Electrical heating cartridge

In a hot runner mold, the runner is contained in a manifold which has electrical heating cartridges. The heated runner keeps the GRTP in a fluid condition (Fig. 7-4). 

SPE cartridge column Mega Bond Elut Cig, lO-g/60-mL (Varian). The SPE cartridge column is rinsed with 100 mL of methanol and 100 mL of distilled water Rotary vacuum evaporator, 40 °C bath temperature Water-bath, electrically heated, temperature 80 °C Mechanical shaker (universal shaker)... 

A combined evaporator and methanol reformer was developed by Park et al. [124] to power a 5 W fuel cell. However, the device was still electrically heated by heating cartridges. Both the evaporator and the reformer channels, which were identical in size, were prepared on metal sheets 200 pm thick by wet chemical etching. The channel dimensions were length 33 mm, width 500 pm and depth 200 pm. Therefore, the channels were completely etched through the sheets and the channel depth could be varied by introducing several of these sheets into the reactor. The flow distribution between the 20 channels of the device was performed by triangular inlet and outlet fields. Both devices had outer dimensions of 70 mm x 40 mm x 30 mm. 

Electrical heating, through the use of heater coils, strips, or cartridges, is the most popular method. Higher temperatures for faster cycles are easily obtained. Recognize that electric mold heating is only as fast as the wattage put into it. It is a cleaner system than steam that was used many decades ago. 

Several approaches were used for the temperature control, for example, heating of the lines, pumps, valves mixing head, etc., by electrical resistance heating by means of heating cartridges and tracing lines, as well as by the recirculation of heated oil through jacketed tanks and lines. The methods used depend on the specific requirements of the application and the complexity of the machines. 

Fig. 6.12 Microstructured electrical heat exchanger with channel-on-a-circle design. Left assembled device right microstructured inner cylinder, partly out of the hollow cylinder housing. (Courtesy of the American Chemical Society.) The recess inside the inner cylinder serves for carrying the heating cartridge.

Electric cartridge heaters are often used to heat elastomer molds and thermoset molds. Figure 4-9 shows a schematic diagram of an electric heating system. In this case, cartridge heaters are inserted into bores in the mold to achieve temperatures of 150-200°C (300-400°F) required for cross-linking. 

Injection molds are machined from a variety of tool steels and then hardened or in some cases plated with chromium, nickel, or proprietary materials. Large molds use prehardened tool steels because they cannot be hardened after machining. 124 Stainless steel is employed for some smaller molds, particularly those used for optical and medical parts and for corrosion resistance. Since they provide better heat transfer and, thus, shorter molding cycles, materials such as beryllium copper are used as inserts in critical areas. Injection molds are usually cooled or heated with water, although oil or electric heater cartridges are employed for high-mold temperatures. Mold-temperature controllers pump water into the manifolds and then into cooling fine machine into the molds. 

Injection molds are usually cooled or heated with water, although oil or electric heater cartridges are used for high mold temperatures. Mold temperature controllers pump water into the manifolds and then into cooling Unes machined into the mold. 

Watt-Flex, Split-sheath cartridge heater, Dalton Electric Heating Co., Inc. 

Reaction can be initiated by several means, aH of which depend on deHvery of heat at a relatively high temperature to a starting cone. Cartridge-actuated and electric match units are usuaHy used. The former is in the majority. A water-activated unit has been described (12). The heat generated by the starting device initiates reaction in a cone, which is a smaH amount of candle that is higher in fuel content, eg, 30 wt % iron. Compared to... 

A hot press was made using a hydraulic 20 ton shop press, and two homemade aluminum heating plates. Each heating plate was drilled to accept an electric cartridge heater and a thermocouple. A temperature controller was connected to the heater and thermocouple on each heating plate. 

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