What are Accelerators?

Accelerators are chemical additives used in cementing and construction applications to speed up the setting and hardening process of cementitious systems. These additives enhance early strength development, reduce waiting-on-cement (WOC) time, and improve operational efficiency—especially in low-temperature environments where cement naturally sets more slowly.

Accelerators work by modifying the hydration reaction of cement compounds, particularly tricalcium silicate (C₃S), which is responsible for early strength gain. Common chemical accelerators include calcium chloride, sodium chloride, triethanolamine, and various organic salts. Their function is to increase the rate of ion dissolution and crystal formation, which shortens the time it takes for cement to gain strength.

In oil and gas well cementing, accelerators are vital for shallow or low-temperature wells where faster setting times reduce the risk of slurry migration and allow earlier continuation of drilling operations. In construction, they help in early formwork removal, cold-weather concreting, and rapid repair jobs.

While accelerators improve job efficiency, they must be carefully selected and dosed to avoid issues like flash setting, excessive heat generation, or corrosion of steel reinforcements (especially with chlorides).

Proper handling is important as some accelerators can be corrosive or irritating to the skin and eyes. Always follow safety data guidelines when storing or applying these chemicals.

USES AND APPLICATIONS

INDUSTRIES

Accelerators are commonly used in:

• Oil and gas well cementing to reduce setting time
• Cold-weather concrete pouring
• Precast concrete production for faster demolding
• Rapid repair applications in construction
• Shotcrete and tunnel lining projects