choosing and installing monolithic refractories ‘boy’ ilano iii (pme) - president & gm 360...

CHOOSING AND INSTALLING MONOLITHIC REFRACTORIES

‘BOY’ ILANO III (PME) - President & GM

360 Degrees Marketing and Services Industry, Inc.

(Engineers and Consultants, Refractory Specialists, Manufacturer’s Representative)

Engineers and Consultants Refractory Specialists

Manufacturer’s Representative

In order to design a

lining that will work,

we need to understand

the reasons why linings fail.

Factors that cause linings to fail include:

• Material selection• Thermal design• Mechanical design• Mechanical / Chemical

damage• Anchoring failure• Installation• Commissioning



THE FOUR (4) MAJOR INSTALLATION GRADES OF MONOLITHIC

REFRACTORIES

CASTING Grades

GUNNING Grades

RAMMING Grades

PATCHING (Trowelling) GradesEngineers and Consultants Refractory Specialists


Relative Tendencies of the SiO2 – Al2O3 Castable

RefractoriesTendency 1 - Higher Alumina Castables tend to have higher Service Temperatures.

Tendency 2 - Higher Alumina Castables tend to have higher Densities (Net Quantity of Dry Material Required for Placement, kg/m³), hence, higher material consumptions.

Tendency 3 - Higher Density Castables tend to have higher Compressive Strengths but lower Thermal Shock Resistance.

Tendency 4 - High Alumina Castables tend to have lesser resistance to Alkali Attack. Conversely, lower Alumina Castables are more resistant to Alkali Attack. Tendency 5 - Mullite is the only stable compound in the binary system of the silica-alumina. It has excellent high temperature properties with improved thermal shock and thermal stress resistance owing to its low thermal expansion, good mechanical strength and interlocking grain structure.

Generality 5 – Silicon Carbide is a high thermal conductivity material coupled with low thermal expansion and high strength giving it an exceptional thermal shock resistant qualities. It is not attacked by any acids or alkalis or molten salts up to 800°C.



Silicon Carbide is a high thermal conductivity material coupled with low thermal expansion and high strength giving it an exceptional thermal shock resistant qualities. It is not attacked by any acids or alkalis or molten salts up to 800°C.

SiC O2

O2

O2

O2O2

O2

O2O2

SiC

SiC O2

O2

SiO2

CO2

Al2O3

Al2O3

Al2O3

Al2O3 (gas)

(gas)

Very Oxidizing conditions and High Temperature

O2

O2SiC

SiC

SiC SiC

SiC O2

O2

O2

O2O2

O2

O2 O2

SiC O2O2

Al2O3

Al2O3

Al2O3

Al2O3

SiC

More Oxidizing conditions and Higher Temperature

SiO2 SiO2

CO2 CO2 Al2O3 Al2O3

Al2O3 Al2O3



COMPARISON – 1: ECONOMICS BETWEEN HASLE REFRACTORY CASTABLES VS. SOME TYPICAL EQUIVALENTS

HASLE Caldery's Caldery's Caldery's

D39A Gibram SR ETaicast L60 A

SRThercoflow

5560

PHYSICAL DATA:Maximum Serice Temperature (deg.C) 1,500 1,700 1,550 1,500Density (Net Quantity of Dry Material Required for Placement) (kgs./m3) 2,200 3,050 2,500 2,600MODULUS OF RUPTURE (Mpa)

after heating to 110deg.C

16500deg.C 16

1,000deg.C 181,500deg.C 16

COLD CRUSHING STRENGTH (Mpa)

after drying to 110deg.C 115 62 37 50500deg.C 120

1,000deg.C 1301,500deg.C 150 135 66 71

(@1450deg.CTHERMAL CONDUCTIVITY:

400deg.C W/mK 1.16800deg.C W/mK 1.28 1.15 6.3

(@1450deg.C1,200deg.C W/mK 1.51 2.40ALKALI TEST (scale 0 - 10 mm.) 0RESISTANCE TO ABRASION (Abrasion Loss by Grinding, g/cm3) at 20deg.C 0.30RESISTANCE TO ABRASION (Erosion Loss by Blast Abrasion @ 90deg. angle, cm3) 1,000deg.C 4.40RESISTANCE TO THERMAL SHOCK (Retained Strength) Good

CHEMICAL ANALYSIS (%)Al2O3 39 87.4 58.4 26.2

SiO3 56 7.6 36.8Fe2O3 1.4 0.5 0.8 0.2

CaO 1.6 1.2 1.3 1.5SiC 0 0 0 59

P a r t i c u l a r s

Cost Comparisons and its Impacts

Assumed Prices: P85/kg. & P85/kg.Given Densities:2,200kgs./m33,050kgs./m3

Viewed from the 2nd Dimension of Cost:D39A = P85*2,200 = P187,000/m3Gibram = P85*3,050 = P259,250/m3

(39% more expensive)

Gibram + Thercoflow 5560= P85/kg. + P125/kg. (assumed)= P105/kg., average price

Average Density = 3,050 + 2,600 = 2,825kgs./m3

Composite Price = P105* 2,825 = P296,625/m3


Taicast L60A + Thercoflow 5560 = P75/kg. + P125/kg. (assumed) =P100/kg., average priceAverage Density = 2,500 + 2,600 = 2,550kgs./m3Composite Price=P100*2,550kgs./m3 = P255,000/m3


(Based on ALKALI ATTACK Resistance Requirements)



The Effects of castable Temperatures.

WATER ADDITION = 5.2%

SO CASTABLE MATERIAL = 94.8%

TOTAL MASS PER MIX = 100.0%

SO, COOL YOUR CASTABLES MORE,

THAN CONCENTRATING

ON COOLING YOUR WATER.





The IMPLIMENTATION of Tactical Plans – The Effects of castable Temperatures.



The Dangers of Water Control through plastic containers.






1.5liters Mineral Water plastic container filled-up 100% weighed exactly 1.5kgs. in calibrated weighing scale.




1.5liters Mineral Water plastic container filled-up partially to simulate the most likely section where it will be cut to facilitate easy scoping of water during water addition weighed only around 1.3kgs. in calibrated weighing scale. This translates to approx. 13.33% loss in water addition which will find its effects to the castable mix during casting installations.

The Effects of Adding More Water Than Necessary.



The Critical Pre-Shutdown Activities

25 50 75 100 125 150 175 200 225 250 275 3001BAG 2BAGS 3BAGS 4BAGS 5BAGS 6BAGS 7BAGS 8BAGS 9BAGS 10BAGS 11BAGS 12BAGS

D39A%5.0 1.25 2.50 3.75 5.00 6.25 7.50 8.75 10.00 11.25 12.50 13.75 15.005.5 1.38 2.75 4.13 5.50 6.88 8.25 9.63 11.00 12.38 13.75 0.50 16.506.0 1.50 3.00 4.50 6.00 7.50 9.00 10.50 12.00 13.50 15.00 16.50 18.00


D52A%4.0 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 11.00 12.004.6 1.15 2.30 3.45 4.60 5.75 6.90 8.05 9.20 10.35 11.50 0.60 13.805.2 1.30 2.60 3.90 5.20 6.50 7.80 9.10 10.40 11.70 13.00 14.30 15.60


D59A%4.0 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 11.00 12.004.4 1.10 2.20 3.30 4.40 5.50 6.60 7.70 8.80 9.90 11.00 0.63 13.204.8 1.20 2.40 3.60 4.80 6.00 7.20 8.40 9.60 10.80 12.00 13.20 14.40

WATER ADDITION GUIDELINES FOR HASLE LCC MONOLITHIC MATERIALS

KILOGRAMS TO BE MIXED

KILOGRAMS TO BE MIXED

KILOGRAMS TO BE MIXEDParticulars

Particulars

Particulars

Do Not Assume. If In doubt, Ask.



The IMPLIMENTATION of Tactical Plans – The recommended water addition manner.



Beating the castable ’Setting Times’.

Castable SETTING TIMES come in 2 stages, i.e. INITIAL Setting Time, and FINAL Setting Time.Generally, INITIAL Setting Time starts between 20-60minutes. FINAL Setting Time is between 60-90minutes.If the area to be casted is, say, 1.5meters x 1.5meters x 0.30meters, then volume to be casted = 0.675cubic meter/panel.If Nett Material Reqt. Per Cubic Meter of dry castable is = 2,800kgs./cubic meter, then total quantity of dry castable required = 1,890kgs. (0.675m3/panel * 2,800kgs./m3 = 1,890kgs./panel). If capacity of mixer is, say, 350kgs./mixture, and mixing cycle time is, say, 10minutes then Mixer Discharge Rate (or, Output) = 2,100kgs./hr. (60mins. per hr. / 10mins. per mix = 6 mixes /hr. * 350kgs./mix = 2,100kgs./hr.)Therefore, it will only take approx. 54mins. to finish the whole panel (i.e. 1,890kgs. per panel / 2,100kgs. per hr. = 0.9hr. per panel * 60mins. per hr. = 54minutes/panel.)



If capacity of mixer is, say, 75kgs./mixture, and mixing cycle time is, say, 10minutes then Mixer Discharge Rate (or, Output) = 450kgs./hr. (60mins. per hr. / 10mins. per mix = 6 mixes /hr. * 75kgs./mix = 450kgs./hr.)

Therefore, it will only take approx. 54mins. to finish the whole panel (i.e. 1,890kgs. per panel / 450kgs. per hr. = 4.2hr. per panel * 60mins. per hr. = 252minutes/panel). . . which is way above the FINAL Setting Time of a typical Dense Low Cement Castable Refractory.

Beating beaten by the castable ’Setting Times’.

Beating the castable ’Setting Time’ by use of multiple and/or rightly-sized Castable Mixers.



Choosing the Right Metallic Anchor Supports

. Metallic anchoring material grades must be properly specified since different metals oxidize differently under different temperature levels. If not properly selected, metallic anchors ‘rusts’ and the process is expansive, meaning it will ‘grow’ and inflict unnecessary stresses to the refractory linings. Such is the start of cracking which could lead to refractory spalling. (LOCATION – FORTUNE CEMENT CORP., Phils. – Cyclone Roof)

.

Actual footages of metallic anchors used in Line 2 Cooler Bull Nose Section. Indonesia. April 2011.

.

Anchor Diameter, mm. 6.0 8.0 10.0 13.0Lining Thickness, mm.

75 or less 50 - 10075 - 100 100 - 200100 - 200 200 - 300

200 or more 300 - 350

MAXIMUM ANCHOR SPACINGS, mm.

Conditions determining furnace lining support spacing

1. Support material2. Hot face refractory

3. Thickness of hot face lining4. Face operating temperature

5. Lining position6. Lining shape7. Lining size

8. Method of installation9. Mechanical movement of face if any

.

Be sure to specify that only welding rods with proper grade markings and color-codings be used to weld metal to metal. Same welding rod specs & manufacturer, but one has

proper markings (rod grade and color coding) whilst the other has non.

Improper welding rod usages to welding metal to metal can result to poor welding quality and, premature refractory lining failures.

.

Guide to Welding Electrode Compatibilities

choosing and installing monolithic refractories ‘boy’ ilano iii (pme) - president & gm 360...

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