Shaped Refractories / Andalusite Bricks

A-55 Andalusite Bricks

A-55 is the 55-58% Al₂O₃ grade in Shanker Agencies’ andalusite bricks range, rated for continuous service to 1550°C. The nearest export designation is SK 36.

Also known asA-5555% aluminaSK 36

Also meets SK 30, SK 32, SK 34, SK 35 requirements. Those are lower duties, so a lighter grade may be the more economical choice.

A-55 grade andalusite bricks supplied by Shanker Agencies
Grade
A-55
Al₂O₃ content
55-58%
Max service temperature
1550°C
Cold crushing strength
55 MPa
Refractoriness (PCE)
SK 35

A-55 technical specification

Typical values for A-55 andalusite bricks. Test methods vary by property and product family, so confirm the applicable standard against the manufacturer datasheet before specifying.

PropertyA-55
Al₂O₃ content55-58%
Apparent porosity15-18%
Cold crushing strength55 MPa
Refractoriness (PCE)SK 35
Max service temperature1550°C

Grade designations and equivalents

How A-55 is referenced across Indian and export naming conventions.

SAPL grade codeA-55
Indian trade names55% alumina
Export SK equivalentNearest SK step, minimum 55% Al₂O₃SK 36
Also meetsExceeds these requirements, a lower grade may suit those dutiesSK 30, SK 32, SK 34, SK 35
Alumina content55-58% Al₂O₃
Measured refractoriness (PCE)This brick’s own cone value, not its SK trade gradeSK 35
Max service temperature1550°C

Reading an SK code correctly. SK (Seger Kegel) is a cone designation, and each step carries an accepted minimum Al₂O₃ content in trade practice. The dependable way to match an SK enquiry to a grade is that minimum alumina figure, which is how the equivalence above is derived. Note that a brick’s measured PCE and its SK trade grade are two different numbers and will not always agree. Suppliers also differ at the margins, most often around SK 34. When comparing offers, check Al₂O₃ and PCE together rather than the SK code alone.

SK series to andalusite bricks reference

Standard SK steps with the SAPL grade that meets or exceeds each one. Grades are matched at or above the minimum alumina for the step, so an SK enquiry is never answered with an under-spec material.

SK gradeMin Al₂O₃Cone equivalentSAPL andalusite bricks
SK 3030% Al₂O₃1670°CA-55
SK 3232% Al₂O₃1710°CA-55
SK 3438% Al₂O₃1750°CA-55
SK 3545% Al₂O₃1770°CA-55
SK 3655% Al₂O₃1790°CA-55this grade
SK 3765% Al₂O₃1820°CEnquire
SK 3870% Al₂O₃1850°CEnquire
SK 4082% Al₂O₃1920°CEnquire

Where A-55 is used

Blast furnace hot-blast stoves
Reheating furnace hearth & walls
Ceramic & sanitaryware kilns
Cement plant preheater & riser ducts
Steel ladle safety lining
Petrochemical heater linings

Full andalusite bricks range

Compare A-55 against every grade SAPL stocks in this family.

GradeAl₂O₃ contentApparent porosityCold crushing strengthRefractoriness (PCE)Max service temperature
A-5555-58%15-18%55 MPaSK 351550°C
A-6060-63%14-17%70 MPaSK 361600°C

Installation notes

  1. 1Joint with andalusite or high-alumina mortar of matching grade
  2. 2Maintain 2–3 mm joints and standard expansion allowance
  3. 3Controlled dry-out per OEM curve to allow in-situ mullitisation
  4. 4Excellent choice where bricks must hold dimension through repeated thermal cycles

Disclaimer: values are typical and compiled by Shanker Agencies Pvt. Ltd. from standard industry data and published manufacturer specifications. They are indicative, not a guarantee. Confirm the exact grade datasheet before specifying. For a certified datasheet or quotation, contact info@shankeragencies.com or +91 98999 57888.