Loading...

OIL WELL CEMENT (OWC)

OIL WELL CEMENT (OWC)

CLASS G (HSR) - API SPEC 10A

The types of cement are categorized according to the American Petroleum Institute (API) Specification10A standards, which has identified 8 classes of cement according to the depth of the well, the temperature and pressure. Cement is also classified in grades: Ordinary (O), Moderate Sulfate Resistant (MSR), and High Sulfate Resistant (HSR). Sulfate resistance is based upon the C3A (Tricalcium Aluminate) content, which has a bearing on the durability of the cement under sulfate attacks.

The product obtained by grinding Portland cement clinker, consisting essentially of hydraulic calcium silicates, usually containing one or more of the forms of calcium sulfate as an intergrouned addition. No addition other than calcium sulfate or water, or both, shall be interground or blended with clinker during manufacture of class G well cement. This product is intended for use as basic well cement.

Application:

  • Exploration for and the production of oil and gas
  • As a sealing water wells
  • In waste disposal wells

OIL WELL CEMENT (OWC)

Constituent Specifications
Chemical Composition API Standard requirement Average Values Class G-HSR
Loss on ignition ≤ 3.0 % < 2 %
Insoluble residue ≤ 0.75 % < 0,6 %
MgO ≤ 6.0 % < 2 %
SO3 ≤ 3.0 % < 3 %
Alkali content (expressed as Na2O equivalent) ≤ 0.75 % < 0,7 %
C3S 48 – 65 % > 59 %
C3A ≤ 3.0 % < 2 %
C4AF + 2C3A ≤ 24 % < 18 %
Physical Properties
Free fluid content ≤ 5.9 % < 4,5 %
Compressive Strength
Compressive Strength 8h, 38°C ≥ 2.1 MPa > 4,5 Mpa
Compressive Strength 8h, 60°C ≥ 10.3 Mpa > 14 Mpa
Thickening time 90 – 120 min > 100
Maximum consistency (15-30 min) ≤ 30 Bc < 18 Bc

Packing

  • In big bags 1.5 ton.