Factory:  Corner Steyr & Alfa Sts 
Aureus Industrial sites 
RANDFONTEIN  
Email: info@keramicalia.co.za
Website: www.keramicalia.co.za
Cell: Dave  082  808 4757
Email: keraccounts@iafrica.co.za
Accounts: Myrtle Wakeford
Tel: (011) 764 2139
Tel: (011) 412 3261
P O  Box 2288
Wilro Park,1731

It is often very convenient to perform repairs from outside of a furnace, especially when hot, and the savings in downtime can be phenomenal. There are 3 main types of installation:

* Injection against burden. This is usually the case in blast furnaces and rotary kilns. The material sets rapidly in contact with heat, and pushes back the burden, leaving a new lining of virgin refractory         between the worn lining and the charge material.
* Injection into a cavity. This is usually the case with electric furnaces and hot blast stoves, and the hearth of blast furnaces. Normally the inside of the cavity is hot and the shell is cool.
* Pumping into an exposed area. This is usually the case with furnace floors. It may also be used for new installations where access is difficult.

There are four varieties of flow characteristics:

1. Super fluid: Materials with remarkable penetration. Good for stopping gas tracking.
2. Thixotropic: Used when limited penetration is desired.
3. Self levelling: Preferred for pumping into exposed areas.
4. Cohesive: Preferred for injection against burden, because penetration into the burden matrix is minimal.

The full chemical range of refractories can be made:
Alumina for abrasion resistance.

* Fused chrome alumina for extreme slag resistance.
* Zirconia for extreme density where the burden lifting capacity is at a premium.
* Basic.
* Carbon/SiC where high thermal conductivity is desired, eg. against water cooled panels.
* Aluminosilicate for insulation. Keramicalia has a wide range of injectable materials, but nearly every new application has required a tailor made material.

The client should consider his requirements with regard to the following:

* What kind of pump is available? Putzmeister, squeeze, diaphragm or worm.
* What is the working temperature and at what temperature will the installation be done?
* Should the material be insulating or conductive?
* Is electrical insulation required?
* What distance and height will the pump be relative to the installation?
* Will the material be in contact with carbon or magnesia refractories? (A water free material may be required).
* Where will the material penetrate to once the cavity is filled?
* What is the expected volume of the cavity?
* What abrasion will the material be exposed to?

It is often worth considering how the success of the installation can be measured, before the job is started. To evaluate the economic feasibility of the installation, downtime saving is usually the first consideration. Downtime with pumping can be less than an hour on a rotary kiln, and can save up to two weeks downtime. The next most important consideration is campaign extension. This can save millions of rands in a blast furnace. Injection is likely to cost less than 10% of costs it will save in terms of lost production and campaign extension alone.