Calucem Instra 40 Calcium Aluminium Cement (25kg)

Calucem Instra 40 is a normal setting, rapid hardening calcium aluminate cement (CAC) with high early strength. It differs substantially from the usual calcium silicate cements (Portland cements) in its manufacturing process, chemical composition and rapid strength gain.

Key Features

ISTRA 40 is composed of calcium aluminates with the following characteristics:

• High early strength

• Refractoriness

• High abrasion resistance

• Resistance to biogenic sulphuric acid corrosion (BSAC)

ISTRA 40 meets the requirements:

• EN 14647 for Calcium Aluminate Cements
• is controlled in accordance with EN 14647.

Shelf Life : 6 months (when stored under dry conditions)

Production :

ISTRA 40 is produced by melting selected raw materials (bauxite and limestone) in special kilns. After cooling, the clinker is ground using ball mills.

Technical Data :

The following information represents typical values for the quality control carried out in our plant.

• Chemical Composition (%):
  • SiO(2) : ≤ 6

  • Al(2)O(3) : 38–42

  • Fe(2)O(3) : 13–17

  • CaO : 36–40

  • MgO : < 1.5

  • SO(3) : < 0.4

Setting Time and Water Demand:

• The testing of the setting time is performed using the mortar in order to describe the behaviour of the ISTRA 40 in mixtures with a workable consistency. A mixture containing CEN-standard sand and using a water/cement ratio of 0.4 is produced for testing the mortar on the basis of EN 14647.
• Mortar: 
  • Initial set : 1 – 4 h
  • Final set : maximum 120 min after initial set
  • Water demand : 23 ± 2%

Development of strength

After setting, strength develops very rapidly. ISTRA 40 is a cement with very high early strength and high compressive strength. After one (1) day, the compressive strength is higher than that of high grade Portland cements CEM I 52.5 R after 28 days.

• Development of strength [N/mm2 ]

  • Comprehensive strength (6 hours) : >30

  • Comprehensive strength (1 day) : >50

Refractoriness

• After drying out, mortars and concretes made from ISTRA 40 slowly emit their hydrate water without destroying the matrix. At high temperatures (> 1000 °C), ceramic bonding occurs between the high alumina cement parts and the refractory aggregates. These ceramic bonds make ISTRA 40 an excellent binder in refractory concretes and other refractory mortars or gunning mixes.

Quality

• Like all other Calucem products, the production of ISTRA 40 is subject to stringent quality control.
• Constant monitoring of all components ensure a consistent quality.
• The production plant is certified according to EN ISO 9001 – certificate number CH08/1542 and the Environmental Management System EN ISO 14001 – certificate number CH08/1543.