Tube design

The specific advanced properties of the ceramic insulator eliminate the need for oil or resin insulation. The metal vacuum envelope of the tube provides higher beam stability, more robust design, and even X-ray shielding up to certain levels. Furthermore, even difScult mechanical problems (e.g. mounting, coohng, or beam emission) can be solved by an appropriate customised tube design. 

To provide a tube design which makes possible a large variety of applications. 

There has been built a broad range of varieties of the basic tube design already ... 

At present time, our company is running a development project on the production technology of the MCB type X-ray tubes. The goals of this project are the improvement of the existing technology and making available new tube designs in the near future. 

Stability is a major issue in radiometric applications and asks for a special tube design and processing as well. 

As the anodes of the cathode-grounded tubes are cooled through the ceramic insulator, narrower insulators should lead to more heat transferable. For lower voltages, tube designs with twice the actual anode load are feasible. 

Microwave tubes for other ISM bands are not commonly available as tubes designed specifically for ISM use. Available tubes, generally of military and communications types, are more expensive. Reasonably priced tubes exist at 0.915 GHz at high (>25 kW) power, but not at 5.8 GHz and higher, or at... 

The hydrocarbon gas feedstock and Hquid sulfur are separately preheated in an externally fired tubular heater. When the gas reaches 480—650°C, it joins the vaporized sulfur. A special venturi nozzle can be used for mixing the two streams (81). The mixed stream flows through a radiantly-heated pipe cod, where some reaction takes place, before entering an adiabatic catalytic reactor. In the adiabatic reactor, the reaction goes to over 90% completion at a temperature of 580—635°C and a pressure of approximately 250—500 kPa (2.5—5.0 atm). Heater tubes are constmcted from high alloy stainless steel and reportedly must be replaced every 2—3 years (79,82—84). Furnaces are generally fired with natural gas or refinery gas, and heat transfer to the tube coil occurs primarily by radiation with no direct contact of the flames on the tubes. Design of the furnace is critical to achieve uniform heat around the tubes to avoid rapid corrosion at "hot spots."... 

Draft Tube Designs and Spouted Beds A draft tube is often employed to regnlate particle circnlation patterns. The most common design is the Wurster draft tnbe flnidbea employed extensivelvin the pharmacentical industry, nsnally for coating and layered growtJi applications. The Wurster coater nses a bottom positioned spray, bnt other variations are available (Table 20-47). 

Evaporators—These usually utilize a fin-tube design. Spirally finned tubes of 1.25 in to 2 in outer diameter (OD) with three to six fins per ineh are eommon. In the ease of unfired designs, earbon steel eonstruetion ean be used and boilers ean run dry. As heavier fuels are used, a smaller number of fins per ineh should be utilized to avoid fouling problems. 

Detector Tubes/Pumps Detector tube pumps are portable equipment which, when used with a variety of commercially available detector tubes, are capable of measuring the concentrations of a wide variety of compounds in industrial atmospheres. Operation consists of using the pump to draw a known volume of air through a detector tube designed to measure the concentration of the substance of interest. The concentration is determined by a colorimetric change of an indicator which is present in the tube contents. 

In order to improve the heat transfer characteristics of air cooled exchangers, the tubes are provided with external fins. These fins can result in a substantial increase in heat transfer surface. Parameters such as bundle length, width and number of tube rows vary with the particular application as well as the particular finned tube design. 

Data of Dunlap and Rushton is given in [6]. This tube design can prevent the need for I ertical baffles in a tank, and the heat transfer is good. 

Figure 10-96B. Horizontal thermosiphon reboiler on distillation column shell and tube design, not kettle. Boiling in shell.

Commonly used for heating or cooling very corrosive fluids that require expensive corrosion-resistant materials. Less economical than U-tube design for in-tank heating. 

The design and development of the Autrometer, as sketched by Behr,6 give us an excellent opportunity to indicate by reference a, number of items that were considered by its designers. (1) The need for better Coolidge tubes (9.4). The FA-100 series of x-ray tubes designed for the Autrometer has a peak of 100 kv, and a top rating of 3.5 kw with full-wave rectification, or 2.5 kw at constant potential,... 

Some major steps forward in the development of WT boilers were the invention of bent tube designs, the use of pulverized fuel, the development of integral furnace boilers, and other design innovations. 

Any of various types of heat transfer equipment, whereby relatively cold water flowing over a surface will, by conduction and convection means, transfer heat away from a process. The most common types of heat exchangers are plate and frame and shell and tube designs. A boiler is also a type of heat exchanger. 

Add identical reactors in parallel. The shell-and-tube design used for heat exchangers is a common and inexpensive way of increasing capacity. 

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