Tube Furnace Application Options

Carbolite Inconel Retort

Gas and Air Flow Options

Gas flow meters
Carbolite's gas flow meters are designed to work with Argon, Carbon Dioxide, Hydrogen or Nitrogen.  The flow meters have a scale length of 100 mm (3‰ accuracy) with needle valve and can be fitted to a worktube and a gas inlet. A mounting bracket is included.

Atmosphere Control System
An atmosphere control system is recommended for greater safety and convenience in control when hydrogen gas is required for processing. The control system is suitable for use with a box furnace and atmosphere retort or a gas tight tube installed in tube furnaces.

Temperature Measurement Options

Temperature Indicator
A digital temperature indicator can be built into the furnace's control panel and wired to a panel mounted thermocouple socket.  The display is also available in a separate, stand alone cabinet, so it can be used as a portable temperature checker.

Thermocouple calibration port
An additional thermocouple ceramic sheath is installed adjacent to the control thermocouple.  This additional port allows for the insertion of a second reference thermocouple for checking or calibration of the existing controller/thermocouple system

Additional Thermocouple
An additional thermocouple, similar to the control thermocouple, is built into the furnace and connected to a thermocouple socket. This thermocouple socket is mounted in the furnace's control panel. Typically used by the customer for connection to a recorder or other temperature measurement device.

Cascade Control

Control System Options

Cascade Control
A standard control system senses the temperature close to the heating elements, while the temperature of the load is usually at a temperature slightly lower then this measurement.  In an effort to overcome this fact while brining the furnace up to temperature, a second controller can be added.  With the addition of this second controller, a faster warm up is achieved by boosting the element temperature when the load is cold and by reducing it as the load approaches the desired temperature.

Chart and Data Acquisition Recorders
Carbolite can offer both Chart and Data Acquisition Recorders in single or multiple channels.  Assorted optional features are available with all recorders including software to allow a user to review data off-line or via a remote computer.  Recorders can be provided with calibration certificates.

Digital Communications
Digital communications from the furnaces controller can be achieved through an RS232, RS485 or RS485/RS422 converter.  Data transmission or data logging can be accomplished via our iTools software package.

Additional Tube Furnace Options

Gas Tight End Seals
Gas tight end seals can be used to create a gas tight seal on your process tube.  These seals can be equipped with a 6 mm hose connection that can be used as a gas inlet or outlet.  Gas tight end seals are appropriate for tube diameters of 2" or larger. Standard end seals are suitable for vacuums to 10-3 mbar.  For higher vacuums to 10-5 mbar, a double flange end seal design is available.

Insulating Plugs and Radiation Shields
Insulating plugs and radiation shields are often used in an effort to minimize the heat losses from your process tube while improving the temperature uniformity within your process tube.

  • Type C insulating plugs are designed for applications when processing will be done under air - suitable for use with tubes of 1.5" ID and larger.
  • Type D insulating plugs are normally used in conjunction with gas tight end seals when processing is carried out under an atmosphere - suitable for use with tubes of 2" ID and larger.
  • Radiation shields are normally used in conjunction with gas tight end seals when processing is carried out under atmosphere and ceramic fiber plugs are unsuitable.  Suitable for use with tubes of 2" ID and larger.

Worktubes

A Ceramic or inconel worktube fitted inside a Carbolite tube furnace allows the use of a gas atmosphere.  Carbolite proudly provides a wide variety of worktubes to support your heating application including:

  • Sillimanite - porous, good thermal shock resistance (max temperature 1500°C)
  • Impervious aluminous porcelain (IAP) - impervious (max temperature 1400°C)
  • Mullite - impervious and resistant to flux, sulphurous & carbonaceous atmosphere (max temperature 1500°C)
  • Recrystallized alumina (RCA) - impervious and highly resistant to chemical attack (99.7% Al2O3) (max temperature 1800°C)
  • Advanced powder metallurgy (APM) - impervious FeCrAl alloy tube, not susceptible to thermal shock (max temperature 1300°C) these tubes are unsuitable for use inside (MTF & CTF) wire wound tube furnaces