Vacuum table 300/200

The BELO-The vacuum table, equipped with patented heat generation, is specifically designed for the field of painting restoration.

All standard procedures such as leveling, consolidation, impregnation and tack-setting can be carried out on the table.

The raised, step-free work surface makes it possible to work on even large-format paintings in sections.

The electronic temperature control and the stepless electronic vacuum control are housed in a separate casing.

The clear arrangement of the controls makes handling easier.

The power supply cable for the heating element between the control unit and the table element can be plugged into the back of the housing.

The table and control unit are mobile.

Photo: 3rd MA student group vacuum table workshop 2020 at the Hildesheim University of Applied Sciences.

work surface (Type 300/200):

Temperature controller:

Vacuum control:
The motor speed is continuously adjustable from standstill to maximum power via a potentiometer. This allows for precise setting of the desired pressure. The vacuum generator's power plug is inserted directly into the designated socket on the back of the control unit. The socket has its own illuminated on/off switch (max. power 3000 W / 240 V / 50 Hz).

Base:
Base frame made of aluminum system profile:
• Natural anodized surface
• 4 lockable swivel casters
• Height as specified by you

The technology / The heating element

Our over 10 years of experience with vacuum tables has shown that the application of heat is a crucial factor in the treatment of canvas paintings. Therefore, it is essential to ensure an extremely uniform, precisely controllable, and adjustable heat application to the artwork in order to enable targeted treatment.

BELO vacuum tables are equipped with a heating element specifically developed and patented for painting restoration.
Based on experience with conventional heating systems and their characteristic properties when used with vacuum tables, a completely new system was designed. This system differs fundamentally from indirect heating systems, where a separate heating element heats a perforated surface.

Through the patented process of directly heating the perforated surface, meaning the perforated surface itself acts as the heating element, heat is generated in the immediate vicinity of the object. The heat is then transferred directly to the object via the shortest possible path.

Unusually short response times for heating and cooling are achieved due to the low mass of the heating element.

Figure 1: Temperature/time diagram
Measurement without covering the directly heated surface

The heater switches on at 20°C and heats up to 50°C within approximately 50 seconds.
A: Heating phase – Immediate temperature drop due to switching off the heating after reaching a temperature of 50°C.
B: Cooling phase

Due to the short response times, heat can be used in a very targeted, controllable and short-term manner for treatment purposes. Fast

Temperature changes depending on the requirements of the object being processed are possible.

Overheating and overshoot are avoided by the system's immediate response. The temperature-time diagram illustrates these short heating and cooling times at a temperature difference of 30°C and demonstrates the low inertia of the heating system.See Fig. 1)

Furthermore, an extremely uniform heating of the perforated surface is achieved.
As the computer thermographic image (see Fig. 2) illustrates, the measured temperature difference across a working area of ​​1500 x 1500 mm is only +/- 1,5°C. This uniformity of heat distribution is maintained even with other dimensions up to 2 x 3 m working area and across the entire temperature range.

The temperature is measured by a temperature sensor directly connected to the heating element and regulated by an electronic control unit. Sensor failure and exceeding a preset limit value are detected by the control unit and result in the heating element being switched off while simultaneously displaying the error.

Figure 2: Computer thermographic image
(Measurement with the heating element uncovered)
The temperature ranges observed in the work area (1500 x 1500 mm, shown here in black outline) and represented in color gradations show a maximum of 42,5°C (white fields) and a minimum of 39,2°C (red fields).