Keramicalia

Tel: +27 (0)11 412 3261 or +27 074 587 2728 Fax: +27 (0)11 692 1232
We manufacture specialised refractories and ceramics.

Plastics

Plastics are putty-like materials. They are easily placed in small quantities and generally have high strength and abrasion resistance. The most popular are phosphate bonded chrome-alumina materials called Keraplas.

Kerapatch Stainless is the same but cheaper, without green chromic oxide addition.

Induction Coil Coating is a hydralic bonded alumina material for induction furnace coils and embedding elements onto muffles.

Hollocast  a cellular insulation material, can also be used in plastic form.

Several grades of Versimould quick setting materials are used in plastic form, for sealing, blocking cracks prior to pumping repair, and hot repair of furnaces.

Kerapack A is a phosphate bonded alumina for packing into hexmetal.

Kerabrade 60 is an abrasive resistant plastic supplied dry.

Hollocast

Hollocast is the castable group of cellular insulation materials . They are strong insulation materials with largely sealed porosity .

Hollocast 1 is the general purpose castable, which is very user-friendly. It has an excellent track record in a very wide variety of applications.

Hollocast 2 is a low cement variety designed for pre-fired components, giving lower creep in load bearing kiln furniture.

Hollocast 3 contains barium, for aluminium furnaces.

Hollocast 4is based on bubble alumina and Hollofill.

Hollocast 5 is based on bubble alumina and is totally silica free.

Hollocast 6is based on a calcium aluminate foam with a composition of which is highly refractory . It is the best insulation material for 1500°C.

No.

Density

Maxinmum Service temp

Price / Kg 2017

Silica Content

Water Addition

Development

No.

1

1,5

1400°C

R29.00

41,3

+20%

55597

2

1,5

1350°C

R29.00

±43%

+17%

32904

3

1,7

1500°C

R29.00

±38

+14%

108501

4

1,2

1500°C

R53.00

7,2%

+16%

40330

5

2,1

1700°C

R75.00

±0,1%

+8%

40329

6

1,1

1500°C

R132.00

±0,05%

+60%

41645

Induction Coil Coating

  Description A high density plastic alumina refractory. It has high strength and abrasion resistance and good electrical insulation once dried.

InstallationSupplied as powder, to which +12 to +13% water must be added for a putty consistency, or more water for a soft coil embedding consistency.

ApplicationsAreas where combinations of high strength, abrasion resistance, high thermal conductivity and zero electrical conductivity are required. Main uses are; Filling the spaces between induction coils, Embedding elements around muffles.
 

Chemical Analysis

Al2 O3 97.0%
Fe2 O3 0.01%
SiO2 0.01%
CaO 3.0%
Na2 O 0.25%


Colour: White

Maximum particle size: 1mm

Packaging: 25kg plastic bags

Shelf life: 18 months

Development number: 24698

See Keratab Ultrafine; Similar material, self-flowing and self-levelling.

Kerabrade 60

Description; An abrasion resistant refractory installed in plastic form. used between 200ºC and 1000ºC. The matrix is hard and does not wear much faster than the aggregate.

Density; 2,5g.cm³

Cold Crushing Strength; 120 to 180 MPa (after 800ºC)

Thermal conductivity; 1.8W/mK

Permanent linear change after 800ºC; -0.35%

Maximum particle size; 5mm.

Chemical Analysis;

Al2 O3 54.0%
Fe2 O3 0.6%
SiO2 44.0%


Installation; Mix the powder in high shear mixer, preferably a bakery type planetary mixer for 1 minute. The add +5.3 to +5.8% water and mix for about 5 minutes. it will reach a plastic consistency suitable for hand packing. Normally it is placed into hexmetal reinforcing.

Packaging; 25kg plastic bags.

Kerapack A

Description: Alumina patching material with high density and plasticity. Good electrical insulation. Good abrasion resistance.

Applications: Coating and filling between induction coils. Moulding electrical components. High temperature abrasion resistance. Embedding and covering of elements.

Maximum service temperature; 1800ºC.

Consistency: With +12% water it is a putty -like consistency. The watyer addition may be varied to make it stiffer or softer. Setting is rapid and strongly exothermic

Composition; over 90% alumina, silica free.

Colour; White.

Packaging; 25kg plastic bags.

Kerapatch Stainless

Description Kerapatch stainless is a phosphate

bonded chrome-alumina plastic material. Compared to conventional phosphate bonded chrome-aluminas, Kerpatch stainless has appreciably lower shrinkage, which results in superior structural integrity. It is supplied in soft plastic consistency, ready to use, in plastic buckets.

Applications:

1. Induction furnace repairs.
2. Metal splash shields.
3. Abrasion resistant linings.
4. Sliding gate maintenance.
5. Long-life ladles and teapot ladles.
6. Runners and launders.
7. Water-cooled plate protection.

Composition: The aggregate is fused chrome alumina: a high purity synthetic alpha alumina polycrystalline aggregate with good temperature and chemical stability. The matrix is tabular alumina which has good bonding properties and thermal shock resistance. The phosphate binder develops high strength at 100ºC. A complex series of dehydration reactions follow, culminating in a very strong anhydrous bond at 400ºC. The ceramic bond develops from 1000ºC, and rapidly above 1200ºC. Before the phosphate becomes pyroplastic, the chrome-alumina bond is well developed. Consequently it has very high strength over the whole temperature range from 100ºC to 1800ºC.

Metal Protection: A sheet of expanded metal, heavy duty, such as Mentex 72, is bent and tacked onto the steel substrate such that it is positioned 10 to 15mm above the surface. The material is then pressed into this continuous anchorage and hammered tight. The thickness is typically 25mm. This system is used in the following applications:

1. The outsides of steel shells or structures which sometimes come into contact with pouring steel or ferroalloys. Eg.: Launder casings, especially upper edges. AOD hoods. Ladles with hoods. Bases of steel structures especially where silicon spillage is possible. Spincaster cover ends.
2. Where occasional metal flow is expected yet there is insufficient space to apply conventional refractories: Eg.: Tundish overflows. Continuous caster emergency launders. Teapot ladle spouts. Handheld purging lances.
3. Abrasion resistant linings where geometry is too complex for tiles. eg.: nozzles. 4. Abrasion resistant linings where the temperature fluctuation destroys tiles, Eg.: burner quarls, coke discharge chutes.

Where mechanical stresses are great, another system is used; Hexmetal reinforcing. The sheet of honeycomb metal is welded onto stainless steel plate and the keraplas packed into it. Each cell of the honeycomb is independently anchored, and the structure can withstand severe expansion and contraction and mechanical abuse. This system can be used on water-cooled copper panels etc.

Chemical analysis

Al2 O3 82.0%
Cr O 7.2%
Fe2 O3 1.7%
SiO2 4.0%
TiO2 0.02%
CaO 1.5%
MgO 0.2%
Na2 O 0.3%
K2 O 1.0%
P2 O5 3.4%
Total 101.5%


Packaging; 25kg plastic buckets, ready to intstall.

See also: Keramor chrome alumina mortars Refractory paint, green. Keraplas; Similar material with green chromic oxide. Alumina castables; Keratab and Rubycast. Injectable Rubyject.

Keraplas

Description: Keraplas is a range of phosphate bonded Chrome alumina plastic materials. Compared to conventional phosphate bonded chrome-aluminas, the Keraplas range has appreciably lower shrinkage, which results in superior structural integrity. Applications: 1. Induction furnace repairs 2. Metal splash shields 3. Abrasion resistant linings. 4. Sliding gate maintenance.

Grades: "Patching" A fine (95% - 1mm) Highly plastic material for patching by hand, metal splash protection and abrasion resistant linings. "Capping" A coarse but highly plastic material for induction furnace capping. (95% - 8mm). "Ramming" or "Ladle" A dryish yet plastic ramming material for ladles, pouring boxes and sliding gate nozzles. (95% - 8mm) Composition: The aggregate is tabular alumina: a high purity synthetic alpha alumina polycrystalline aggregate with good thermal shock resistance and excellent bonding properties. The matrix is alumina and chrome oxide, which sinter in a solid state reaction which results in ruby solid solution with negligible volume change. The binder is largely aluminium ortho-phosphate solution, which develops high strength at 100ºC. A complex series of dehydration reactions follow, culminating in a very strong anhydrous bond at 400ºC. The ceramic bond develops from 1000ºC, and rapidly above 1200ºC. Before the phosphate becomes pyroplastic, the chrome - alumina bond is well developed. Consequently Keraplas has very high strength over the whole temperature range from 200ºC to 1800ºC. Chrome oxide also imparts non-wetting properties.

Metal Protection: A sheet of expanded metal, heavy duty, such as Mentex 72, is bent and tacked onto the steel substrate such that it is positioned 10 to 15mm above the surface. Keraplas patching is then pressed into this continuous anchorage and hammered tight. The thickness is typically 25mm. This system is used in the following applications:

  1. The outsides of steel shells or structures which sometimes come into contact with pouring steel or ferroalloys. Eg.: Launder casings, especially upper edges. AOD hoods. Ladles with hoods. Bases of steel structures especially where silicon spillage is possible. Spincaster cover ends.
  2. Where occasional metal flow is expected yet there is insufficient space to apply conventional refractories: Eg.: Tundish overflows. Continuous caster emergency launders. Teapot ladle spouts. Handheld purging lances.
  3. Abrasion resistant linings where geometry is too complex for tiles. Eg.: nozzles.
  4. Abrasion resistant linings where the temperature fluctuation destroys tiles, Eg.: burner quarls, coke discharge chutes. See also: Keramor chrome alumina mortars Refractory paint, green.