GRAPHITE

We have several graphite products:

Graphite Paints:For sliding Gates. For lubrication 4908 Data Sheet.

Electrically Conductive Paint: mainly used to prepare for electroplating.

Graphite Die Coating: Very good stuff !

Oil based graphite paint: for release of molten metals poured into steel chills.

Decorative graphite paint. Included here because it is the purest graphite paint, coarse flake supplied as powder

Graphite block: big chunks of Graphite from which to machine components.

Graphite castable: Used for stopper rod heads, crucibles etc.

Graphite ramming: We supply this, but the lead time is sometimes long

Flake Graphite: We stock natural flake graphite.

Graphite Felt: Half inch and quarter inch. Terribly expensive ultra-high temperature insulation. For reducing conditions only.

Graphite Glue: Used as part of our crucible repair technique. Heat Setting

Graphite Grease: For lubrication in die casting and tunnel kiln wheels.

Graphite Paper: For high temperature gaskets

We can also supply recarburiser, we have a supplier of precision machined graphite parts.

Crucible Patch: A graphite based crucible repair material, col setting.

Hot Contact : A graphite based paste, Heat setting for providing thermal contact eg. Between heating pipes and retorts. We also make a Hot Contact Cold Setting version.

Graphite rubbing blocks: Stops metal wear eg. On rotary kiln tyres.

Graphite insulation boards: Redundant stock of horrifically expensive product going very cheap.

Graphite paste: A parting layer used in ingot casting.

Graphite Pencils: The only graphite product I can think of that we don’t sell.

Graphite Paint

 

A high temperature lubricant based on natural flake graphite.

Principles:

Graphite is a natural form of carbon consisting of layers of closely spaced carbon atoms, and a very large space between the layers.   This gives it different properties if measured in different directions.   It also allows the layers to slide relative to each other, and this makes it nature’s perfect lubricant.   It is rather difficult to make a paint out of graphite, but it is possible.   Graphite paint is a coating which is not fixed in place.   It will move if something slides across it.   It is pointless to try to get a graphite paint smooth.   The paint will redistribute itself to fill voids.   The important thing is to have enough thickness of paint to be able to fill voids and still cover the highest protrusions.   The thickness of coating required is therefore a few microns on flat polished surfaces and several millimeters on rough refractory castings.  

Applications:

Lubrication of surfaces where refractories need to slide over each other or against steel.   It was developed for sliding gate plates where the refractories are pressed against each other under very high pressure and the temperature reaches 1650°C.  Used on doors, undercuts on very damaged casting dies, crack filling in almost unusable ingot moulds.

Composition:

High quality natural Ceylon flake graphite with binders, carriers, wetting agent and biocide.

 Maximum service temperature:

1000°C in exposed oxidizing atmospheres.

2000°C in reducing atmospheres.

 

Appearance:

 A grey-brown paste.

Density:

1,5 kg/litre

Painting:

Graphite Paint sticks to all surfaces except polyethylene.   Preparation of substrate is only necessary if there is a lot of oil, grease etc. present.  Small gaps in the coating are not a problem, they will get smeared over in use.   Drying will be rapid on porous refractory surfaces, much like normal paints on steel.   Sprayed Graphite Paint looks neat but works no better than very badly brush painted graphite.  

Toxicity:

All components are harmless and eye contact or accidental ingestion are no cause for alarm.   Graphite paint poses no environmental threats or hazards.   It is hover dirty, and you should wear overalls if applying large quantities, and if they get very dirty, wash them separately.

Packaging:

10 kg in plastic buckets.   Brush painting will coat about 4mm thick.   Add water to get the desired thickness appropriate to the surface roughness.

Track record:

The formulation has changed little since 1988, and no application has been encountered where it has failed.

Shelf life:

About 5 years.   Add water if too thick to paint.

Development no. 4908

Electrically Conductive Paint

 

Description: 

A black ink based on Ultrafine flake graphite and chemicals.
Dip or paint it onto a surface which you want to make electrically conductive. Perfect to enable electroplating.  Multimeter registers a dead short.
Coverage:
Ceramic consumes about 200g/m².  Smooth impervious surfaces consume less.

Packaging: 

Any size container you want.
Price 2019:    

R2200/kg  (5 to 15 m2)

Development No: 163702

Graphite Die Coating

 

Graphite Coating for Gravity And Low Pressure Die-Casting

Description 

Graphite Die Coating is a homogeneous liquid consisting of carefully selected graphite’s, which have undergone thermal and chemical treatment in order to achieve maximum efficiency in the field of gravity- and low pressure die-casting. 

The prime function of a graphite die-coat is that of lubrication. Graphite Die Coating accomplishes this objective, as it is comprised of a highly heat-resistant graphite matrix, which resists oxidation at elevated temperatures and maintains its adhesive qualities. In this way an above average number of castings can be produced without the need for continuous re-spraying. 

The two other important functions of a graphite die-coat are those of producing a smooth casting surface finish and preventing cold flow. The graphite matrix contained in Graphite Die Coating consists of a particle size distribution, tailor-made to achieve these two functions. 

Applications 

Graphite Die Coating in diluted form may be applied to: 
die cavities (to be sprayed on top of refractory coating) cores and moving parts of the machine
Dilution Ratio and Mode of Application 

Graphite Die Coating should be diluted with tap water prior to use at a ratio of 1:5 to 1:12 depending upon the velocity of the spray system used in the application. Some agitation is required during the dilution process. 

Once diluted, Graphite Die Coating should be applied by means of a suitable spray gun. The metal surface to which the diluted Graphite Die Coating is to be applied should be pre-heated to at least 100° C (approx. 200° F) 
 

Graphite Glue

 

Description:  A glue for repairing clay-graphite crucibles.
Application:  Mix powder and resin to desired consistency. 2,8:1 powder to liquid is a nice paste.  

Apply to both surfaces, rubbing it in well.  Stick the surfaces together as tight as you can. Smear a thin layer over the joint. Heat up to about 250°C to cure it.
Maximum service temperature:  1000°C exposed to air, higher under reducing conditions or covered by molten non-ferrous metals.
Repair is very effective for low temperature metals, for aluminium it should be used in conjunction with scrim and Alusmear. Not recommended for use over 900°C


Development no.1300

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 detect metal 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
 

Hot Contact

 

A  highly thermally conductive plaster to ensure conduction of heat between surfaces.   The commonest application is between trace heating pipes and the pipes to be heated.   It is very important to get the tightest possible contact between the two pipes.   The surface contact area is then increased by plastering  the gap between them.   The plaster should cover over the trace heating pipe to a thickness of half the pipe diameter and then fill the sides at a 45° angle to cover the target pipe over a contact area three times the diameter of the heating pipe.   If the heating pipes are close together, the whole area between them should be filled.

 
Hot Contact is heat setting.   It stays workable even at 110°C overnight, and only sets rapidly above 150°C.


Hot Contact plaster consists of two parts;  a black powder and a black liquid resin.   They are mixed in the ratio of two weight parts powder to one weight part resin.   It is heat setting, so the pot life is several days.


Before applying Hot Contact, clean the pipe surfaces of any dirt, paint, oil, grease or thick rust.   A thin layer of rust is acceptable but paint is not acceptable.


Hot contact is VERY dirty to work with.   For any large job, wear disposable paper overalls and rubber gloves.   Plastic boot covers are also worthwhile.    Have a few spare pairs of rubber gloves handy in case you need to rub your nose or get something out of your pocket.


Fortunately it can be washed off with water before it hardens.   Ceramic fibre blanket makes a handy disposable scouring cleaner for trowels and mixing containers.


Shelf life is about 10 years.   Store in a cool place if possible, where containers are not likely to get damaged, because leaks are very messy.


After installation, heat the traces and examine the contact area.   If the traces have come loose from the target pipe anywhere, due to thermal expansion of the trace pipes, keep the trace pipes hot while injecting Hot Contact into the gap with a mastic gun.


Hot Contact is not hazardous, just very black and messy.


Development no. 147301.

Hot Contact, Cold Set

 

A  highly thermally conductive plaster to ensure conduction of heat between surfaces.   The commonest application is between trace heating pipes and the pipes to be heated.   It is very important to get the tightest possible contact between the two pipes.   The surface contact area is then increased by plastering  the gap between them.   The plaster should cover over the trace heating pipe to a thickness of half the pipe diameter and then fill the sides at a 45° angle to cover the target pipe over a contact area three times the diameter of the heating pipe.   If the heating pipes are close together, the whole area between them should be filled.


Hot Contact Cold Set hardens in around half an hour. You have 15 minutes to work with it. 


Hot Contact Cold Set plaster consists of three parts;  a black powder, a red liquid resin and a clear liquid activator.   They are mixed in the ratio of two weight parts powder to one weight part resin and one fifth part activator.   Mix the activator in last.
Before applying Hot Contact, clean the pipe surfaces of any dirt, paint, oil, grease or thick rust. A thin layer of rust is acceptable but paint is not acceptable.


Hot contact Cold Set is VERY dirty to work with. For any large job, wear disposable paper overalls and rubber gloves. Plastic boot covers are also worthwhile. Have a few spare pairs of rubber gloves handy in case you need to rub your nose or get something out of your pocket.


Fortunately it can be washed off with water before it hardens. Ceramic fibre blanket makes a handy disposable scouring cleaner for trowels and mixing containers.


Shelf life is about 4 years.   Store in a cool place if possible.Keep away from sunlight.  Store where containers are not likely to get damaged, because leaks are very messy.


After installation, heat the traces and examine the contact area.If the traces have come loose from the target pipe anywhere, due to thermal expansion of the trace pipes, keep the trace pipes hot while injecting Hot Contact Cold Set into the gap with a mastic gun.


Hot Contact Cold Set is not hazardous, just very black and messy.


Development no. 147310.

Graphite Paste

Ingot moulds deform from thermal cycling, and eventually develop cracks big enough to prevent the ingots from releasing.

These cracks can be patched with Graphite Paste.

Do it while the mould is warm, so that it is completely dry in less than a minute.


Development no.8003

CONTACT US

Tel: (011) 412 3261

Corner Steyr & Alfa Sts ,Aureus Industrial sites, Randfontein

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