Cement is one of the most important building materials, ties up the material together. The is grey and soft which helps to make the concrete. Manufacturing of cement is by two materials, Calcareous (limestone) and Argelaceous (clay). The raw material burn in the component is known as cement. The strength of the mainly depends on the strength and colors of cement.
The procedure of manufacturing of cement:-
- Mixing of raw materials – There are two processes of mixing the raw material and it is the dry process and wet process. In the dry process, the raw material gets crush in the crushers just to get the size of 2-5cm pieces. The crush material is a grind to get the fine particles in the tube mill. The fine grinds store in the material gets store in the hopper after the screening.
- The dry process is high is cost production, costly, consumes low fuel, quite hard in raw materials. In a wet process, the raw material is crush and make powder form and is store in silos. The clay gets a wash in the washing mill to remove to stick matters found in the clay. The two mixtures pump to mix in the predetermined proportion and passed through a series of screens. In the storage tank, the cement slurry is store. The wet process if low in cost production, cheaper, high fuel consumption, any type of raw material.
- Burning of raw material – The raw material process burns, from 1500-1700C. By burning the aluminum and silicates, we get small and hard stone which is known as clinkers. The clinker size is up to 5-10mm.
- Grinding of clinkers – The clinkers get chills and it gets into the mills. The clinkers are grinds finely into the powder in a steel ball. 2-3% of gypsum gets to add in a retarding agent while grinding is known as cement.
- Storage and packaging – The grinds cement store in the silos and it is pack in 50kg bags and send to the market.
Types of cement, uses, purpose:
- Ordinary Portland cement – It commonly operates all types of construction works. Ordinary Portland is working as residential construction, the type is not in need.
- Rapid Hardening Portland Cement – This implements where the high strength is in need to be achieved in the beginning stage quickly. Rapid hardening Portland applies in road pavement works, precast concrete casting (slabs, beams, etc)
- Sulphate Resisting Cement – Sulphate Resisting is the concrete in which there is direct contact with the soil. Sulphate resisting applies in a pile foundation, in coastal area work, sewage, and water treatment plants.
- Low Heat Cement – It applies is mass construction, in high wear resistance required area. The purpose of Low heat is to work in dams, hydraulic engineering concrete, etc.
- Quick Setting Cement – It applies where the works need to be done quickly. The purpose of it is in underwater construction, rainy weather construction.
- Portland Pozzolana Cement – The high compressive strength with the age, unlike rapid hardening cement. It is cheap and affordable, water tightness.
- High Alumina Cement – High alumina is operating in construction like factories, refineries, etc. The purpose of high alumina is to employ in sewage structures and acidic structures, it is counter to high temperature.
- Coloured Cement – It requires for any aesthetic purpose like artificial marble and floor finishing.
- White ordinary Portland Cement – It makes use of whitewashing purposes for aesthetic purposes. It employs as a base coat before painting and covers the hairline cracks o the concrete surface to give a smooth finish.
- Air Entraining Cement – This fills up the gap in the concrete by which the excessive amount of water during casting. The purposes are to frost resistance concrete.
- Hydrophobic Cement – It is useful in a wet climate. Hydrophobic keeps a longer duration in wet climatic conditions.
- Expansive Cement – Expansion is to expand and increase the volume while settled because it uses to avoid shrinkage of concrete, used in repair works and also used in hydraulic structures.