperature. The property of the slurry prepared with the enhancer has short thickening time, displays the right angle curve and cement strength develops quickly at low temperature. It can fully satisfies the requirements of normal logging time and downhole jobs.The enhancer was used in 36 deep wells, and the cementing operation was successful with the cementing qualified rate of 100% and excellent rate of 89%.