Low Pressure Table 150/110
The BELO low-pressure heating table with a patented heating system has been specially developed for the conservation of paintings.
All normal procedures such as flattening, relaxation, impregnation and fixation can be done on the table.
Due to the completely flat design of the work surface, it is possible to work in sections on very large paintings.
The electronic temperature control and the infinitely variable electronic control of low pressure are located in a separate housing. Easy handling is ensured by the clear arrangement of all operating elements. The power supply cable for the heating element of the table can be plugged in at the rear side of the control unit.
Table and control unit as well are mobile.
Working surface (Type 150/110):
|Surface of the table element:||1500 x 1100 mm|
|Power consumption heating element:||4 KW|
|Temperature:||infinetely variable from 20 – 70 °C|
|Temperature display:||digital (1 dezimal)|
|Malfunction signal:||in case of sensor brake and exceeding of nominal value the malfunction signal leads to automatic shutdown|
A rotation speed of the motor can be adjusted continuously from shutdown to maximum output by means of a potentiometer. The low pressure desired can be adjusted exactly. The mains plug of the low-pressure generator can be plugged in the corresponding socket on the rear side of the control unit. The socket has its own illuminated on/off switch (max. output 3000 W / 240V / 50 Hz).
|The control unit’s mains supply is ensured by means of a 5 m long cable plug.|
|Electric supply:||240/380 V (3P/N/PE, 32A)|
|Measurements:||width: 350 mm, height: 700 mm, depth: 300 mm|
The base of aluminium profile system:
• surface anodized, silver
• 4 lockable castors
• height custom-built
Technology / Heating Element
Our 10 years of experience with low-pressure tables has shown that the correct and limited use of warmth or heat is an important factor in the treatment of paintings on canvas. Thus it is important to assure a very steady and evenly distributed warming up and to apply precisely controlled and dosed heat to the object to achieve successful results.
BELO low-pressure tables are equipped with a heating element specially developed for the restoration of paintings. Our heating element is patented.
Based on our experience with conventional heating systems and their characteristics when used with low-pressure tables we have developed a completely new system. Other systems provide indirect heat by having a perforated work surface which is heated by a separate element that lies at a distance to the perforated work surface.
Our patented system involves the direct heating of the perforated work surface i.e. the perforated work surface is at the same time the heating element, and thus the heat is in direct contact with the object lying on the work surface. Heat is thus transmitted directly to the object.
Due to the low mass of the heating element, heating and cooling times are very short.
Figure 1: Temperature/time diagram
Measurements were taken on the uncovered surface of the table
Turning on of the heating at 20° C, heating up to 50° C in a time of 50 seconds.
immediate cooling down by switching off the heating after reaching a temperature of 50 °C
A: heating-up time
B: cooling down phase
Due to the low mass, it is possible to control the application of heat precisely during treatments. The time an object is subjected to heat during treatment can be limited to a minimum. Fast temperature changes, if necessary, are possible.
Overheating and excessive subjection to heat is avoided due to the fast response of the system. The temperature/time diagram shows the short times needed for the system to heat up 30°C or cool-down 30°C.
Furthermore, an even distribution of heat is achieved. As shown in the thermographic figure (see figure 2) the difference in temperature measured on a work surface 1500 x 1500 mm is only +/- 1.5°C. This constant and precise distribution of heat over a work surface is also achieved with larger work surfaces (up to 2 x 3 m) and within the whole temperature range.
The temperature is monitored by a heat sensor which is connected directly to the heating element and is electronically controlled. If the pre-selected temperature is exceeded or if there is a fault in the sensor, this will be registered by the sensor and the heating element will automatically switch off and the error will be shown on the digital display.
Figure 2: Computer thermographic figure
(measurements were taken on the uncovered surface of the table).
The coloured temperature ranges on the work surface
(1500 x 1500 mm, black surround) show the maximum of
42.5° C (white) and the minimum of 39.2° C (red).