The well condition differs in thousands of ways in the oil-gas well cementing. the lowest temperature is lower than the eternal frost formation of freezing point, and the highest can reach 350 heat production well and geothermal well. And some wells’ pressure is close to the atmospheric pressure such as shallow Wells, and some wells’ is as high as 200 MPa. Except the temperature and pressure, soft porous strata formation, corrosive liquid and high pressure formation fluid are also have ask to the cement. And in the cementing construction site may not be equipped with a variety of cement. And in general, only one or two API standard cement, so additives is needed to adjust the cement properties to satisfy the cementing requirements.
Commonly used oil well cement addtives can be divided into the following general categories
- Fluid loss additive
- Washing liquid
Except the oil well cement additives, there are many other admixtures which can satisfied the cementing requirements.