Abrasive tools are those used in industry to grind, sharpen and polish, of which the most common varieties are grinding wheels, grinding blocks and sandpaper. They are made by mixing a binder and hard materials such as silicon carbide or corundum and forming it into a tool. They can be split into three categories, abrasive tools with inorganic (ceramic) bonding, organically bonded and metal bonded. Abrasives tools with a ceramic binder are most common as they grind well and accurately, keep their shape, do not get blocked easily or damaged by high temperature, are easy to fit and have excellent resistance to chemical attack. They can also be used with various cooling and grinding systems, which make them very popular.
The manufacturing process for making ceramic-bonded abrasive tools is very straightforward. Evenly mix the abrasives, binder, colour and any other additives, then press into various different shapes using a feldspar-clay binder. After drying, they are fired in the kiln to 1250 -1320oC. They can be fired in tunnel kilns, shuttle kilns, bell kilns and sometimes roller kilns, with down-draught kilns having almost become obsolete. The firing schedule for such products depends on the size of the abrasive tools being fired, and can be anything from 45 to 140 hours. They are usually fired in an oxidizing atmosphere, usually using a clean fuel such as natural gas or coal-gas.
Kiln furniture used in the abrasive tools industry needs to be able to carry heavy loads at high temperature for long periods of time, and therefore need good bending resistance. In the past in China, cordierite-mullite was seldom used in such applications as the hot bend strength was not sufficient. However, the advantage of using such kiln furniture is its competitive price, long service life and the fact that it doesn’t contaminate the abrasive tools. Beijing Trend’s RON, RAC, TUA and DOA materials have a high hot-bending strength and good thermal shock resistance which can satisfy the special requirements of this industry, and they have already been used in many factories at home and abroad.
|Kiln Furniture System||Main Kiln Furniture||Materials|
|Tunnel Kiln||Plain Batts Extruded Batts Plain Supports|
|Shuttle Kiln||Plain Batts Extruded Batts Plain Supports|
|Bell Kiln||Plain Batts Extruded Batts Plain Supports|
|Pushed Slab Kiln||Plain Batts|
|Roller Kiln||Plain Batts|