Three calculators, two charts you can embed, five printable PDFs and four data files. Every figure comes from the guide each item links to, with the maker or standard it belongs to named next to it. The charts and data are CC BY 4.0: use them anywhere and credit GY Alumina with a link.
Calculators and selectors
- Tube weight calculator. Weight of an alumina tube or multi-bore insulator from OD, ID or bores, length and density, for one piece or a batch.
- Unit converter. Inch tube sizes to mm with our nearest catalog tubes, AWG wire to mm with the insulator bore it needs, and °C to °F.
- Protection tube material selector. Shortlists tube materials by thermocouple type, temperature, atmosphere and molten metal, with each source's rule.
Charts you can embed
- Thermocouple type × sheath material chart. Types K, N, J, E, T, R, S, B and C against C 799, C 610, C 530 and five metal tubes: the lower published limit and the rule for each pair. PNG; the embed code is under the chart.
- Maximum temperature by material. 28 published limits for alumina, mullite, quartz, zirconia, silicon carbide and sheath metals, each with its condition and whose figure it is. PNG; the embed code is under the chart.
Printable PDFs
- Alumina tube and crucible care. One A4 page for the lab wall: heating rates, insertion speeds, crucible handling and cleaning steps, maximum temperatures by grade.
- Thermocouple type × sheath chart. Two A4 pages: the chart, the rules behind each label, atmosphere notes and sources.
- Insulator bore-size chart. Two A4 pages: all 33 insulator sizes by bore, the largest wire each takes and the protection tube to compare.
- Thermocouple size reference. Three pages: protection tubes, stocked insulators and made-to-order sizes, with a quotation link per size.
- Crucible size reference. Seven A4 pages: 195 typical crucible, boat and lid sizes, with a quotation link per size.
Open data: CSV and JSON
Four tables from the guides as data files, rebuilt with the site so they always match the pages. Licence: CC BY 4.0. Credit line: “Source: GY Alumina (gyalumina.com), CC BY 4.0”. Source columns name whose figure each value is, exactly as in the guides.
GY Alumina standard sizes: alumina protection tubes, multi-bore insulators and furnace tubes
The 63 standard sizes on our factory's September 2026 size lists, in millimetres: 18 thermocouple protection tubes, 33 single-, twin- and four-bore insulators and 12 furnace tubes, with wall thickness computed as (OD − ID) ÷ 2, whether the size is usually in stock or made to order, the European closed-end series with the same OD × ID (a dimension match only) and the size's page. Lengths are cut to order.
CSV · JSON · 63 rows, 10 columns · From Thermocouple protection tube sizes
Thermocouple type × sheath material chart (K, N, J, E, T, R, S, B, C against ceramic and metal tubes)
Nine thermocouple types against eight sheath and protection-tube materials (C 799 alumina, C 610 mullite, C 530 porous, and five steels and alloys). Each row gives the type's published upper figures, the tube material's published upper figures by source, the lower of the two in °C, which part sets it, and the rule a named source (WIKA, JUMO, Rössel, Omega) gives for that pair. Every figure is the named source's, not a GY rating.
CSV · JSON · 72 rows, 9 columns · From Thermocouple types and temperature ranges
Alumina ceramic properties by purity: 96% and 99.5% (named suppliers' typical values)
Density (g/cm³ and kg/m³), thermal conductivity, thermal expansion, specific heat, Knoop hardness, flexural strength and dielectric strength for two dense alumina grades: CoorsTek AD-96 (96%) and CoorsTek AD-995 (99.5%), with each supplier's test conditions. Typical values for those suppliers' named materials, as published by them.
CSV · JSON · 2 rows, 13 columns · From Alumina density and properties by purity
Maximum temperature by material: alumina, mullite, quartz, zirconia, silicon carbide and sheath metals
28 published maximum temperatures (°C) for tube and sheath materials, each with its condition (continuous, in air, under vacuum, in inert gas) and whose figure it is: Morgan Haldenwanger, Precision Ceramics, the DIN 43724 table as reproduced by Morgan, the Brevier (DIN EN 60672), WIKA, Rössel, Nabertherm, Heraeus, MTI and Omega, plus the two GY Alumina material-table rows.
CSV · JSON · 28 rows, 5 columns · From Alumina maximum temperature
Buyer reference
- Buyer FAQ. Minimum order, lead time, stock sizes, samples, the ISO 9001 certificate, lab reports and packing.
- Quality documents. Our ISO 9001:2015 certificate and the Chinalco Testing chemical analysis of our alumina tube, as PDFs.
All guides are on the guides page. For a size that isn't in these tables, send the drawing with a quote request.