Key points to improve the temperature uniformity of the blast oven:
Electrothermal blast drying oven (hereinafter referred to as drying oven) is a kind of widely used laboratory instrument and production process
equipment. Shanghai Huanjing Test Equipment Factory has produced this type of products for many years, but most of the highest temperatures are at 300 degrees.
Below, its technical indicators are better. In recent years, there have been more and more orders for drying ovens at 400 degrees.
The drying oven below 400 degrees, although its "temperature uniformity" indicator can meet the standard requirements, but always compare
Critical, a little carelessness may exceed the standard. Recently we have taken a series of drying ovens above 400 degrees.
The improvement measures have greatly improved the “temperature uniformityâ€. Industry standards dictate the uniform temperature of the product
The sex index is plus or minus 2.5% of the maximum temperature, and after the improvement, this index basically remains around plus or minus 1.5, making this
One indicator has been greatly improved. We have mainly taken the following measures:
1. Improve the air distribution structure of the drying box:
The quality of the “temperature uniformity†indicator of the oven depends on the structure of the airflow. Drying box is usually a single wind
The air flow in the structure is mainly from the centrifugal fan system. In this structure, centrifuge several machines
The design of the shell and the design of the wind deflector are the key to determining the index. So we first strictly followed the Archimedean spiral
The principle redesigned the volute. The air flow from the outlet of the volute can be evenly blown through the heater to ensure a uniform air supply.
In addition, we have made corresponding improvements to the air outlet and return air outlet of the air deflector and increased the wind at the air outlet as much as possible.
Volume, while increasing the wind pressure and wind speed at the outlet. The air flow can be circulated evenly in the working chamber.
2, determine the heater's best location:
Whether the heat emitted by the heater can be evenly brought into the working chamber by air flow is to ensure the temperature of the work chamber
The key to uniformity. Therefore, it is very important to determine the best position of the heater. After repeated trials, we finally
The ideal position of the heater was determined so that the technical indicators in the box were effectively improved.
3, improve the sample shelf:
Single air flow structure The gas flow must pass through the sample shelf. The general drying box has at least two shelves. Special requirements
Even more. In the past, the shelves were punched out of sheets and demolded. But to ensure its strength, shelves
The aperture density cannot be too large, which results in excessive resistance to the circulation of the air flow and affects the temperature uniformity from the surface. I
We changed the shelf into a steel wire structure to better solve this problem.
4, improve the door locking device:
In the drying oven of 400 degrees or more, the material is deformed by heat after being heated. The door of the past high temperature drying oven is mining
Single-point locking, but in the high temperature above 400 degrees, after the door is deformed, the door and the box are closed, causing the door to close
Leakage heat, the temperature inside the working chamber of the box against the outside of the door is low, affecting the uniformity of the box. We changed the door to double
Locked so that this problem has been solved. Through the "temperature uniformity" indicator of the drying oven for 400 degrees and above
We have gained a lot of inspiration from improvement and accumulated some experience. I believe this for our future drying box design
Modifications will have a certain effect.