While the term muffle furnace or retort furnace is still in use today it doesn t really mean the same thing as it did in the early 20 th century when wood and coal were the primary ways to heat a furnace.
What is a retort furnace.
The airtight vessel where the material is processed is the retort.
A muffle furnace or muffle oven sometimes retort furnace in historical usage is a furnace in which the subject material is isolated from the fuel and all of the products of combustion including gases and flying ash.
This action of tumbling provides uniform heating and process gas distribution for very small and densely packed workloads.
The retort furnaces of the nr and nra product line are perfectly suited for debinding under non flammable protective gases or for pyrolysis processes.
Muffle furnace is a term made by the furnace manufacturers.
A muffle furnace s primary attribute is that it has separate combustion and heating chambers.
The retort is a gas sealed chamber that the material to be heated is.
Retort furnaces allow accurate and efficient control of the work space argon or hydrogen atmosphere and provide low atmosphere usage due to the closed nature of the system.
Retort furnaces have a sealed vessel that is placed over or around the product and separates the product and process space from the system insulation and heat source.
High temperature muffle retort furnaces.
Retorts were widely used by alchemists and images of retorts appear in many drawings and sketches of their laboratories.
A pump evacuates the retort and the process runs either under vacuum or at a specific negative or positive pressure once the initial vacuum level is reached.
Before the advent of modern condensers retorts were used by many prominent chemists such as antoine lavoisier and jöns berzelius.
A muffle furnace refers to the insulation and separation of the heating elements from the contents of the retort.
Exhaust gases are burned in an exhaust torch.
The retort furnaces of the nr and nra product line are perfectly suited for debinding under non flammable protective gases or for pyrolysis processes.
The defining characteristic of a muffle furnace is that it separates the object to be heated from all by products of combustion from the heat source.
The advantages of using a retort include the fact that the furnace surrounding the retort can be gas fired or electrically heated and that the retort can be rapidly pumped down.
And the term retort comes from the chemical industry.
The furnace style is a revolving retort which is a horizontally oriented drum with internal flights that while rotating it tumbles and conveys the load from one end to the other.
After the development of high temperature heating elements and widespread electrification in developed countries new muffle furnaces quickly moved to electric designs.
With modern electrical furnaces this means heat is applied to a chamber through induction or convection by a high temperature heating coil inside an insulated material.
The idb version of the retort furnaces implements a safety concept by controlled purging the furnace chamber with a protective gas.
Difference between retort and muffle furnaces.
