ConTec NC-505


ConTec NC-505 is a non-corroding, chloride free accelerator. It does not corrode reinforcing steel or pre-stressed strands in concrete. It promotes strength development of the concrete and meets ASTM C 494 requirements as a type C admixture. NC-505 offsets the effects of cold weather by increasing hydration speed.


ConTec NC-505 is compatible in concrete with all commercial air entraining admixtures. The amount used will depend upon the setting time of the non-admixture concrete and the temperature at placement. It may be added to the mix on the sand or in the water.


ConTec AC-505 is available in 55 gallon (208 L) drums weighing 620 lbs (281 kg) and 275 gallon (1041 L) totes weighing 3150 lbs (1429 kg).


Specific Gravity at 77F……..…… ….. 1.30 – 1.32
Viscosity at 77F, cps ……….…..… .…. 50—100
Weight per gallon ………………. ….….. 10.90
% Volatile matter (NVM(1)) …………. …… NA


● Compatible with all types of Portland cement.
● Offers a significant reduction in corrosion to steel reinforcing.
● Increases the early strength of a concrete mixture.
● Designed for use in cold weather concreting.
● Shortens setting time for concrete.
● Easily dispensed with conventional admix dispensers.


ConTec NC-505 will freeze at approximately -15°C, but can be completely restored by thawing and thorough agitation. It may cause irritation to eyes and skin upon contact. Proper protection should be worn.


The dosage range is 0.5 – 2.6 liters per 100Kg of cement. NC-505 at 0.78 – 0.98 liter per 100Kg of cement will reduce the setting time of typical Type I cement concrete by 2-3 hours (at 10°C) and a 25 to 50% increase in 3 day compressive strength is normally achieved.