Keramicalia

Tel: +27 (0)11 412 3261 or +27 082 808 4757
We manufacture specialised refractories and ceramics.

Miscellaneous

Some of these products are imported, others sourced locally, and stocked at Keramicalia.

Papers;
Ceramic fibre paper is stocked in 1mm and 3mm thick.
Ceramic fibre paper is stocked in 1mm and 2mm thick.
Mica paper is sometimes stocked.
Ceramic pipes/ tubes;
We keep a lot of ceramic tubes, thermocouple sleeves, beads etc. mostly 5mm to 25mm O.D. and 100mm to 800mm long.

Porcelain;
We do some porcelain and cordierite specialties

Loose fibres;
We stock coarse polypropylene fibres, fine cellulose fibres, “Granulated ceramic fibres,” water soluble glass fibres and RFT fibres( (rapid fire technology)

Markers;
We manufacture cobalt oxalate Crayons which make an almost unreadable pink marking, which turns black at 300°C and then bright blue at 1000°C. The marking therefore tells you whether the sample is air dry, cured or fired. We also manufacture wax crayons with iron oxide or manganese oxide pigments. A few temperature indicating crayons are normally available. These are brilliant for measuring surface temperatures.
We supply stamping inks in chrome oxide green and cobalt black.

Metals;

We normally have small stocks of expanded metal and hexmetal, and some stainless steel melt extract fibres. We supply some custom made chills and ingot moulds.
keracomp is a steel fibre- ceramic composite which works in those extremely arduous applications where both refractory and metals fail.

We are offering Ferrosilicon balls in various sizes, but have not yet found a market.

We manufacture Orton pyrometric cone sets.
High temperature grease is another obscure product which we make.

Electrical;
In line with our “one stop furnace shop” policy we now stock programmable controllers, set point controllers, thermocouples, elements and line taps.
We manufacture most of the components for kilns, and can supply off the shelf all you need except the steelwork for your furnace.
We manufacture electric incinerators for hospital wastes.
Sometimes we have safety equipment.
We have 23 years worth of contacts from America to Zimbabwe where we source specialities.

 

Baking Trays

“Baking trays” are actually slabs for lining stainless baking trays.   They are made of a refractory material designed for the highest possible thermal mass.   In other words they retain a lot of heat.   If you place pastry directly onto hot steel it burns, especially the edges.   Baking trays distribute the heat evenly and regulate the speed of heat flow into the pastry.   The density is very high, about 2.8kg/litre.   Baking trays have a layer of fiberglass scrim in the middle, so that if they crack they do not break.   They are also used in electric pizza ovens. The surface is porous and can absorb fats.   The top surface on which you bake is smooth and the bottom surface is rough.

The sizes are 15mm, 20mm and 25mm thick.   Slabs are cast to order, to fit your oven, so there is no cutting and wastage.     25mm slabs are mainly used as pizza oven floor tiles, and 500mm x 500mm tiles are kept in stock.   50mm tiles are used as Coke Whorf Tiles, which get covered with yellow hot burning coke which then gets quenched with water.   The thermal shock resistance spec is 900°C into water 30times without breaking.   900°C is the maximum continuous service temperature, but the material can withstand 2000°C for the short retention periods of hermit reactions, because crucibles of this material can absorb and dissipate so much heat.

The color is dark brown and the top surface is smooth enough to show reflections.   The particles are coarse. Baking trays can be trimmed or cut with difficulty with an angle grinder,   but easily cut if you use a diamond blade.

Buzz Off

Buzz Off is a dangerous highly flammable pyrotechnic material for use only in emergencies.  It is used to drive unwanted bees from an inaccessible hive.  It will usually kill most of the bees.  The smoke contains hydrochloric acid, which can cause serious corrosion.

Before deciding to use Buzz Off, consider the following alternatives; Will a beekeeper perhaps remove them for you?

Can you seal up the nest?  If you can, do so immediately after the bees have moved in, otherwise you may have problems and smells arising from the decaying matter.

Consider the probable shape and extent of the cavity. Is there likely to be flammable material in the cavity?  Don't consider using it in a roof. Are there any plastic electrical conduits passing through the cavity? Does the cavity open into your house?  If so, block off all possible openings.

Before using Buzz Off, light a teaspoonful in a safe place so you can see what heat and smoke you will be applying.

Use Buzz Off at night when the bees are inactive. Be alert for live bees crawling on the ground outside afterwards, and bees attracted to a light during the night.

Buzz Off ignites very easily and requires no oxygen to burn.  Do not compact it, as it may explode. Store out of reach of children and away from heat and electricity.  Buzz Off and its residue are poisonous to plants and animals and people.

Dev No: 16500

Ceramic fibre paper

DESCRIPTION

Aluminosilicate thermal insulation paper.   Good thermal stability and excellent thermal shock resistance, good chemical stability and tensile strength, low heat storage.

APPLICATIONS

Backup insulation, furnace door seals, thermal shock protection, parting medium, increasing reflectivity.

CHEMICAL ANALYSIS (%)

AI2O3                                                   46

SiO2                                       51

Fe2O3                                    1.0

Na2O3 + K2O                         0.5

CaO+MnO2  + TiO2

+ Trace elements                  1.5

PHYSICAL PROPERTIES

Maximum continuous service temperature         1260°C 

Colour                                                   white

Bulk density                                       160kg/m3

Thermal conductivity (mean value)                                                  at 260°C             0.06W/m.K

                                                                                                at 400°C                                0.08W/m.K

                                                                                                at 600°C                                0.1W/m.K

                                                                                                at 800°C                                0.12W/m.K

                                                                                                at 1000°C                             0.2W/m.K

PACKAGING                       sold per square metre. 

Full rolls in cartons with plastic liner:       1mm x 40m x 610mm

                                                                                3mm x 20m x 610mm

                                                                                6mm x 10m x 610mm

1220mm rolls available on order.

Dev No: 71400

HEALTH & SAFETY           Harmless before use, wear mask when removing used fibre.

Crayons

We make marking crayons in two types, wax based and ceramic based.

The wax based crayons work well on coarse bodies like abrasives, an d the pigment is black iron oxide which persists after firing to high temperatures.  Other colours can also be made.

The ceramic crayons can be made in various colours from frits, and are wax free, suitable for underglaze.

The most popular crayon is cobalt oxalate based.  It writes pale pink, almost invisible on green ware.  After tempering at 400 degrees, it shows up black, and after firing it comes out cobalt blue.  It can therefore be used to track the identity of an item and also its firing status.

Dev no: 21800

Graphite Paper

Induction furnaces are convenient and safe except for one problem;

If molten metal reaches the coils there is tremendous steam explosion which can result in fatal injuries and great expense.

Electrical detection of metal via the spider and the coil give warning, usually in time to stop an explosion, but usually too late to prevent extensive damage.

The coils are normally encapsulated in high alumina refractory, then a parting layer of millboard or mica paper is placed over them, and a dry spiking refractory rammed firmly into place with a metal former for the inside.

Instead of millboard or mica paper, we offer graphite paper.   Graphite paper is electrically conductive, and it must never touch the coils.  

It is an excellent parting agent, and since it has a low coefficient of friction it assists compaction of the rammed mass.   It is fitted in contact with the spider, but not the coils.   The spider can now detectmetal contact before the metal even reaches the coil coating, and the furnace can be shut down before any damage is done.   The rammed lining comes out easily and the coil coating is unharmed.   Usually the graphite paper can be reused several times.

Graphite paper comes in rolls 1metre wide and 1mm thick.   It is very flexible.   If you close off the outside of the coils, you can make a former for the graphite paper and pour Keratab Ultrafine between the coils.   Keratab Ultrafine is a powder which flows like thick cream when mixed with +16% water.   It contains 93% alumina.

Graphite paper may not be used as a continuous sheet next to the coils,

as it will heat up by induction.   It is therefore supplied in sheets

consisting of 100mm strips joined with tape such that the strips of

graphite are 10mm apart.   The paper must be installed with the graphite

strips aligned vertically, to avoid inductive heating. 

See also Induction Coil Coating and Keraplas.

Dev.No: 47350

keracomp

Description:   The name is a contraction of "Keramicalia composite material of ceramic and stainless steel fibres." Ceramics are all brittle but many have high melting points, whereas metals are non-brittle but oxidise or melt at high temperatures. Some difficult metallurgical applications are not satisfied by either ceramic or metals, but require properties of both. Keracomp is designed to meet this need.

The fibres are compacted into a mould in the highest concentration possible, and a thin ceramic slurry is infiltrated into the matrix between the fibres. On heating, the structure develops millions of micro-cracks due to the differential expansion of steel and ceramic, but the microstructure is interlocking, making it extremely difficult to break mechanically.

Think of it as a three dimensional jigsaw puzzle: It is not a solid material but millions of tiny interlocking pieces. It can be stretched or deformed without breaking and no stress points can be formed for tearing of cracking because the structure is already in millions of tiny pieces.

Maximum service temperature:  Keracomp can be used at high temperatures as long as there is a thermal gradient. The whole structure should not be surrounded by heat without any source of cooling.

The chemical analysis may be varied to suit the application, but is typically about 85% alumina ceramic and high nickel content stainless steel.

Physical properties cannot be tested by conventional ceramic and refractory procedures, nor by normal metallurgical tests. The reason for this is that the material is not a solid, but is already broken into tiny pieces. In the cold crushing strength test the cube does not break. Densities are around 3 tons per cubic metre.

Applications:  Nearly all applications in which refractories and steels are both known to give poor performance. Keracomp can be attached to steel.

 Installation: Pack fibres as densely as easily practical into the mould.   Add +22% water to the Keracomp Slurry powder and mix well until it becomes a smooth creamy pourable fluid.   Pour it over the fibres and allow it to penetrate completely.

Pilot Plant code;  

Dev. no. 206 and 1011

Keralith

A very low thermal expansion ceramic based on lithium aluminium silicate.

It is used in places where it has to resist extreme thermal shock, and places where the integrity of a structure can only be maintained if there is almost zero thermal expansion.

It is lightweight, insulating and strong.   The bulk density is 1,8kg/litre.

The apparent porosity is 24 volume %.

The modulus of rupture is around 30MPa.

The coefficient of thermal expansion is 0,3 x 10-6/C, about a tenth of the average for ceramics.

Keralith can be used at up to 1220°C.

Thin walled ceramics can be made in Keralith.  It is slip cast and fired.

Development no.  87605

keratex

Keratex is a woven aluminosilicate cloth, reinforced with fine nickel-chrome wires.    Conventional refractory fibre blankets are either asbestos based or have organic material woven in.   Keratex is completely asbestos free.   Keratex contains less than 2% organic matter.   It is very strong, flexible and light.   Keratex can withstand 980°C.   It is normally used as a screen for radiant heat from temperature sources much higher than 980°C, but the textile itself seldom reaches its temperature limit.

Keratex remains flexible at high temperature.   It only breaks down slowly by abrasion.   It does not shrink.   It has very good chemical resistance.   It is only attacked by hydrofluoric acid, phosphoric acid and strong alkalies.   It is not affected by water and steam.   Screens are not impervious, but stop most of the air flow through them. 

Applications:   Curtains to limit convection air flow at furnace doors.   Curtains to separate different heat zones of furnaces or ovens.   Screens to shield operators from radiant heat.   Temporary screens for operators during gunning and hot repair.   Protection of hot floors during gunning or other repair.      Entrance and exit barriers in continuous heat treatment processes.

Width:  980mm.   Roll length:  42m.

Strips can be stitched with thin element wire.

Dev no:                1200

Miscellaneous

Some of these products are imported, others sourced locally, and stocked at Keramicalia.

Anti Theft Materials:

We make castables to resist burglars.

Safe Reforcing. We sell various materials for you to concrete.  We make a cable theft prevention cement for cable trays.

Buzz Off destroys unwanted bee hives.

Ceramic pipes/ tubes:

We keep a lot of ceramic tubes, thermocouple sleeves, beads etc. mostly 5mm to 25mm O.D. and 100mm to 800mm long.

 Electrical:

In line with our “one stop furnace shop” policy we now stock programmable controllers, set point controllers, thermocouples, elements and line taps.

High Temperature grease:

High temperature grease is another obscure product which we make.

Incinerators:

We manufacture electric incinerators for hospital waste.

keracomp:

keracomp is a steel fibre-ceramic composite which works in those extremely ardous applications where both refractory and metals fail.  We make Hand held lances from Keracomp.

KeralithIs an ultralow thermal expansion material with which we do prefired castings.

We manufacture most of the components for kilns, and can supply off the shelf all you need except the steelwork for your furnace.

Loose fibres:

We stock coarse polypropylene fibres, fine cellulose fibres, "Granulated cermaic fibres", water dispersable glass fibres and RFT fibres (rapid fire technology).

Markers:

We manufacture cobalt oxalate Crayons which make an almost unreadable pink marking, which turns black at 300°C and then bright blue at 1000°C.   The marking therefore tells you whether the sample is air dry, cured or fired.   We also manufacture wax crayons with iron oxide or manganese oxide pigments.   A few temperature indicating crayons are normally available.   These are brilliant for measuring surface temperatures.
We supply stamping inks in chrome oxide green and cobalt black.

Metals:

We normally have small stocks of expanded metal and hexmetal, and some stainless steel melt extract fibres.     We supply some custom made chills and ingot moulds.

 Papers:

Ceramic fibre paper is stocked in 1mm and 3mm thick.
Graphite Paper is stocked in 1mm and 2mm thick.
Mica paper is sometimes stocked.

Ceramic pipes/ tubes;
We keep a lot of ceramic tubes, thermocouple sleeves, beads etc. mostly 5mm to 25mm O.D. and 100mm to 800mm long.

Porcelain:  We do some porcelain and cordierite specialties

We are offering Ferrosilicon balls in various sizes, but have not yet found a market.

Pyrometric cones:

We manufacture Orton pyrometric cone sets.  They measure cumulative heat treatment rather than just temperature.

Safety equipment:

Sometimes we have safety equipment in stock.

Textiles:

Ceramic Fibre Blanket is always stocked in 96kg/m³ 25mm thick 1260ºC.  It comes in rolls of 7m x 610mm.

Geotextile is a non woven fabric used as a carrier for Keraforce.  A thinner carrier is SBP.

keratex is a woven composite of ceramic fibre and thin stainless steel wire.

skin safe is itch-free rockwool

We bring in graphite felt for vacuum furnaces.

 

Safe Reforcing

There are ways to combat every type of attack that can be applied to a safe.

  1. Moving it is the most simple mode of attack. To prevent this, the safe must be as heavy as practical, be attached as well as possible to the structure in which is housed, and have no access points for lifting devices.
  2. Blasting: The principles of steel reinforcing are applied, where “re-bar” has good tensile strength and concrete has good compressive strength. There must not be access holes for dynamite, and drilling of holes must be as difficult as possible.
  3. Drilling: The material must be a composite of mineral and steel. The mineral component defeats  a steel drill and the steel defeats a carbide drill. The addition of porcelain balls is highly beneficial to defeat both steel and carbide drill tips.  Balls are seldom contacted head on so the drill is also deflected. Corundum, with a hardness of 9 on the Moh Scale is a popular aggregate. The addition of a bit silicon carbide, 9, 5 on the Moh Scale really messes up drills. Fine zirconia toughened alumina balls are very resistant to drilling and grinding.
  4. Grinding: The same principles apply as for drilling. The addition of sulphur helps. It melts and lubricates the blade.   It also gives off nasty fumes. Aluminium chips clog up a blade.
  5. Thermal lancing: Portland cement is replaced by calcium aluminate cement which has a very high melting point. Use corundum aggregate with a melting point of 2013°c. A high thermal mass aggregate helps a lot, as it absorbs the heat.  Pizza Oven Floor mix is designed for high thermal mass, and is also very heavy. If plastic packets of thermit powder are added to the mix they will endanger the life of the burglar, but also create a serious fire hazard.
  6. Impact: Keracomp is a composite of ceramic and steel fibres which is almost indestructable by impact.

skin safe

We are now importing a French rockwool product that DOES  NOT  ITCH!!    It is made by a new

process in which no shot is produced.

You can rub it on your face!

We will be stocking soft boards  1,2m x 600mm x 25mm @ R244 ea

and rolls of wired mattress   5m x 1, 2m x 50mm, ready to wrap around tanks etc. @ R2298/roll