Portland Cement (PC)

Introducing Crown Portland Cement

As per specification of BDS EN 197-1:2003, CEM-1, 52.5 N Crown Portland Cement is an Ordinary Cement prepared by mixing clinker 95-100% and gypsum 0-5%. This cement is also called Ordinary Portland Cement (OPC). Portland Cement is the Cement obtained by initimately mixing together calcarious and argillaceous materials, burning them at clinkering temperature upto about 1450 degree celcious and grinding the resulting clinker (calcined product ) at required fineness and finally mixed with gypsum to obtain cement. This cement is a finely ground mixture of calcium aluminates and silicates capable of setting and hardening by chemical reaction with water. It is a binding material, which is used in engineering constructions.

Technical Specifications:

CEM-I, 52.5 N

Composition: Clinker 95-100%, Gypsum 0-5%

Benefits of Crown PC:

  • Can gain high early strength
  • Ensures durability
  • Resists cracking
  • Makes construction faster
  • Effective in producing high strength concrete
  • Used in construction of tall buildings or high-rise buildings & housing developments, Industrial buildings, factory buildings, and all type of construction works
  • Exclusively used in bridge, culvert, flyover, runway, pre-stressed concrete, pre-stressed prefabricated applications, tunnel mold systems & in the construction of mass housing
  • Frequently used in reinforced concrete elements & other prefabricated productions, particularly for pretension prefabricated applications
  • Mostly used in concrete classes of high compressive strength required applications

Physical Properties:

Crown Cement is tested for fineness by Blaine’s air permeability method. The specific surface of cement is 300-380 m2/kg.

Crown Cement is tested for soundness by the Le-Chatelier method and autoclave test. The unareated cement shall have an expansion of less than 2.00 mm (Le-Chatelier method) & 0.08% (Autoclave Method) respectively.

Setting Time:
The setting time of cement is tested by Vicat apparatus method.
Initial setting time is not less than 45 minutes.
Final setting time is not more than 375 minutes.

Compressive Strength:
The compressive strength of Crown Cement is tested in compression machine.
In 2 days it is ≥ 20 MPa
In 28 days it is ≥ 52.5 MPa

Chemical Properties:
Ratio of percentage of lime to percentages of silica, alumina and iron oxide when calculated the LSF becomes 0.90-0.94.
Insoluble residue (by mass) 0.75% max.
Total Chloride Content 0.10% max.