This newsletter was written on 2.5. 1997! Then my photocopier broke. Colin Coomer lent me his old machine. We were both bidding on this machine at an auction, but I backed down. Anyway, thanks, Colin.
As you can see we are now on e-mail and have a web site. The web site, when it works, contains most of our data sheets. You can download it or we can give you all our data sheets on a disc.
I have had a lifelong assosciation with the medical profession. My father was a doctor, my daughter is a nurse, my wife and my mother have both been medical receptionists and my mother in law is a matron. South Africans tend to regard doctors as omniscient and infallible beings. If a doctor lets on to a patient that he does not know everything and can possibly make a mistake, he will probably never see that patient again. If he keeps up the image of being infallible, he may feel terribly guilty about it, but at least he will stay in business.
So what can you do about it? My advice is this; When you meet your doctor, tell him that you don't expect him to diagnose your ailment. I tell my doctor that I don't know what's wrong with my body even though I live in it, so I really can't expect him to find the problem. I would, however, gladly pay him to listen to my layman's description of what I feel in the hope that he may have some suggestions. You will probably see your doctor visibly relax, and I am sure he will be totally honest with you.
Another thing I believe about medicine is that half of healing is psychological. Sangomas successfully kill people just by convincing them they are going to die. Conversely, people have been seen to survive extreme injuries if they have a strong will to live. I believe my wife saved my life when I was dying from malaria and failed to respond to treatment. She stayed at my side and fuelled my will to live. She even invented stories about cute things my daughter had done. My running friend Mervyn Niland has some fascinating stories about mind power. I went to one of his seminars recently, and he got us all, everyone in the whole group, walking over red hot coals! Nobody even felt any heat on their feet or showed any sign of burning. As a refractories technologist I find that fascinating. Go on, try it, Mervyn's number is 083 286 1936.
Product Feature - KERAPUMP
Since I first joined the Ceramic Society, Dr Richard Kruger was dead keen on cenospheres. He introduced me to them, and opened up a whole new world of possibilities. After many years of toil and maneuvering, Richard realised a dream and commercially produced cenospheres. We worked together closely and Richard gave me immense support to create a whole new generation of refractories.
Cenospheres are tiny hollow ceramic spheres which impart amazing properties. They flow almost like water and impart brilliant thermal insulation properties. I call the new generation of refractories "Cellular Insulation". The materials made from cenospheres appear to be solid, but are full of microscopic sealed cavities. Many readers will have seen the demonstration or the advertisements of me holding in my bare hands a crucible with 2000øC molten steel in it.
Kerapump is a series of pourable or injectable refractories. Kerapump 1 stood around in the lab for a while. Colin Coomer asked me if I could meet the stringent spec. for an insulation material for Mossgas. I said I think I have just the right thing. I had tests done on Kerapump 1 and it exceeded the strength requirements so far that Mosgas rejected it!
Iscor Newcastle were pumping an imported insulation foam on their hot blast stoves on hot spots. They had to repeat the procedure every few months on exactly the same spots. They agreed to try Kerapump 1, and it worked permanently. Some years later Mike Kuys 'phoned me at 2am on a Monday morning. A section of the roof of the hot blast stove had fallen in, just after they had spent R20million on relining the blast furnace. If they did not get the stove going soon, the whole blast furnace would solidify and have to be rebuilt. Kerapump was the only hope. Everyone pitched in to help. We even had two ex bank managers driving bakkies up and down from Newcastle. Four days later the stove was back on line.
We didn't have a party, we all went off to sleep for a long time. Some months later Mike Kuys 'phoned again. Slight problem; somebody pumped Kerapump into the compensators, a sort of expansion bellows, and they jammed solid as a rock. Could I make something compressible?
And so Kerapump 2 was born.
Billy Wolmarans and I repaired cracks behind the buckstays at Vanderbijl's coke ovens. The cracks were totally inaccessible behind the buckstays, we we plugged up all the openings around the buckstays with Versimould Plug, leaving a pipe protruding from the gap. Into this we pumped Kerapump 1. It was most dramatic. Smoke and flames were billowing out from the roof over the regenerators, and about thirty seconds after we started pumping, the smoke and flames would suddenly vanish. Working conditions were apallingly hot. Everything got hot.
The floor was so hot that at times when we picked up plastic bags of Kerapump the bottom of the bag stayed stuck on the floor. Kerapump kept setting in the pump because the water was too hot. Back to the lab.
Kerapump 3 was invented; more fluid, with a longer setting time, or rather more of a heat set. Now it can travel far around a furnace shell, then penetrate cracks and set on its way to the hot face. Martin le Roux discovered Kerapump 3 for glass bending moulds. Previously glass benders had to make clay moulds, prefire them to ñ1100øC and then bend their glass over them. They used to break after about three bendings. Now they can make them with Kerapump 3, fire to 400øC or use them straight away. They seem to last indefinitely. This was such a revolution in Martin's business that he spread the news far and wide. He couldn't do enough for me. He gave me his whole pipe collection, including beautiful hand-carved meerschaum pipes.
I find Kerapump 3 ideal for modelling, because it takes up very fine detail, is volume stable and easily workable to a fine finish, due to its very fine homogeneous microstucture.
Kerapump 4 is still slower setting and softer. Kerapump 5 is lower density, designed to replace Marinite, an asbestos based material used in the aluminium industry. We made some superb Marinite replacement parts for a customer, but he was reluctant to change. It turned out that if he changed, four of his colleagues would be out of their full-time jobs machining Marinite! Our latest development is floats for continuous casting of aluminium. Gideon Kriel is doing the development. The floats control the flow in the same way as a needle and seat mechanism in a car's carburettor. Gideon's samples look stunning compared to the calcium silicate components which have replaced Marinite.
Kerapump 6 is a dense pumpable material with a high zirconia content which has been used in blast furnace repairs.
Kerapump 7 has largely replaced Kerapump 3. It has a very high tolerance for "abuse" on site, and can be used over a wide range of water contents. It is very fine and we make thin walled insulating coffee mugs from it just to demonstrate how good it is.
Ladles are very large refractory lined pots for transporting molten metals. In steel plants they carry in the region of 70 tons of molten steel. They are mostly transported by overhead cranes. Imagine one of them springing a leak! Well, it happens. It happens frequently.
Every time it happens, there is an investigation, and I am always very sceptical of the conclusions. The conclusions always strike me as being the only possible theoretical explanation anybody could come up with, even though it seems rather far fetched.
If molten steel finds a crack leading to the steel shell of a ladle, it will run through and freeze almost instantly. The only breakout explanations that hold any water are those in which the steel continues to flow against the shell. This necessitates a cavity or labyrinth of cracks in contact with the shell. Mike Moore of Richards Bay Minerals discovered that when he increased the capacity of his ladles, the pressure against the shell increased, as evidenced by the insulation being crushed. This had me puzzled for some time. The explanation is as follows; The total outward movement of the refractory lining is determined by the highest expansion. The highest expansion is on the hot face. The larger the diameter of the hot face, the greater the movement outwards of the lining. The hot face of the bricks on the working face expands and the bricks push each other away. The colder bricks are in turn pushed outwards, but they do not expand as much. It follows that the colder bricks are no longer in contact with each other, but are separated by small gaps.
The chances of steel getting into this labyrinth of gaps is small, but it does happen. Note that the pressure forcing it in is enormous. 2" metres of molten steel has a pressure equal to 20 metres of water.
From my explanation, it follows that you can build a ladle lining absolutely perfectly free of cavities, but once you heat the hot face, it will contain a labyrinth of gaps in contact with the shell. The solution is dead easy. As soon as the ladle is hot for the first time, pump some Kerapump 3 through nipples in the shell, and it will fill all the gaps. No gaps in contact with the shell means no possibility of a breakout. There we have the solution to saving countless lives worldwide and millions of rands of equipment. I wonder if anyone will ever listen? If I were a mason building ladles I would certainly latch onto an explanation of how my perfectly solid linings can leak. Would't you?
Our business still revolves mainly around solving problems. We get far more enquiries nowadays than we can handle. We try to attend to them according the following priories.
1. Firm orders
2. Established customers
3. Cash customers
4. Those who pester us the most.
5. Those problems which are technically the most interesting.
Usually we can supply materials off the shelf that are more appropriate than anything made by the bulk manufacturers. We are getting the bulk of our sales today through agents, other refractories manufacturers, suppliers and installers. We like it that way, as we do not have our own salesman.
My landlord, Hennie Maree, has a 35 cubic foot pottery kiln to sell. It opens both sides, and has never been over fired. Tel. 692 1657.