Definition

Noun: A pyrometric cone is a small, slender, three-sided pyramid made from carefully formulated ceramic materials. It is designed to bend and melt at specific, known temperatures when heated in a kiln. It serves as a visual indicator to monitor the progress of a firing, measuring the combined effects of temperature and time (often referred to as "heat work").

Usage

Pyrometric cones are used primarily in ceramics and pottery to gauge the maturity of clay and glazes inside a kiln. They are placed in the kiln where they can be observed through a peephole. As the kiln heats, the cone softens and bends. The specific angle of bend indicates the amount of heat work achieved.

Examples

• Basic Usage:
  • "To ensure the glaze matures correctly, the potter placed a pyrometric cone in the sitter of the kiln."
  • "The pyrometric cone number 6 bent over, signaling that the firing was complete."
• Technical Context:
  • "The technician compared the deformation of the pyrometric cone to the kiln's digital thermometer reading."
  • "A series of pyrometric cones (cones 5, 6, and 7) were used to monitor the temperature gradient within the kiln."

Advanced Usage

• "Cone bending" or "Cone deformation": Refers to the physical act of the cone softening and bending, which is the key event being observed.
  • "The final cone bending confirmed the successful bisque firing."
• "Cone pack": A small set of multiple cones placed together to provide a more detailed profile of the firing.
  • "She prepared a cone pack with a guide cone, a guard cone, and the target cone."

Variants and Related Words

• Orton cone: A common brand name for pyrometric cones, often used synonymously in the ceramics community.
• Witness cone: Another term for a pyrometric cone, emphasizing its role as a witness to the firing conditions.
• Cone equivalent (CE): A term used to describe the temperature rating of a kiln firing in relation to the pyrometric cone system (e.g., "Cone 6").
• Pyrometer (n): A broader category of instruments for measuring high temperatures, which includes pyrometric cones as one type.

Synonyms

• Firing cone
• Kiln cone

Related Concepts

• Heat work: The combined effect of temperature and time on ceramic materials, which is what pyrometric cones actually measure, not temperature alone.
• Cone chart: A reference table that lists the nominal bending temperatures for each cone number under a standard heating rate.

Noun

1. a pyrometer consisting of a series of cones that melt at different temperatures