Pumpable materials can be installed into inaccessible places, or can be mixed far from the site of installation and pumped, usually a high vertical distance to their point of application. All very fine materials can be pumped, but only carefully designed ones keep their volume after drying, without shrinking. Pumpable materials are not necessarily self-flowing materials. The most versatile pumping materials are self levelling, insensitive to water addition, do not segregate, and do not shrink. They may be strong or soft, dense or insulating. The Kerapump range contains a variety of materials, mostly cellular insulation.

* Kerapump 1 is a high strength, very fast setting material.
* Kerapump 2 is a very soft injectable material, mainly used in compensators, which can be poured.
* Kerapump 10 is a general purpose insulation material. It is also used in moulding, for its good machinability.
* Kerapump 4 is a medium strength cellular insulation material.
* Kerapump 5 is a very light precision casting material for components traditionally made from Marinite or calcium silicate.
* Kerapump 6 is a dense andalusite pourable material.
* Keraject and Rubyject are dense alumina pumping or injection materials. “Injection” is pumping of material through a furnace shell into a cavity. See Injection Repairs


Ceramic fibre in pumpable form with no binder.

Applications: For installing ceramic fibre in places only accessible by pumping, where it is left completely loose and free to compress and expand with movement. It was developed as insulation for bellows.

Maximum service temperature: 1260°C.

Composition: Ceramic fibre, water and 2.8% organic suspension agents.

Wet density: 0.58g/cm³

Chemical analysis (%) Fired:

Al2O3 46%
SiO2 51%
Fe2 O3 10%
Na2O3 + K2O 0.5%
CaO+MnO + TiO2+ Trace elements 1.5%


Installation: Supplied ready mixed, wet, in buckets. Can be pumped by silicone gun, pneumatic mastic gun, squeeze pump, peristaltic pump, diaphragm pump, piston pump, auger pump or Mono pump. The cavity must be vented to release steam. Pumping can be done hot or cold.

Packaging: 5kg in 10-litre plastic buckets with liners.

Handling: Totally harmless while wet, respiratory hazard when dry, treat as used ceramic fibre (irritant) after firing.

Shelf life: 2 years.

Development no. 146700

Injection Repairs

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.


Description: Keraject is an injectable hot repair material. It is used for repair of furnaces without a shutdown. Keraject comes in various chemical types, including carbon, aluminosilicate and basic. The insulation types are called Kerapump. Keraject is a very dense cohesive material, with a long working time and a very rapid heat set.


Rotary kilns: Hot spots on rotary kilns can be very costly. Downtime for repairs from the inside can be weeks. If external water spray cooling is practiced, some distortion of the shell generally results, and the hot spot generally grows larger. Repair with Keraject is done with virtually no stoppage of production. Nipples are welded onto the shell at the hot spot. Holes are then cut through the nipples. Keraject is then pumped through the shell. It lifts the burden and fills the void behind the hot spot. At no stage is the kiln stopped for longer than 30 minutes.

Furnace floors: Billet reheat furnaces sometimes suffer extreme abrasion wear. The floors can be repaired by pumping Keraject onto the surface. Gunning has also been used successfully in this application.

Blast furnaces: Sidewalls at various levels can be repaired during minor shutdowns.

Arc furnaces: Repairs can be done if the furnace contains largely solid but unconsolidated material.

Installation: The material is mixed in a Putzmeister pump and injected through nipples in the shell. The pump is very powerful and can pump to great heights and exert considerable pressure on the furnace charge.

Kerapump 10

Description: A pourable or pumpable insulation refractory. It is extremely fine and can be used for precision cast and detailed components. It can also be machined.

Maximum services temperature: 1150°C


110°C 7-12Mpa
400°C 10-15MPa
1000°C 6-10MPa
1200°C 15-25MPa


Density: 1.15g/cm³

Thermal conductivity: About 0.4W/mK at 600°C

Chemistry: Aluminosilicate cellular insulation.

Water addition: +40% by weight.

Coke ovens pumping behind flashplates.
Blocking gas tracking.
Synthetic coals for gas fireplaces.

Chemical analysis:

Al2O3 34%
Fe2 O3 1.0%
Cr2O3 0.04%
SiO2 37%
TiO2 1.5%
Ca2O3 16%
MgO 0.5%
Na2O 0.6%
K2O 1.3%
MgO 0.5%
P2O5 1%


Packaging: 10kg plastic bags

Kerapump 5

The permanent linear change measurements on Kerapump 5 are as follows; (Taking air dried dimension as 100%) 110ºC -0.15% 400ºC -0.45% 1000ºC -1.7% 1200ºC -2.4%

Chemical Analysis:

Al2O3 48.0%
SiO2 36.0%
Fe2 O3 1.0%
CrO 0.09%
TiO2 0.7%
CaO 10.0%
Na2O 0.7%
K2O 0.8%
P2O5 1.1%
MgO 0.5%
L.O.I 1.5%
Total 100.39%

Kerapump 6

Description: A high density self flowing pumpable aluminosilicate. It flows well and de-airs itself down to 1mm bubbles at +10% water addition. It has almost no tendency to segregate.

Density: Wet 2.7g/cm³

Installation: Add plus 10% water, mix until self levelling and pump or pour into place. It penetrates well and de-airs itself.

Applications: Difficult access situations where a strong dense refractory is required.

Packaging: 25kg plastic bags on 1 ton pallets stretchwrapped.

Development no. 37706 Pilot Plant code;

Chemical analysis:

Al2O3 40.9%
Fe2 O3 1.1%
SiO2 54.4%
TiO2 1.61%
CaO 0.37%
MgO 0.58%
Na2O 0.5%
K2 O 0.44%
P2O5 0.0%
L.O.I 0.90%
Total 100.35%


Description: Aluminosilicate ceramic fibre in pumpable form, supplied wet ready to use. Very easily applied to any surface.

Emergency repairs.
External hot repairs.
High temperature insulation
Heat shields
Thermal shock protection
High gas flow areas of fibre lined furnaces
Repair of cracks and joints
Protection of equipment
Protection of electrical cables.
Reduction of thermal mass.
Upgrading of linings for thermal efficiency or faster cycle times.
Sealing of kiln and furnace doors
Lightweight doors.

Very low thermal conductivity; 0.2W/mK.
Electrically insulating.
Very low density; 0.7g/cm³ wet, 0.45g/cm³ dry.
Low shrinkage.
Extreme thermal shock resistance.
Very low thermal mass.
High reflectivity.
Low permeability compared to fibre blanket or modules.
High reflectivity.
Rapid commissioning.
Excellent adhesion to all surfaces.
Minimal anchoring required.

Chemical composition:

aluminosilicate  85%
Fe2O3             < 0.3%
Alkalis                0.2%


Maximum service temperature: 1300°C

Packaging: Refpump is supplied wet in plastic 10litre buckets with plastic liners. 6kg per bucket.

Shelf Life: 3 years