Cementing cement additives include

l. Fluid loss agent

The materials that can reduce the filtration of cement slurry are collectively referred to as cement slurry fluid loss additives. At present, the commonly used fluid loss additives include polyacrylamide, Carboxymethyl cellulose organic acid compounds.

2. Drag reducing agents (diluents, dispersants, water reducing agents, turbulence induced regulators)

Satisfactory results can often be achieved by using turbulent pumping of cement slurry, drag reducing agents can control the fluidity of cement slurry, causing turbulent flow at low pump displacement. Sulfomethyl tannin, tannin alkali solution, sulfomethyl lignite all have good drag reduction effects within a certain dosage range.

3 Thickening time regulator

Due to different depths of cementing wells, it is required that the cement slurry has an appropriate thickening time to meet the needs of the operation. Thickening time regulators include coagulants retarders. Accelerator is an additive that can quickly solidify cement, commonly used include calcium chloride, sodium chloride, ammonium chloride, etc; Retarders are additives that can prolong the setting thickening time of cement slurry. The commonly used retarders are lignosulfonate its derivatives, hydroxycarboxylic acid salts (such as citric acid Tartaric acid) its derivatives.

4 Specific gravity regulator

According to different formation pressure conditions, cement slurries of different densities are required. Additives that can change the density of cement slurries are called gravity regulators, including reducing agents weighting agents.

Reducing agents include bentonite (also known as soil removal), hard asphalt, etc; Weighting agents include Baryte, Hematite, sand, salt, etc.