Components. Installation Guidelines

Transcription

1 omponents Tubular eaters esign & Installation Guidelines esign onsiderations Material For resisting corrosion inherent in the process or environment and for withstanding the sheath temperature required Standard sheath materials are INOOY, steel, copper and stainless steel (type 04). Other types of stainless steel, MONE, titanium and INONE are available. Job equirements The calculation of total heat requirements for an application is outlined in Technical section. For assistance, contact your ocal hromalox field sales engineer who will be glad to contribute his judgement, experience and knowledge in solving your heating problem. fter the specific heater size and rating has been tentatively selected, the watt density must be checked against the curves in Technical section. If the heater selected has a watt density higher than stipulated by the curve, consider these alternatives:. Use more heaters of a lower watt density to obtain the required kw capacity. 2. educe the kw capacity needed by reducing heat losses and/or allowing for a longer heat-up time. Watt ensities The watt density of the element, or watts per square inch of element heated area, should be low for heating asphalt, molasses and other thick substances with low heat transferability. It can be higher for heating air, metals, liquids and other heat-conducting materials. See curves in Technical section for determining allowable watt densities. When high operating temperatures are needed, watt density must be limited in order not to exceed the maximum sheath temperature. Watt density is given in the specifications for each tubular heater. In general, a viscous material with low thermal conductivity requires a low watt density. igher watt densities can be used with thinner liquids and with materials of high thermal conductivity. Premature loss of the element due to excessive temperature may result if the material s heat-take-away ability is low. lso, the material may be charred, carbonized or its chemical makeup altered by overheating. Terminal Selection Stocked tubulars are shipped with standard terminals, see Terminal Options in this section. Many other terminals and terminal end seals are available made to order. UTION Protect terminals from possible contamination from surrounding atmospheres such as oil fumes, chemical vapors from other processes, moisture, weather, etc. MgO insulation is hygroscopic. Vacuums Tubular heaters operate at higher temperatures in a vacuum because there is no air to take away the heat. Therefore, watt densities are recommended to be 20 to 0% lower. It is recommended terminals of the element be kept outside of the vacuum. ode ompliance hromalox manufactures the highest quality heaters and controls and, where applicable, in compliance with such codes as the anadian Standards ssociation (S), Underwriters aboratories Inc. (U) and Verification of evices for Europe Testing and ertification Institute (VE) and E. Installation Guidelines Wiring Must be in accordance with The National Electrical ode (NE). It is important to use the correct wire gauge to carry the amperage required. wire not large enough can overheat, become brittle and break. The ambient temperature must also be considered in choosing the correct type of wire and insulation. Make sure wiring to terminals is tight. Keep terminals away from heat, if possible. (For higher temperatures, contact your ocal hromalox Sales office.) Mounting Methods Elements can be supplied with threaded fittings for mounting thru walls of tanks, ovens, etc. ompression threaded fittings are also available for easy field installation. ings, clips, brackets and washers can also be attached to elements for mounting purposes. Easy ending To put heat where it is needed, tubular elements can be bent to fit most requirements. See following pages for customer bending and factory bending details. ending should be done around a smooth round object such as a piece of pipe. For minimum bending radii, see ending Guidelines. Triangular ross-section These unique cross-sectioned elements are specially designed for high element surface temperature applications, and wherever extreme rigidity is required. Triangulation patented extra step by hromalox to increase insulation density and maximize heat transfer and operating life. This method of compaction increases uniformity of resistance wire spacing to help eliminate hot and cold spots. It also increases the rigidity of the element, which is an advantage in some applications. The terminal ends of these elements are re-rounded to facilitate the use of threaded fittings or other mounting methods. The heart shaped cross-section is recommended for certain heavy duty applications. It has added structural strength, achieved through die pressing, which resists deformation or sagging when installed in the flow of high velocity air or thick oils and compounds, or in high surface temperature air heating. G F E Insulation eated ength E F G Terminal Size imensions (In.) Terminal Material E F G Size opper /8 2/64 -/8 ±/6 #0-2 Steel or INOOY /8 2/64 -/8 ±/6 #0-2 opper, Steel or INOOY /2 5/2-7/6 2-/2 /6±/6 #8-2. See complete heater dimensions in table on product pages. -6

2 omponents Tubular eaters Modifications World eader in the Manufacture of Electric eating Elements hromalox offers the most complete line of tubular heaters available. Standard diameters are: Standard iameters } ound Triangular /8 /2 } (heart shape) /8 7/6 } Flat Pressed ross-section Views ound ross Section ighly adaptable where elements must be bent particularly if bending is performed in the field. Triangular ross Section Patented process produces elements with the closest possible dimensional control. Triangulated ross Section Flat pressed. Patented process provides large contact area for clamp-on applications. This means more efficient heat transfer, fewer elements since higher element ratings may be employed. Voltage or Wattage eaters can be made for operation on any voltage and rated at any wattage suitable for the application within practical limits. For voltages higher than V, specify high voltage terminal construction. See omponent section Tubular eater ( or /2" diameter only). Special Wattage istribution eaters can be made with higher wattages toward the end of the heated section to help offset losses in certain applications. heck with your ocal hromalox Sales office for additional information. Tubing Standard industrial grade wall thickness: epressed ends Tubulars can be bent to tighter radii at the factory. ends are then repressed to ensure re-compaction of insulation for long life. ustomer bending on larger radii does not require repressing. (See Factory ending Guidelines in this section). ength arger diameter heaters can be made in unspliced lengths up to 5 feet. This eliminates the need for a spliced joint which is always a possible weak point that might cause premature heater failure. Max. eater Element (In.) ength (Ft. ± %) /8 7±/8" /2 7±/8 Note Single-end elements have a maximum sheath length of 0 feet. Terminal onstruction Many choices to suit your application. Tubular elements generally have a terminal for electrical connection at each end. Single end construction has both terminals at the same end. U and S hromalox tubular heaters can be furnished as U ecognized and S ertified components with the addition of a terminal end seal. Terminal end seals can be added to stock elements and shipped in one week. (U File E98, Guide UJY2, S File 40859). Use end seal/moisture barrier in place of end seal. In addition, titanium and other 00 series stainless steel sheaths are available upon request. For applications requiring other materials, contact your ocal hromalox Sales office. old Section onger cold ends can be supplied, as required, up to 20 inches. For longer cold ends, contact your ocal hromalox Sales office. Factory ending Tighter bends can be made at the factory. Tubular heaters can be formed to many different shapes to suit your application. This is done by specially designed bending tools and repressing dies for bending on many different radii. dditional Features Many additional features are available for the difficult jobs which require custom designed elements employing hromalox's vast engineering experience. Threaded Fittings Nickel Plated Steel Washer VE and E hromalox tubular heaters can be furnished as VE ertified and E certified. ontact your ocal hromalox Sales office. Wide hoice of Materials vailable to meet a wide variety of applications. Standard sheath materials are: INOOY, steel, type 04 and 6 stainless steel, copper, INONE and MONE. Max. Wall imensions (In.) Element Fitting Mtg. ole Thickness Thrd. Size (In.) Material (In.) (In.) F rass /2 7/2 /8-24 5/2 0.5 rass 5/2 5/6 7/6-28 /6 /8 rass 7/2 5/6 /2-28 /6 /2- rass 2/2 5/6 5/8-24 / Steel /2 7/2 /8-24 5/2 0.5 Steel 5/2 5/6 7/6-28 /6 /8 Steel 7/2 5/6 /2-28 /6 /2- Steel 2/2 5/6 5/8-24 / Stainless Steel /2 7/2 /8-24 5/2 0.5 Stainless Steel 5/2 5/6 7/6-28 /6 /8 Stainless Steel 7/2 5/6 /2-28 /6 /2- Stainless Steel 2/2 5/6 5/8-24 /6 Gasket Washer Welded or razed ing Tubular -7

3 omponents Tubular eaters Factory ending Guidelines Figure Figure 2 Note O represents overall length. O = " O = " + Figure Figure 4 2 O = " Factory Minimum ends for Tubular eaters Element & /2" INOOY 5 Steel & opper " INOOY Steel & opper 0.40" INOOY Steel & opper /8" INOOY 5 Steel & opper 0.75" INOOY Steel & opper 0.5" INOOY Steel & opper 0.260" INOOY Steel & opper 0.245" INOOY Steel & opper O = " Inside imensions (In.),2,,2 Inside E -/8 5 8 /2 -/ /8 8 /2 -/8 6 7/6 -/8 8 7/6 -/8 6 9/6 -/6-5 /8 -/6 6 /8 -/6 2-5/8 5 /8 9/6 5/6 /8 -/6 -/6 -/6 -/8 -/8 -/6 -/6 -/6 -/6 2-5/ " INOOY - 5 To Order Specify model, PN, volts, watts, special features, if required, and quantity. Specify for Factory Formed Tubulars:. Figure number..,,2,,, E,, J, K,,2 and,2, dimension as required.. N - number of turns, - Element iameter- aid < - angle as required.. Material for threaded fittings. E. Special terminal type. F. Position of crown (flat side) of element (T, TI, TS only). G. Submit sketch with special details. Notes. These are general guidelines only. Special dimensions and configurations are possible. ontact your ocal hromalox Sales office. 2. dimension can be less if no fittings are required.. dimension may need to be greater if special fittings are used. 4. E dimension is a minimum when dimension is less than customer minimum bending radius. 5. eart Shaped cross-section only

4 omponents Tubular eaters Factory ending Guidelines (cont d.) Figure 5 Figure 6 Figure 7 Tubular 2 O = O = I + 2 (X-) (X) +.4 (X-) - (2X-)0.4 X = No. Outside airpins Figure 8 Figure 9 Figure 0 4 I O = I I E J <. 2 O = 0.075(<. )(2/2 + ) O = E O = Figure Figure 2 Figure K J O = ( + ) O = ( + ) O = [( + )(.4)(Number of 60 s)] + 2 Figure 4 Figure 5 Figure 6 K J View View I 2 O = [( + )(.4)(No. 60 s)] + (/2) + K + O = O =

5 Tubular eaters Terminal Options Standard, lternate and Moisture esistant Terminals omponents Max. Type escription (In.) Volts Standard Terminals / Mica 0.4 Per Tab Welded on threaded pin (#0-2), nut Mica 0.5 Max. Type escription (In.) Volts Mica Per Tab Welded on threaded pin (#8-2), nut Per Tab Threaded terminal pin (#8-2), nut Per Tab Terminal connector - 5/6" long, #0-2 machine screw lternate Terminals / Mica Per Tab / eadwire with sleeving, #6 onnector STI/ 0.5 STS/ ST Single-end tubular termination, 0" leadwire 0 ll Per Tab Per Tab Threaded terminal pin (#8-2), nut Mica rk-es onnector 0 Per Tab ll Threaded terminal pin (#8-2), nut Per Tab 5/6" ong #0-2 olt with nut ight-angle rk-es onnector / Extra mechanical strength # 8-2 thread -0

6 omponents Tubular eaters Terminal Options (cont d.) Standard, lternate and Moisture esistant Terminals Max. Type escription (In.) Volts lternate Terminals (cont d.) 8 (In.) 0.5 / /2 0.4, 9/6 Per Ta b Max. Type escription (In.) Volts / Per Ta b 0.4 Narrow profile terminal connector, -5/8 5/6" ong #0 2 or #8 2 eadwire type terminal machine screw /50 eramic Spacer /2 0.5 Tubular - /2 Silicone ushing 2 7/6 Silicone bushing/ceramic disc seal, epoxy/tv/silicone resin can be placed under bushing (type 49, #8 2 thread/ 05 leadwire, silicone sleeving type 50, #0 2 thread) 47-M Per Ta b # /2 2 eramic ushing -/8 200 leadwire, silicone sleeving ir set cement, >700 F temp. Moisture esistant Terminals Note: Type 26 is the only ermetic Seal, all others are arriers / /6 5/ /6 0.5" and Smaller / " and arger 0.4" and arger 2-/8 ermetic seal, 000 F max. element temp Per Ta b #8-2 eramic ushing EPM rubber vulcanized to sheath Epoxy, 94 F max. temp., (type 9) and leadwire, max. temp. 220º F TV, 50 F max. temp., (type 40) Per Ta b 0.5 # Silicone 0.4 ubber oot Per Ta b " and Smaller 6 Gauge ead Wire Per Ta b /2 #0-2 eramic ushing Epoxy, 94 F max. temp., (type 9) TV, 50 F max. temp., (type 40) V VP /2 4 Silicone rubber boot potted with TV sealant, " dia. single end only V Seal (284 F) V Seal Plus (92 F) Seal ( imit) Seal (600 F) Seal (00 F) to -

7 omponents Tubular eaters ustomer ending & ccessories rackets, iscs & lips rackets, iscs and lips Various types of brackets and clips can be fastened to the heaters to facilitate installation. The following are typical. For other brackets to meet your installation requirements, contact your ocal hromalox Sales office. /2" -5/6" 4-/2" -/8" Flange - Support 0.5" Element Elements are on " olt ircle isc " /2" -7/6" -5/6" " O.. ompression Fittings 4-/2" -/8" Flange - Support " Element 7/6" 5/2" lip-nchor " " Field Installed ompression Fittings For, 0.5 and 0.246" diameter elements. vailable in both brass and steel, these fittings have been tested to 600 psi hydrostatic pressures and may be used in tank walls for liquid immersion as well as in air ducts and a variety of other applications. ompression fittings do not require brazing and can be field mounted in minutes. They may be positioned anywhere along the cold section of the heating element. o not position over heated section. annot be installed over terminal Type #26 (ermetic Seal), and some other terminals wider than sheath diameter. ex Nut Washer Tank Wall Gasket Thread F ompression Nut Fitting Ferrule Thread G ompression Fittings for, 0.5 and 0.246" iameter Elements for Installation in the Field. ustomer ending Simple element configurations can be made easily in the field from stocked tubulars listed in this catalog. If copper or stainless sheaths are selected, specify To be fully annealed for bending. Elements can be bent around any round, smooth surface of the right diameter. Three precuations should be observed to prevent damage to the element:. adius of the round object, around which the element is bent, should be no smaller than the minimum radius for the element, as shown in the table below. 2. Sharp edges of tools should not be permitted to gouge the element sheath while bending.. End of cold section of the element should not fall within the bend nor come within " of either side of the bend. To locate eave " Min. Straight Section at Terminal End End of eated Section Must Not e Within These Two Points Terminal End imensions (In.) end of cold section, see dimensions for the element on its catalog page and determine as follows: Example To locate end of cold section of TI-645 tubular element, refer to the individual product page. length: 6" ess heated length: 9-/8" Total cold length: 6-" old length of each end (6-" 2) = -7/6" Terminal end bending can be done with pipe section of slightly larger diameter than sheath. minimum " straight section should be left at the end. Note To protect sheath, copper sheet can be bolted to vise jaws and end of pipe can be filed to remove sharp edge. efore bending, it is best to lay out and dimension the configuration. lso, it is best to start bending from the center of the heater and work toward the terminal ends. ustomer ending Min. Inside adius (In.) Material egree of end /2" " 0.40" /8" 0.75" 0.5" 0.26" 0.246" 0.2" opper /2 -/2-5/6-5/6 2-5/6 2-5/6 -/8 -/8 5/6 5/6 Not Std. Mat. Steel 90 2-/2-5/6 - -/8 5/6 in this 80 2-/2-5/6 - -/8 5/6 lloy /2 2-/2-5/6-5/ /8 -/8 5/6 5/6 5/8 5/8. For radii smaller than shown, special processing is required to achieve good life qualities. ontact your ocal hromalox Sales office. ending Thread Size ssembled Elem. Mtg. ole Max. Wall Overall Material Thickness ength F G PN rass /2 7/2-7/6 /8-24 / rass 0.5 5/2 5/6 7/6-28 / rass 2/2 5/6 2 5/ Steel /2 7/2 - /8-24 / Steel 0.5 5/2 5/6-7/6-28 / Steel 2/2 5/6 2-/8 5/ To Order Specify PN, material, element diameter and quantity. vailable in pairs only.. vailable only in brass and steel at this time. -2