Laboratory ovens, also known as laboratory furnaces, are utilized for sterilizing biohazardous waste, dissecting equipment, and media/reagents for aseptic experiments.

In addition, they are utilized for drying, heating, and testing environmental challenges such as temperature, light, and humidity variations. Laboratory ovens can be used in a variety of laboratories, such as a diagnostic lab to dry microscope slides, a research lab to evaluate the stability of products at different temperatures, or an industrial lab to sterilize a huge piece of equipment.

Types Of Laboratory Ovens

• Standard Digital Ovens – Constructed for the heating and drying process, with temperature control and safety features.
• Heavy-Duty Ovens — Commonly utilized in industrial applications for testing soils/aggregates and drying biological samples.
• High-Temperature Ovens – Ovens with temperatures over 500°C that are custom-built and insulation is added to the oven’s walls and doors.
• Vacuum Oven– The purpose of vacuum lab ovens is to eliminate moisture, gas, and other potentially volatile compounds while avoiding chemical reactions. The principal drying mechanism in a vacuum oven is the vacuum chamber itself. This reduces the boiling point of most substances and permits liquids to evaporate at lower temperatures.
• Gravity Convection Oven– Gravity convection ovens are designed for applications in which a fan or any other airflow would not interfere with the thermal process, such as the processing of lightweight materials or powders. They require less temperature uniformity than other types of laboratory ovens with mechanical convection. Gravity ovens provide a distinct natural air convection supply via perforated stainless steel shelves to achieve temperature consistency without the use of blowers.
• Forced Air Oven– Forced air ovens function by using a blower fan to circulate warm air around the oven chamber. Similar to a furnace, heated air goes through a duct system that distributes it evenly around the chamber.

Functions Of Ovens In A Laboratory

Annealing

The objective of annealing is to increase the ductility of a material (glass or steel) through heating and cooling. For this procedure, high-temperature ovens are utilized in a variety of metallurgy, medical device production, and material science applications. The healthcare industry uses stainless steel cleanroom ovens to anneal polymers onto syringes and catheters.

Drying

The most common purpose of laboratory ovens is drying, which removes moisture from materials, samples, etc. For conventional drying, several industries, including the environmental, clinical, and biological industries, utilize forced-air ovens, vacuum ovens, and gravity convection ovens. These ovens remove moisture from samples while reducing the boiling point of water in order to dry laboratory samples at lower temperatures.

Baking

The objective is to gradually heat samples without drying them out. This can be achieved most effectively by keeping the exhaust outlet closed. The other crucial aspect of this process is reducing heat loss, as the heated air retains the essential moisture. Due to this, ovens employ a unique kind of wrap-around insulation that leaves no seams or spaces for air to escape.

Die-bond Curing

Through a mix of drying and baking, laboratory ovens harden the chemical makeup of substances. This is a method for producing epoxies, adhesives, plastics, and rubbers for use in polymer research, nanotechnology, and the semiconductor industry. The improved adhesive strength is also extraordinarily beneficial for sticking components directly to circuitry, which is used in a variety of military, space, and medical applications.

Polyimide Baking

The polyimide is added to the oven in liquid form and then thermally baked to produce a thin film or layer for a variety of applications, such as stress buffer coating for redistribution layers, adhesion, chip bonding, and many more.

Curing

Curing is the process of hardening a substance’s chemical composition through the combined actions of drying and baking. This method is frequently employed in the production of epoxies, adhesives, plastics, and rubber in the polymer research, nanotechnology, and semiconductor sectors.

This procedure requires heating the product in the oven without dehumidifying it. In areas such as pharmaceutical, industrial, and material science, gravity convection ovens facilitate the baking process.

Standard and Unique Laboratory Oven Applications

Most laboratory ovens are typically used for heating and drying glassware or autoclaving lab supplies for sterilizing purposes. Commonly, laboratory ovens are used to assess the tensile strength, deformation, and resilience of a variety of manufactured items. Standard applications for laboratory ovens include the following testing and troubleshooting procedures:

• Testing of electronic equipment
• Burn-in test for early failure detection in produced integrated circuits
• Solder strength testing on printed circuit boards
• Accelerated simulations for measuring extended product use
• Curing advanced polymers to stimulate a chemical process and modify their chemical nature

In biological, forensic, and environmental labs, lab ovens are utilized in a specialized manner. Here are a few examples of how laboratory ovens are accelerating research in the natural sciences:

• Fingerprint development chambers in forensic laboratories are specifically designed vacuum ovens.
• Biological laboratories use gravity convection ovens to remove microbiological contamination from labware and vacuum ovens to affix substrates to the surface of filters and other media.
• Environmental laboratories dry specimens in laboratory ovens, weighing them before and after drying to measure the moisture content of the specimen. For these types of operations, convection and forced-air ovens are utilized.

Things To Consider Before Buying A Laboratory Oven

Temperature Variation

When matching a laboratory oven to a given application, maximum temperature ratings are of utmost importance. Obviously, you require an oven with maximum temperature equal to or somewhat higher than the highest temperature specified in your test methods. However, models with larger temperature ranges may not necessarily provide the optimal stability and homogeneity at lower temperatures. In addition, these ovens may utilize more expensive components and therefore can be more costly to operate.

Energy Prerequisites

Before making a purchase, you should determine the capacity and design of the electrical supply in your laboratory and the power requirements of the oven. Before installation, you may need to arrange for electrical improvements or alterations. During the initial phase of operation, the amperage draw of some ovens may exceed the given specifications. Where large chamber capacities or continuous operations are envisaged, and when lower uniformity can be accepted, gas-fired ovens may also be a possibility.

Chamber Size And Volume

Chamber volume and size are also significant aspects to consider when purchasing a laboratory oven. You must ensure that the chamber can fit the size and shape of your samples, as well as the number of samples that must be loaded at a given moment. If a chamber is too tiny, your workflow will be hindered, and if it is too large, lab space will be squandered. Consequently, be careful to choose an oven with the chamber capacity you want.

Materials 

Modern oven interiors and shelves are frequently made of stainless steel to withstand corrosion and deterioration. If your materials are not corrosive, then you can consider purchasing an oven with a stainless-steel interior. There are also double-walled ovens that provide excellent insulation between the oven chamber and outer cabinet, work more efficiently and consistently, and have a cooler exterior surface for increased safety.

Conclusion

Laboratory ovens serve a variety of purposes. While determining the purpose you want to use the oven primarily for, it is equally important to look for the appropriate features and properties that it possesses.

 References:

https://www.coleparmer.com/blog/2014/09/12/laboratory-ovens-whats-the-difference/

https://www.sonicsupply.com/laboratory-ovens/?v=c86ee0d9d7ed

https://www.despatch.com/blog/what-are-laboratory-ovens-used-for/

https://www.mynewlab.com/blog/what-are-ovens-used-for-in-a-laboratory/

https://www.laboratory-equipment.com/blog/applications-for-laboratory-ovens-across-the-sciences/

https://www.globalgilson.com/blog/choosing-the-right-lab-oven