Heating coils

Shipment, Stora.ge, ndPrice. Butenediol is available in unlined steel tank cars, tank trailers, and various sized dmms. Because of its relatively high freezing point, tank cars are fitted with heating coils. The 1991 U.S. bulk price of technical grade butenediol was about 5.36 /kg. 

For commodities that soHdify at temperatures commonly encountered during shipping, tank cars are equipped with internal or external heating coils. In some cases, cars are insulated with both sides of the insulation protected by thin steel shells. Approximately 15% of the tank cars in the United States are constmcted for the transportation of pressuri2ed commodities, such as anhydrous ammonia and propane. 

Shipment and Storage. 2-Pyrrohdinone is available in steel dmms and in aluminum or stainless-steel tank cars and tank trailers. Because of its high freezing point, bulk shipments are in tanks with heating coils. Heating with hot water rather than steam avoids product discoloration. Steel (qv), stainless steel, and aluminum are satisfactory materials for storage containers. Because 2-pyrrohdinone is hygroscopic, it must be protected from atmospheric moisture. 

Shipment and Storage, Specifications. A/-Vinyl-2-pyrrohdinone is available in tank cars and tank trailers and in dmms of various sizes. Shipping containers are normally steel or stainless steel. Tank cars are provided with heating coils to facihtate unloading in cold weather. Rubber, epoxy, and epoxy—phenohc coatings are attacked and must be avoided. Carbon steel has been successfully used for storage tanks, but stainless steel preserves product quahty better. Aluminum and certain phenohc coatings are also satisfactory. 

Siace dimer acids, monomer acids, and trimer acids are unsaturated, they are susceptible to oxidative and thermal attack, and under certain conditions they are slightly corrosive to metals. Special precautions are necessary, therefore, to prevent product color development and equipment deterioration. Type 304 stainless steel is recommended for storage tanks for dimer acids. Eor heating coils and for agitators 316 stainless steel is preferred (heating coils with about 4s m (50 ft ) of heat transfer surface ia the form of a 5.1 cm schedule-10 U-bend scroU are recommended for a 37. 9-m (10,000-gal) tank. Dimer acid storage tanks should have an iaert gas blanket. 

Conveying-screen diyers are fabricated with conveyor widths from 0.3- to 4.4-m sections 1.6 to 2.5 m long. Each section consists of a sheet-metal enclosure, insulated sidew s and roof, heating coils, a circulating fan, inlet-air distributor baffles, a fines catch pan under the... 

Thermal expan sion. Equipment and pipehues which are liquid-full under normal operating conditions are subject to hydrauhc expansion if the temperature increases. Common sources of heat that can result in high pressures due to thermal expansion include solar radiation, steam or other heated tracing, heating coils, and heat transfer from other pieces of equipment. 

Figure 4.17 Corroded copper tubes from a heating coil. Cooling water contacted the visible surface. The mounds consist of copper carbonate (see Fig. 4.18).

The elements of a PM plan include periodic inspection, cleaning, and service as warranted, adjustment and calibration of control system components, maintenance equipment and replacement parts that are of good quality and properly selected for the intended function. Critical HVAC system components that require PM in order to maintain comfort and deliver adequate ventilation air include a outdoor air intake opening, damper controls, air filters, drip pans, cooling and heating coils, fan belts, humidification equipment and controls, distribution systems, exhaust fans. 

U = Overall heat-transfer coefficient of heating coil Btu (ft ) ( F) (hr)... 

For services where the heating coil may be exposed to cold or autorefrigerated liquids, the design should be such as to prevent blockage by freezing of steam condensate. The following methods are available to achieve this ... 

The calculations show that the volume of each reactor is 0.429 m and a heating coil is not required in the first CFSTR, whose area is 0.0713 m2. The areas of the subsequent heating coils are 0.466 m2 and... 

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