Vertical Tube Furnace

What is the Vertical Tube Furnace?

A vertical tube furnace holds the work tube upright so samples hang or drop through a controlled hot zone. It is chosen for drop-tube experiments, quenching studies and suspension processing under gas or vacuum.

Overview

The vertical furnace mounts the work tube upright, so a sample can be suspended in the hot zone on a wire or rod and then lowered or dropped into a quenching medium below. This suits drop-tube reactors, rapid quenching, thermal analysis by weight change and processing of suspended particles or fibers. Tube diameters run 30 to 100 mm, heated lengths 300 to 800 mm, and temperature reaches 1200 to 1600 C depending on the tube and elements. End caps carry gas inlets and outlets, and the assembly may sit on a stand with a quench bath below. Feed-throughs allow thermocouples or suspension wires to enter the hot zone. It is used in materials research where rapid heating or cooling reveals phase behavior.

How does it work?

A tube furnace surrounds a cylindrical work tube with heating elements embedded in ceramic fiber or refractory, so the sample is heated inside a controlled environment separate from the elements. The tube, usually quartz, alumina or a high-temperature alloy, passes through one or more heating zones. Gas enters one end, flows over the sample and exits the other, or a pump pulls vacuum for anaerobic work. Thermocouples measure each zone, and a PID or SCR controller holds setpoints or programmed profiles. Split designs open to place the tube without threading it, while multi-zone designs create a controlled temperature gradient. End seals, flanges and gas manifolds keep the atmosphere clean and safe, and exhaust may pass through a scrubber or bubbler.

What are the key features?

• Upright work tube with sample suspension
• Drop or lower into a quench bath below
• Tube diameters of 30 to 100 mm
• Heated lengths of 300 to 800 mm
• End caps with gas inlet and outlet
• Feed-through for thermocouple or suspension wire

What are the technical specifications?

A typical vertical tube furnace configuration offers work tube diameter of 30–100 mm, heated length of 300–800 mm, temperature range of RT to 1600 C, orientation of Vertical, quench bath of Optional, below the tube and tube material of Quartz or alumina. Values are indicative of the product class; the exact figures for each configuration are confirmed on the quotation and the calibration documents supplied with the instrument.

Which applications is it used for?

The Vertical Tube Furnace is used in drop-tube reaction experiments, rapid quenching studies, suspension and fiber processing, thermogravimetric-style tests and phase behavior research. Across the wider Tube Furnaces class, laboratories also deploy it for controlled-atmosphere calcination, chemical vapor deposition and catalyst reduction and activation.

Which standards and certifications apply?

Relevant standards and methods include IEC 61010-1, IEC 61010-2-010, IEC 60519-1, DIN 17052-1 and ISO 9001. Certification candidates for this model are CE, ISO 9001 manufacturing and RoHS; each is to be confirmed for the specific configuration before shipment, and certificates are supplied only where they have been issued.

Install with clearance for the hot tube ends and route exhaust gases to a safe vent, using a scrubber or bubbler for toxic or corrosive species. Use only tubes rated for the temperature and atmosphere, and never exceed the manufacturer limit, since quartz softens and alumina can crack under thermal shock. Support long tubes and avoid mechanical stress at the seals. Purge the tube before heating when air must be excluded, and check for leaks after each assembly. Calibrate the control thermocouple and profile the hot zone, and replace tubes showing cracks, devitrification or sag before failure.

How do I select the right Vertical Tube Furnace?

Select the vertical furnace when the sample must be dropped or lowered through the hot zone, or quenched rapidly from temperature. Horizontal tube furnaces suit gas-flow calcination. In the RFQ, specify tube diameter, heated length, top temperature, quench arrangement, atmosphere and feed-through needs.

How does it compare with other Tube Furnaces variants?

Choose a tube furnace when the process needs gas flow, vacuum or a sealed environment, or when the sample must be a powder in a boat rather than a crucible in a box. Set the maximum temperature with margin above the working setpoint, and select the tube material accordingly: quartz to about 1100 C, alumina to 1600 to 1700 C, and alloys for specific atmospheres. Match the tube diameter to the sample boat, and pick one, three or five zones depending on whether a gradient or uniform hot zone is needed. Decide between solid and split designs for handling. Specify gas connections, end seals, flow meters and safety features for flammable or toxic gases.