Immersion heater

A suitable heating lamp or other heating device. The author has found the 250 watts vertical pattern radiator lamp ( sausage lamp) or, alternatively, the Santon 250 or 500 watts immersion heater f to give excellent results. 

SHW 2125 Warning Danger of explosion m oil fuel storage tanks fitted with immersed heaters... 

Fauskes Assoeiates Ine. developed the RSST as an inexpensive sereening tool [15,16]. The RSST (Figures 12-14 and 12-15) eonsists of a spherieal glass reaetion vessel and immersion heater (optional). 

Bath-type heat exchangers can be either direct or indirect. In a direct bath exchanger, the heating medium exchanges heat directly with the fluid to be heated. The heat source for bath heaters can be a coil of a hot heat medium or steam, waste heat exhaust from an engine or turbine, or heat from electric immersion heaters. An example of a bath heater is an emulsion heater-treater of the type discussed in Volume 1. In this case, a fire tube immersed in the oil transfers heat directly to the oil bath. The calculation of heat duties and sizing of fire tubes for this type of heat exchanger can be calculated fom Chapter 2. 

There are many other types of heat exchanger devices that can be used to heat the gas above the hydrate temperature. These could include shell and tube heat exchangers, electrical immersion heaters, furnaces, etc. However, the most common equipment type used to heat a well stream is the indirect fired water bath heater. 

Packing/cylinder lubrication can be provided from a forced feed compressor lube oil system. For very cold installations, immersion heaters and special lube oils must be considered. If the lube oil temperature gets too cold, the oil becomes too viscous and does not flow and lubricate properly. 

Storage tanks can be heated with thermostatically controlled steam coils, hot-water coils, electric immersion heaters or a combination of these. The elements and their... 

Storage tanks should, wherever possible, be installed above ground. The site selected should not be in an unduly exposed position. Clearance must be allowed for the withdrawal from the tank of fittings such as immersion heaters and steam coils. Where tanks are installed inside buildings, they should generally be located within a tank chamber, although in some industrial installations such as steelworks and foundries, a tank chamber may not be necessary. The requirements of insurance companies and local authorities should be considered when designing these installations. 

Heating should ensure temperature control to 1°C and may be electric immersion heaters or steam coils. 

Galvanising baths are generally constructed from special mild steel boiler plate having very small amounts of trace elements so that they are not rapidly attacked by molten zinc but they can be made of ceramic materials and heated from the top or by immersion heaters. 

Cooling towers and evaporative condensers may freeze in winter if left operating on a light load. A common arrangement is to switch off the fan(s) with a thermostat, to prevent the formation of ice. The water-collection tank will have an immersion heater to reduce... 

Apart from such requirements for head pressure control, winter precautions are needed to prevent freezing of the water while the plant is not rejecting heat to it. These commonly take the form of an electric immersion heater in the water tank, together with lagging and possible trace heating of exposed pipes. In some systems, the evaporative condenser itself may be within the building, with air ducts to the outside. In severe climates, external tanks need to be lagged to conserve the heat provided by the immersion heater. 

Immersion heaters. An immersion heater consisting of a radiant heater encased in a silica sheath, is useful for the direct heating of most acids and other liquids (except hydrofluoric acid and concentrated caustic alkalis). Infrared radiation passes through the silica sheath with little absorption, so that a large proportion of heat is transferred to the liquid by radiation. The heater is almost unaffected by violent thermal shock due to the low coefficient of thermal expansion of the silica. 

The heat transfer coefficient (/i) has been determined by measuring the temperature difference between the immersed heater and the bed. The h value increases with increasing Ug (Fig. 1(a)), but exhibits a maximum value with increasing (Fig. 2(a)). The effects of Ug on h is dominant, since the bubbling phenomena become more vigorous due to the... 

If 1000J of electrical energy is added with an immersion heater to 55.7g of water at 20.0°C, (a) how much heat is added (b) how much work is done on the system (t ) how much does the temperature rise ... 

Contamination of silicone oil baths with alkaline or acidic materials may lead to depolymerisation and a marked lowering of the flash point. This happened when the alkaline contents of a beaker heated in a silicone bath at 260°C frothed over into the oil, which itself then frothed and overflowed, exposing the electric immersion heater element which ignited the decomposition products. 

When specified, a removable steam heating element external to the oil reservoir or a thermostatically controlled electric immersion heater with a sheath of austenitic stainless steel shall be provided for heating the charge capacity of oil before start-up in cold weather. The heating device shall have sufficient capacity to heat the oil in the reservoir from the specified minimum site ambient temperature to the manufacturer s required start-up temperature within 12 hours. If an electric immersion heater is used, the watt density shall not exceed 2.33 watts per sq. cm (15 watts per sq. in.). 

Exact temperature control is very important in polymerization reactions, since, among other things, the rate and degree of polymerization are strongly dependent on temperature. For accurate work, for example, for kinetic analysis with a dilatometer, a thermostat filled with water or paraffin oil may be used instead of thermostatting in the normal way with the aid of a contact thermometer and an immersion heater. 

Often it is necessary to heat transfer lines to ensure that products do not gel in the line during cold weather. Both electrical heating and steam heating can be used to trace lines. Only explosion proof electrical heat tape and thermostats can be used on fuel systems. Immersion heaters are not recommended for fuel and fuel additive applications. 

Figure 7-3 Kjeldahl distillation unit employs electric immersion heater in flask at left to carry out distillation in 5 min. Beaker at right collects liberated NH3 in standard HCI.

Any steam coil or immersion heater used for heating the contents of the vessel should be situated not less than 4" away from the rubber lined surface to avoid local overheating. While heating by steam injection for curing, care should be taken to avoid direct impingement of steam onto the rubber surface. 

This paper describes an ebulliometric system for routine and special determinations of molecular weights. The system uses a simple ebulliometer, an immersion heater, and a Cottrell-type pump. Temperature sensing is by differential thermopile. Precision varies from about 1 to 6%, and values compare well with those from other laboratories and those from other methods. Values as high as 170,000 have been successfully measured. Some problems encountered in using the ebulliometric method are selection and effect of reference temperature, limitations of the vapor lift pump and a possible substitute for it, measurement of equilibrium concentrations within the operating ebulliometer, and the experimentally determined ebulliometric constant and some factors which influence its value. 

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