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3 Books you should not miss if you are from AAC Blocks Industry

  3 Books you should not miss if you are from AAC Blocks Industry 1.       AAC Blocks for Superior Masonry Construction Description: This book will introduce you to the world of Autoclaved Aerated Concrete blocks. The AAC blocks have taken the construction industry by storm within the last decade. But there are variety of questions within the mind of users. This book is an attempt to answer them. It will teach you step-by- step how to construct a masonry wall with these wonderful blocks. The bonus section of the book will assist you learn the provisions of IS code 2185 in only 8 minutes! The book also will discuss exact cost savings achieved by the AAC blocks. About the Author: Mukund Joshi He is a concrete technologist by profession and an orator — having lectured in additional than 10 countries within the field of concrete technology. He has worked on numerous international projects designing a concrete mix. He has consulted on numerous AAC plants on  er

Chemical Composition of AAC

  Chemical Components in AAC Blocks If we test AAC Blocks with Spectro Photometer, chemical composition can be found out.  One of the same report is given below.

What is AAC? What are the properties of AAC? How AAC blocks are produced?

  Definition of AAC Blocks   AAC Blocks   A - Autoclaved A - Aerated C - Concrete   Autoclaved aerated concrete is a lightweight concrete containing uniformly distributed voids that is subjected to high-pressure steam curing.   Production of AAC Blocks   This is a light- weight building material produced by autoclaving a set mix of fine siliceous materials such as ground silica sand or flyash and the binders like Portland cement and lime. Lightness is achieved by incorporating a large proportion of closed microscopic pores in the slurry with the help of entraining or foaming agent. The basic raw materials are fine-ground sand or fly ash, cement, quicklime, anhydrite or gypsum, water, and aluminum  powder or paste as a rising component. A suitable mixture of these raw materials is poured into a mould, and the rising process starts due to the development of hydrogen gas formed by the reaction of aluminium in the alkaline suspension. After 20 to 40 minutes the maximum rising

What is Aluminium Powder? Why it is used in AAC Plants?

  Aluminium Metal powder or paste Aluminium powder, which is commonly used as a reaction agent in AAC Plants, is a fine granular powder made up of Aluminium Metal. Process of Manufacture: The aluminium powder is usually manufactured in many forms such as flaky particles, granulated powder (atomised aluminium) etc. There are different processes one can use for the production of aluminium powder. The metal is melted in furnaces, and the temperature is maintained around 720 to 760 C. Atomised Aluminium is produced by blasting the stream of molten Aluminium into small articles by air jet. For this purpose, an atomiser is employed which consists of a straight tube with lower end dipped in molten metal and upper end terminating as a little orifice. A jet of hot air under pressure is passed through armular opening near the top which impinges on a stream of molten Aluminium drawn by suction through the orifice. This results in the formation of small particles of Aluminium. Th

Why the vacuum should be done for AAC Blocks?

  Purpose of Evacuation: Before steam is often entered into the autoclave, the  autoclave must be evacuated by reducing the  pressure within the autoclave with the utilization of  vacuum from the air pump or steam ejector.  Hereby the existent atmosphere within the autoclave  is removed. By keeping the evacuation pressure below the  saturation pressure of water, which is out there within  the green cakes, steam is released from the green  cakes as a desired side effect. Air and hydrogen which are still present within the  green cakes are scavenged from the autoclave by this  self-formed saturated steam. Why the vacuum should be done  for AAC Blocks? The vacuum is mandatory. This will remove the entrapped air from autoclaves. Otherwise, liquid steam marks are going to be visible  after autoclaving. Those blocks are sensitive and have a tendency to  break easily. If it's not broken, please keep the  separate stacking/drying for a couple of days. If there's no vacuum, do the purgi

AAC vs Non AAC Blocks

  Why Autoclaving is required when Non Autoclaved Aerated Concrete Blocks are available in the Market? The matrix and the firmness of the AAC products are made due to autoclaving.  AAC vs Non AAC Blocks Technically, such product will start cracking by itself  when it approaches equilibrium moisture content  after a couple of years. In the case of ordinary concrete products, there are  no shrinkage troubles during the drying operation. But in foamed or aerated concrete the mixture is air  and if manufactured without autoclaving, drying  shrinkage will cause cracking. The calcium silicate hydrates formed during  autoclaving is more stable than the one formed of  cement at room temperature. Autoclaved products have low shrinkage. Cement will need four weeks to achieve its final  strength at room temperature whereas, autoclaving  takes only 12 hours. to get desired strength. The mechanical strength will not be very high and  through the drying, the shrinkage is going to be  excessive. It i

Reactions during Autoclaving of AAC Blocks

Reactions during Autoclaving of AAC Blocks In the first phase, a topochemical reaction takes place during which the lime and silica acid are the reactants.  Water doesn't happen within the actual rejection; it’s only built into the new formulations that are formed.  These reactions occur within the border areas of the raw materials, starting at the active spots (e.g. on the edges) of a crystal. The second phase of the reaction will mainly involve the solvent phase where the lime and silica acid, both of them are dissolved in water, will react into insoluble calcium silicate hydrates.  These hydrates will form a structure. Looking at this in a little more detail from when the  green blocks enter the autoclave, the main reactions  that occur are broadly as follows: Over 2 hours or so, as the pressure and temperature increase, the normal cement hydration products that formed in the green state progressively disappears and the pulverized fly ash becomes reactive.  C-S-H(I) forms, partl

AUTOCLAVING - NUTS AND BOLTS OF AAC BLOCKS MANUFACTURING (By Srinivas Goud Chikati)

 

One and only Book available in the world on this subject - ‘Autoclaving of AAC Blocks'

  7 ReasonsWhy this Book Must Be Read 1. India is full of fake AAC consultants. This book will save lakhs of money spending on them. 2. By understanding the process and following the checklists and log sheets, one can save lots of money. 3. This book is written by one of the five  senior  AAC professionals available in the country with more than 17 years of hands-on experience in AAC Plants. 4. When you are planning the New AAC Plant, this will enable you to choose the right Autoclaves, and the systems connected to it. 5. Most of the plans have no long vision. They hand over the plant to some contractors and ask for the production. They damage everything in 4 or 5 years. This is ok when you want to do business for 4 or 5 years. This book and my next book on Process Control will enable you to choose your own team and manage the plant for a long time. 6. Much attention was given to Safety. If the plant is safe, employees can work without any fear , and productivity will be increase