Building Materials, Third Edition

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… Water impermeable expanding cement is used for repairing concrete and reinforced
concrete constructions, for water-proofing tunnels and pit shafts, in underground and
underwater constructions, for water-impermeable joints.

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—2g is a quick-hardening hydraulic binding material
obtained by combined fine grinding or mixing of high-alumina slag and natural dihydrate
gypsum (30%). Setting of gypsum-alumina cement begins not earlier than in 20 min and ends
not later than in 4 hours after mixing with water. Specimens from gypsum-aluminous cement
paste should be, after one day, impermeable to water applied at a pressure of 10 atm. Linear
expansion of cement after one day of hardening should not be less than 0.15% and not more
than 1.0%, its average value after 28 days being 0.1 to 0.3%.

… Gypsum-aluminous cement is used for the manufacture of non-shrinking and expanding
water-impermeable mortars and concretes, for caulking joints, for waterproofing underground
mines.

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The oil well cement is used for the purpose of securing oil-well pipe casing with the surrounding
earth and rocks. It is manufactured by grinding clinker consisting essentially of hydraulic
calcium silicates. No material other than calcium sulphate be interground or blended during
manufacture of cement. However, set modifying agents such as lentonite, barite and fly ash
may be added in classes D, E and F types of oil well cement. The oil-well cement are classified
as A, B, C, D, E, F, G, H and J-class depending upon its use at particular depth from ground
level and the ground condition.

(a) Class A — intended for use from surface to 1830 m depth, when special properties are not

required.

(b) Class B — intended for use from surface to 1830 m depth, when conditions require

moderate to high sulphate resistant type of the cement.

(c) Class C— intended for use from surface to 1830 m depth, when conditions require

ordinary to high sulphate resistant type of the cement and high early strength.

(d) Class D — intended for use from 1830 to 3050 m depth, when conditions require moderate

to high sulphate resistant type of the cement under moderately high temperatures and

pressures.

(e) Class E — intended for use from 3050 to 4270 m depth, when conditions require moderate

to high sulphate resistant type of the cement under high temperatures and pressures.

(f) Class F — intended for use from 3050 to 4880 m depth, when conditions require moderate

to high sulphate resistant type of the cement under extremely high temperatures and

pressures.

(g) Class G — intended for use as a basic cement from surface to 2440 m, when conditions

require moderate to high sulphate resistant type of the cement and can be used with

accelerators and retarders to cover a wide range of well depths and temperatures. No

additions other than calcium sulphate or water or both, shall be interground or blended

with the clinker during manufacture.