Heat actuating device

Thermostats—bimetallic strip, snap-action disk, and thermostatic cable Continuous discrete conductors Thermistor sensors Rate of temperature rise Copper tubing heat-actuated devices (HADs) Thermoelectric Combined rate of rise/fixed temperature Rate compensation Oil mist ... 

H.A.D.(Heat Actuating Devices) Thermostatically controlled devices used to activate fire equipment, alarms, or appliances. 

In 1951 Day Zimmermann, Inc. was awarded an initial contract to operate the Lone Star Army Ammunition Plant. Fire protection systems for equipment and processes consisted of fuzeable links and quartzoid bulbs for sensing fires. In the early 1950 s, a plan was initiated to replace the existing systems with the improved Heat Actuating Device. The H-A-D greatly improved the effectiveness of the deluge systems and was considered adequate at the time. 

Pressure devices should be designed to maintain constant pressure on the bond during the entire cure cycle. They must compensate for thickness reduction from adhesive flow-out or thermal expansion of assembly parts. Thus, screw-actuated devices like C-clamps and bolted fixtures are not acceptable when constant pressure is important. Spring pressure can often be used to supplement clamps and compensate for thickness variations. Deadweight loading may be applied in many instances however, this method is sometimes impractical, especially when heat cure is necessary. 

Insensitivity of the plant to operator errors and CPS failures is attained owing to the passive principle for reactor shutdoAvn and residual heat removal in combination with primary coolant natural circulation, the reactor power self-regulation capability and availability of self-actuated devices. The reactor will be shutdown and brought into a safe state irrespectively of the estimation of the plant state and action by the operator. 

Fabrication technologies for elements of normal operation and safety system, ensuring high reliability of the self-actuated devices, pressurizers, tanks, heat exchangers, pumps, and filters. 

Figure 16. Integrated sensor-actuator device for local heating and temperature/conductivity measurement.

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... 

In addition to the circuit breaker, there have been a number of other SMA appHcations for various functions in electric power generation (qv), distribution, and transmission systems. One such device is a thermal indicator that provides a signal visible from the ground of a hot junction or connector in a distribution yard. Such hot spots occur as a result of the loosening of bus bar connectors owing to cycHc temperature as the electric load varies. In addition to the use of SMA flags as a hot-spot indicators, actuators that automatically maintain the contact force in a bus bar connection have been demonstrated. Based on a BeUeviHe washer fabricated from a Cu—Al—Ni SMA trained to exhibit two-way memory, these washers, when heated by a hot joint, increase their force output and correct the condition. A 30 mm diameter washer 3 mm thick can produce a force of over 4000 N. Similar in purpose... 

The sudden mixing of large amounts of reactants under heating, instead of cooling, caused a runaway reaction. Once the pressure reached 16 bar pressure safety devices were actuated, the temperature at that point had reached 160°C,... 

Li, H. B., and Bashir, R. (2002). Dielectrophoretic separation and manipulation of live and heat-treated cells of Listeria on microfabricated devices with interdigitated electrodes. Sens. Actuators B Chem. 86, 215-221. 

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