HotRod Cartridge Heaters STANDARD The engineers at Marathon Heater have developed a cartridge heater that exceeds the performance and durability of other cartridge HOTROD heaters. Through refinements in the swaging process, specially designed cores, careful selection of magnesium oxide fill, FEATURES nickel chromium resistance wire, stainless steel tubing, and carefully controlled production processes, 1. High temperature lead wires for HotRods routinely outperform other cartridge temperatures up to 450 C. heaters in difficult applications. 2. High impact ceramic cap retards HotRods are available in a wide contamination and is suitable for high variety of diameters and vibration applications. Deep holes in cap prevent configurations. Choose from fraying of leads when bent. our large selection of stock heaters for 3. Nickel-chromium resistance wire for maximum heater life, immediate delivery evenly wound for even heat distribution. or let the engineers at Marathon Heater 4. High purity magnesium oxide fill selected for maximum dielectric strength design a unique and thermal conductivity, highly compacted for maximum heat transfer. heater for your special application. Standard 5. 304 stainless steel sheath for oxidation resistance in a wide variety of environments. manufacturing times are 316 stainless steel and Incoloy are also available. Please consult the application guide normally less than 2 weeks. in the back for help in determining which material is best for your application. 6. TIG welded end disc to prevent contamination and moisture absorption. Length tolerance is ±3/32 or ±3%, whichever is greater. HotRods are UL recognized, File #E202904 and CSA certified, CSA file no. LR 109455-1. STANDARD SPECIFICATIONS Nominal Minimum Maximum Std. Lead Wire Max amps with Std. Max lead wire Maximum Maximum Volts Diameter Diameter Diameter Gauge Lead wire gauge amps 1/4.244.249 24 6 22 9 300 6.5mm.250.255 24 6 22 9 300 5/16.306.311 24 6 22 9 300 8mm.309.314 24 6 22 9 300 3/8.369.374 22 9 18 15 300 10mm.388.393 22 9 18 15 300 12mm.466.471 22 9 18 15 300 12.5mm.486.491 22 9 18 15 480 1/2.494.499 22 9 18 15 480 13mm.506.511 22 9 18 15 480 17/32.525.530 22 9 18 15 480 5/8.619.624 18 15 14 26 480 16mm.624.629 18 15 14 26 480 17mm.663.668 18 15 14 26 480 11/16.682.687 18 15 14 26 480 19mm.742.747 18 15 14 26 480 3/4.744.749 18 15 14 26 480 20mm.782.787 18 15 14 26 480 1.994.999 18 15 14 26 480 25.4mm.978.978 18 15 14 26 480 Camber tolerance is.025 per foot of length. Slight camber is not normally a problem since the heater will flex enough to enter a clean hole. Wattage tolerance is +5%, -10%. 2
OVERALL LENGTH Lead Arrangements HOTROD CONFIGURATIONS Swaged in Leads Swaged in leads are ideal for applications where there is a lot of movement or the leads must be bent sharply upon exiting the heater. Please note that for heaters over 3 long there is a short unheated section where the leads connect to the power pins. Also remember that if the heater is inserted completely into the hole, the leads are exposed to the block temperature (maximum o o temperature for standard leads is 450 C, 850 F). In heaters under 3 long, the leads go directly in to the core, resulting in an unheated section the length of the ceramic end piece. Heater Length Under 3 long Over 3 long Unheated Length at Lead End of Heater 1/4 5/16 3/8 1/2 5/8 3/4 1.20.20.25.30.32.32.32.70.70.70.80.85.85.85 In heaters over 3 long the leads make a connection with the power pins in a short unheated section. Crimped on Leads Crimped on leads are generally used where the temperature at the end of the heater exceeds the maximum rated temperature of the lead wire. Since the connection between the leads and power pins is made outside the heater, the unheated length at the lead end of the heater is kept to a minimum. Crimped on leads are not recommended for applications where the leads must be bent sharply near the heater, or in applications where the leads will be subject to a lot of flexing. The high temperature connectors are covered by 1-1/2 of 2500 volt silicone rubber coated fiberglass sleeving. Post Terminals Post terminals (also called screw terminals or stud terminals) are used in applications where easy lead replacement is desirable. They work great with ring terminals or fork terminals. Post terminals are only available for heaters ½ diameter and up. Terminals are #6-32 and supplied with 2 stainless steel washers and 2 stainless steel nuts on each stud. 1 1/4 5/8 Right Angle Leads Right angle leads are ideal for applications where space is limited. Leads are covered with a silicon impregnated fiberglass sleeve where they exit the heater. When ordering, please specify the overall length. UNHEATED LENGTH EXTENSION Unheated Length at Lead End of Heater Heater Length 1/4 5/16 3/8 1/2 5/8 3/4 1 Under 3.5 long.20.20.25.3.32.32.32 Over 3.5 long.70.70.70.80.85.85.85 Extension Length.25.25.25 31.31.31.37 Teflon Seal When an effective moisture or oil seal is needed, a swaged in teflon seal with teflon leads provides an effective barrier. Because it is necessary to keep the temperature of the teflon seal below 350 F, a 1" long unheated section is recommended. Standard lead gages apply. 1 UNHEATED 3
OVERALL LENGTH Silicone Rubber Seal A high temperature silicone rubber seal used with silicone rubber lead wires provides an effective moisture seal up to 400 F (200 C). It is generally the most impervious of the moisture seals. In order to protect the seal, a 1 unheated section is recommended. Epoxy Seal Epoxy potting forms a good moisture seal with more mechanical strength than a silicone rubber seal. Regular epoxy is rated at 350 F (177 C) and epoxylite is rated at 600 F (316 C). In order to protect the seal, a 1 unheated section is recommended. Swaged in Braid Swaged in stainless steel braid provides excellent abrasion protection while allowing the leads to be bent in a tight radius. Because the braid is swaged in, it is extremely resistant to pulling out of the heater. UNHEATED LENGTH Unheated Length at Lead End of Heater Heater Length 1/4 5/16 3/8 1/2 5/8 3/4 1 Under 3 long.35.45.25.25.32.32.32 Over 3 long.75.70.70.75.85.85.85 Right Angle Stainless Steel Braid Right angle stainless steel braid offers the same advantages as swaged in stainless steel braid but allows use in tight spaces. When ordering, please specify the overall length. UNHEATED LENGTH EXTENSION Unheated Length at Lead End of Heater Heater Length 1/4 5/16 3/8 1/2 5/8 3/4 1 Under 3.5 long.20.20.25.3.32.32.32 Over 3.5 long.75.75.75.85.85.85.85 Extension Length.25.25.37.37.37.37.37 Stainless Steel Flexible Conduit Flexible conduit provides maximum lead protection from abrasion but can not be bent as sharply as stainless steel braid. Flexible conduit is swaged into the heater for maximum protection. (Flexible conduit is also known as armor or hose). UNHEATED LENGTH Unheated Length at Lead End of Heater. Heater Length 1/4 5/16 3/8 1/2 5/8 3/4 1 Under 3 long.20.20.25.3.32.32.32 Over 3 long.75.75.75.85.85.85.85 Conduit O.D..27.27.27.47.37.47.47 Copper Coupler and Stainless Steel Flexible Conduit Flexible conduit can also be attached to the sheath with a copper coupler. This method can also be used to attach flexible conduit to stock heaters. 4
OVERALL LENGTH Right Angle Stainless Steel Conduit Right angle stainless steel conduit offers the sameadvantages as swaged in stainless steel conduit but allows use in tight spaces. When ordering, please specify the overall length. EXTENSION UNHEATED LENGTH Unheated Length at Lead End of Heater Heater Length 1/4 5/16 3/8 1/2 5/8 3/4 1 Under 3.5 long.20.20.25.3.32.32.32 Over 3.5 long.75.75.75.85.85.85.85 Extension Length.37.37.50.50.50.50.50 Conduit O.D..19.27.27.37.37.37.37 Copper Elbow and Stainless Steel Flexible Conduit Right angle flexible conduit can also be attached to the sheath with a copper elbow. This method can also be used to attach right angle flexible conduit to stock heaters. Hex Head Pipe Fittings Fittings are available in brass or stainless steel. Brass fittings are brazed on and stainless steel fittings can be either brazed or welded on. Please specify overall heater length and fitting material when ordering. Please consult the sheath suitability chart when ordering heaters for immersion applications. 1/4 5/16 3/8 1/2 5/8 3/4 1 NPT Thread Size 1/8 1/4 1/4 3/8 1/2 3/4 1 Fitting Length.56.66.66.77.84.93 1.34 Hex Size 7/16 9/16 9/16 11/16 7/8 1-1/16 1-5/16 Double Ended Threaded NPT Fittings Double ended fittings are normally used when it is desirable to mount a box on an immersion heater. Fittings are available in stainless steel and brass. Please specify overall heater length when ordering. 1/4 5/16 3/8 1/2 5/8 3/4 1 NPT Thread Size 1/8 N/A 1/4 3/8 1/2 3/4 N/A Fitting Length.98 N/A 1.13 1.25 1.81 1.98 N/A Flanges Hex Size 7/16 N/A 9/16 11/16 7/8 1-1/16 N/A Small flanges can be welded on the lead end of the heater. Flanges can be used to hold a heater in place to prevent backing out during operation. Flanges also assist in heater removal. Flanges are 1/16" thick. Flange Dimensions Flange OD 1 1-1/2 2 Can be used on 1/4, 5/16, 3/8, 1/2 1/4, 5/16, 3/8, 1/2, 5/8, 3/4 1/2, 5/8, 3/4, 1 Hole Spacing 3/4 1-1/8 1-1/2 Hole Size.144.156.201 5
Locating Ring Locating rings are used to position the heater and keep it from entering too far into the hole. Unless otherwise specified, the ring will be located 1/4 from the end of the heater. Thermocouples Type J and type K thermocouples can be installed to monitor part temperatures. A thermocouple mounted against the heater sheath in the center of the heater gives a good approximation of block temperature, especially when there is a good fit between the heater and the block. A thermocouple mounted in the tip is useful for monitoring liquid temperatures, or material flowing past the end of the heater. Unless otherwise specified thermocouple leads will be the same length as the heater leads. Standard thermocouple wire insulation is teflon, other types are available upon request. Please specify thermocouple type when ordering. Distributed Wattage: Distributed wattage Hotrods (with a higher watt density on the ends than the rest of the heater) can be used to compensate for end losses in blocks. Distributed wattage Hotrods are available in all diameters. HOT WARM HOT Bent HotRod o o HotRods can bent at any angle from 10 to 120. Heaters must be bent in an unheated sectionand can be constructed with most of the other options shown in this catalog. Heater Dia. ¼ 5/16 3/8 ½ 5/8 ¾ 1 Min Bend Radius ½ ½ ½ ¾ 1 1-1/4 N.A. Min Cold Lth 2.25 2.25 2.37 2.87 3.37 3.87 N.A. SJO Cord 2 conductor or 3 conductor SJO cord is available as a lead option for heaters 3/8" diameter and larger. On 3/8" and 1/2" dia heaters, the cord directly exits the heater. On 5/8" and larger diameters the cord is surrounded by epoxy where it exits the heater. Remember to allow 1 unheated at the end of the heater to keep from overheating the cord. Double Ended Heater HotRod cartridge heaters are also available with an electrical termination on each end. Heaters can be made with lead wires, straight pins, or screw terminals 6
Maximum Allowable Watt Density for Heating Metals Block Temperature in F Application Data 1200 1000 800 600 400 200 0.002 140 270 300 300 300 300 0.003 120 205 295 300 300 300 0.004 100 175 240 300 300 300 0.005 90 145 200 285 300 300 0.007 70 100 150 200 250 300 0.010 60 90 110 150 200 225 0.015 50 75 95 110 140 165 0.030 40 60 80 90 100 110 0.060 30 40 50 55 65 65 0.100 25 35 45 50 50 50 Sheath Suitability Chart Clearance is determined by taking the hole diameter and subtracting the heater diameter. Watt density is calculated by: Wattage Heated Lth x Diameter x 3.14 Cycling reduces heater life and high cycling applications should use lower numbers. Staying below these values will result in increased heater life. 304 SS 316 SS Incoloy Max Watt Density Max Temp ( F) Air to 1500 F E E E Air to 1600 F G G E Air to 1800 F NR NR G Acetic Acid F G F 40 180 Acetone E E E 20 130 Alcohol F E E 25 212 Asphalt E E E 4-10 200-500 Caustic Soda, 10% E E E 100 210 Degreasing Solution G E E 40 275 Electroplating Bath, Cadmium E E E 100 180 Electroplating Bath, Copper E E E 100 180 Ethylene Glycol F F F 30 Freon E E E 2-5 300 Glycerin E E E 10 500 Kerosene E E E 25-30 Molasses E E E 5 100 Nitric Acid (30% max) F F NR 20 167 Oil, SAE 30 E E E 20 250 Oil, SAE 50 E E E 10-15 250 Oil; Vegetable or Mineral E E E 30 400 Paraffin or Wax E E E 16 Steam E E E 30 300 Steam E E E 25 500 Trichlorethylene F F F 30 150 Water, Distilled E E E 300 212 Water, Tap F E E 300 212 E=Excellent, G=Good, F=Fair, NR=Not Recommended Maximum Watt Density in Still Air Air Temperature F 100 250 500 750 1000 1100 1200 1300 1400 Max Watts/in 2 53 52 50 46 40 35 28 20 13 HotRod Sheath Temperature in 70 F Still Air Watt Density (watts/in 2 ) 5 10 15 20 25 30 35 40 Oxidized Sheath 450 800 1050 1100 1200 1300 1350 1400 Non-Oxidized Sheath 750 1000 1150 1300 1400 1500 1600 1650 Maximum HotRod Watt Density in 200 F Moving Air Air Velocity, Feet per Minute Air Direction 0 500 1000 1500 2000 2500 3000 3500 4000 Parallel to Heater 44 52 56 60 64 67 72 75 78 Perpendicular to Heater 44 68 76 82 86 93 97 103 108 Lead Wire Characteristics Wire Type UL Temperature Rating Maximum Recommended Temperature UL Style No. 300V UL Style No. 600V Comments Ultralead 250 C 450 C 5167 5347 Excellent, durable wire, good for high temperature applications Teflon 250 C 250 C 1815 5191 Good for areas where a small diameter wire is needed. Silicon Rubber 200 C 200 C Good moisture resistance Braided Silicon Rubber 200 C 200 C 3122 3231 Inexpensive wire good for non abrasive applications MGT 450 C 450 C 5334 5335 Good high temperature wire SJO cord 90 C 90 C Rubber jacket, resistant to oil and moisture. For use on 3/8 dia. and larger 7
Wire Diameters Wire Gauge 16 ga 18 ga 20 ga 22 ga 24 ga Conductor Diameter.053.047.038.030.024 300 V Ultralead.112.103.94.088.055 600 V Ultralead.127.118.107.102.N/A 300 V Teflon.079.073.064.056.050 600 V Teflon.085.079.070.062.056 300V Silicon Rubber.115.109.100.092 N/A 300 V Braided Silicon Rubber.106.094.086.078 N/A 300 V MGT.105.093.085.080 N/A 600 V MGT.129.119.109.104 N/A NON-SWAGED CARTRIDGE HEATERS For applications where a swaged heater is not required, non-swaged cartridge heaters offer a cost effective alternative. Non-swaged heaters can be used up to 45 w/in 2 and to temperatures up to 1200 F. Non-swaged heaters offer tighter length tolerances (±1/16 ) than swaged heaters. Non-swaged heaters can be built with 3 independent heat zones. Non swaged heaters are not recommended for applications where there is a lot of vibration or impact. Most of the lead configurations and options available for swaged Hotrod heaters are also available for non-swaged cartridge heaters. Consult your Marathon Heater agent for more information. 1) Standard leads are UL rated to 482 F and can be used up to 850 F. Leads are connected internally with nickel connectors. 2) High temperature cement filling protects leads and internal parts. Epoxy and silicone rubber are also available 3) Nickel-chromium resistance wire stretched evenly through out the heated length. 4) High purity MgO is vibratory filled into the heater for maximum heat transfer. 5) 304 stainless steel sheath for superior oxidation resistance. Welded end disc to prevent contamination and moisture absorption. Maximum Allowable Watt Density For Heating Metals Block Temperature in F Hole Clearance 1000 800 600 400 200 0.003 25 30 35 40 45 0.005 20 25 30 35 45 0.010 20 23 28 30 38 0.015 18 20 25 27 34 0.030 16 15 20 23 30 0.100 10 12 15 20 25 Clearance is determined by taking the hole diameter and subtracting the heater diameter. Watt density is calculated by: Wattage Heated Lth x Diameter x 3.14 Cycling reduces heater life and high cycling applications should use lower numbers. Staying below these values will result in increased heater life. Nominal Minimum Maximum Std. Lead Wire Max amps with Std. Max lead wire Maximum Maximum Volts Diameter Diameter Diameter Gauge Lead wire gauge amps 3/4.742.749 18 15 16 20 600 1.992.999 18 15 16 20 600 Engineering Data Heat Losses From Oil or Paraffin Surfaces in 70 F Air (watts/in 2 ) Temp ( F) Heat Loss 100.2 150.5 200.8 250 1.3 300 1.7 350 2.3 400 2.9 450 3.7 500 4.5 550 5.5 600 6.6 Heat Losses From Water Surfaces in 70 F Air (watts/in 2 ) Temp ( F) 40% Humidity 60% Humidity 80.3.2 90.4.3 100.6.4 110.8.45 120 1.1.6 130 1.4.9 140 1.8 1.2 150 2.4 1.6 160 3 2 170 3.8 2.5 180 4.8 3.1 190 6 3.8 200 7.4 4.8 210 8.8 6 Heat Losses From Molten Metal Surfaces in 70 F Air (watts/in 2 ) Temp ( F) Heat Loss 450 1.5 500 2 550 2.6 600 3.3 650 4 700 4.8 750 5.7 800 6.6 850 7.6 900 8.6 Heat Losses From Vertical Surfaces in 70 F Air (watts/in 2 ) Temp ( F) Oxidized Steel Oxidized Aluminum 100.1.08 200.58.32 300 1.3.7 400 2.2 1.2 500 3.2 1.6 600 4.5 2.2 700 6.3 2.7 800 8.6 3.6 900 12 4.5 1000 16 5.7 1200 26 1400 38 1600 56 Multiply by 1.2 for top surfaces Multiply by 0.8 for bottom surfaces 8
Properties of Metals Material Technical Data Density lbs/in 3 Specific Heat Btu/lb/ o F Thermal Conductivity Btu-in/hr-fe 2 - o F Melting Point F Latent Heat of Fusion Btu/lb Aluminum 0.098 0.24 1488 1220 169 13.1 Antimony 120 Brass Yellow 0.306 0.096 756 1724 11.2 Cadmium 636 Copper 0.322 0.095 2580 1976 91.1 9.8 Gold 0.698 0.032 2030 1945 29 7.9 Incoloy 800 0.29 0.13 80 2500 7.9 Inconel 600 0.304 0.126 103 2500 5.8 Iron, Cast 0.26 0.12 346 2150 6 Lead, solid 0.41 0.032 216 621 11.3 16.4 Lead, Liquid 0.387 0.037 108 - Magnesium 0.063 0.27 1106 1202 160 14 Molybdenum 0.369 0.071 980 4750 126 2.9 Monel 400 0.319 0.11 151 2400 6.4 Nickel 0.321 0.12 396 2642 133 5.8 Nichrome (80% NI-20% Cr) 0.302 0.11 104 2550 7.3 Platinum 0.775 0.035 480 3225 49 4.9 Silver 0.379 0.057 2856 1760 38 10.8 Solder (50% Pb-50% Sn) 0.323 0.051 310 361 17 13.1 Steel, mild 0.284 0.122 312 2570 6.7 Steel, Stainless 304 0.286 0.012 120 2550 9.6 Steel, Stainless 430 0.275 0.11 156 2650 6 Tantalum 0.6 0.035 375 5425 3.6 Tin, solid 0.263 0.065 408 450 26.1 13 Tin, Liquid 0.253 0.052 218 - Titanium 99.0% 0.164 0.13 112 3035 4.7 Tungsten 0.697 0.04 1130 6170 79 2.5 Type metal (85% Pb-15% Sb) 0.387 0.04 500 14+- - Zinc 0.258 0.096 744 786 43.3 22.1 Zirconium 0.234 0.067 145 3350 108 3.2 Properties of Non-Metallic Solids Thermal Expansion In/in/ o Fx10-6 Material Density lbs/in 3 Specific Heat Btu/lb/ o F Thermal Conductivity Btu-in/hr-fe 2 - o F Melting Point F Latent Heat of fusion in/in/ o F Thermal Expansion In/in/ Fx10-6 Asbestos cement board 0.07 0.025+- 5.2 Asphalt 0.076 0.4 5.3 Boron Nitride 0.082 0.33 125 5430 Brickwork 0.076 0.22 3.-7. 3-6 Carbon 0.08 0.28 165 6700.3-2.4 Cellulose Acetate 0.047.3-.5 1.2-2.3 61-83 Glass 0.101 0.161 6 5 Graphite 912 - Ice 0.0324 0.53 11 32 144 28.3 Mica 0.102 0.21 3 18 Mgo (Compacted) 0.112 0.209 20 7.7 Nylon 0.04 0.4 1.5 61-83 Paper 0.034 0.45 0.82 Paraffin 0.032 0.69 1.6 133 63 Phenolic, general purpose 0.046 0.4.6-1.2 44-61 Polyethylene 0.035 0.55 2.3 94 Polystyrene 0.038 0.32.7-1. 33-44 Rubber 0.044 0.44 1.1.340 Sand.0637 10.8 Steatite 0.094 0.2 17.5-23 4.5-5.5 Sulfur 0.075 0.175 1.9 246 17 36 Teflon 0.078 0.25 1.7 55 Vinyl 0.046.3-.5.8-2 28-100 Wood, oak 0.030 0.57 1.4 Properties of Gasses Gas 3 Density, lbs/ft Specific Heat Btu/lb/ o F Thermal Conductivity Btu-in/hr-ft 2 - o F Air at 80 degrees 0.073 0.24 0.18 Air at 400 degrees 0.046 0.245 0.27 Ammonia 0.044 0.523 0.16 Argon 0.102 0.125 0.12 Carbon dioxide 0.113 0.199 0.12 Carbon monoxide 0.072 0.248 0.18 Chlorine 0.184 0.115 0.06 Helium 0.011 1.25 1.1 Hydrogen 0.0052 3.39 0.13 Nitrogen 0.072 0.248 0.19 Oxygen 0.082 0.218 0.18 Sulphur dioxide 0.172 0.152 0.07 Water vapor at 212 degrees F 0.037 0.482 0.16 9
Properties of Liquids Liquid Density lbs./ft 3 Specific Heat Btu/lb o F Thermal Conductivity Btu-in/hr-ft 2 - o F Boiling Point o F Heat of vaporization Btu/lb Acetic acid, 20% ** 64.1 0.91 3.7 214+- 810+- Alcohol (ethyl) 49.6 0.6 1.3 173 367 Brine (25% NaCI)** 74 0.81 4 221+- 728+- Caustic Soda (18% NaOH)** 74.9 0.84 3.9 221+- 795+- Dowtherm A 66.1 0.44 0.96 496 42.2 Freon 12 82.7 70 psig 0.23 0.67-21.6 62 Glycerine 78.7 0.61 2 556 Hydrochloric acid 10% 66.5 0.93 3.9 221 NaK (78%K) 46.2***.21*** 167 1446 Nitric acid, 7% 64.7 0.92 3.8 220+- 918+- Oils (petroleum) 58.2 0.43 1 Paraffin (melted) 47.1+-.71+- 1 Potassium (K) 44.6***.18*** 320 1400 893 Sodium (Na) 51.2***.30*** 580 1621 1810 Sulfuric Acid 10% 74 0.92 4 216 Therminol FR-2 90.6 0.3 0.7 648+- Turpentine 54.3 0.41 0.9 318 123 Vegetable Oil 57.5.43+- 1.1 Water 62.3 1 4.2 212 970 *At or near room temperature ** Percent concentration by weight of H2O solution *** At 1000 degrees F Kilowatt-Hours Required to Heat Steel Lbs. Of Temperature Rise F Steel 50 100 200 300 400 500 600 25 0.06 0.12 0.25 0.37 0.5 0.65 0.75 50 0.12 0.25 0.5 0.75 1 1.25 1.5 100 0.25 0.5 1 1.5 2 2.5 3 150 0.37 0.75 1.5 2.25 3 3.75 4.5 200 0.5 1 2 3 4 5 6 250 0.65 1.25 2.5 3.75 5 6.25 7.5 300 0.75 1.5 3 4.5 6 7.5 9 400 1 2 4 6 8 10 12 500 1.25 2.5 5 7.5 10 12.5 15 600 1.5 3 6 9 12 15 18 700 1.75 3.5 7 10.5 14 17.5 21 800 2 4 8 12 16 20 24 900 2.25 4.5 9 13.5 18 22.5 27 1000 2.5 5 10 15 20 25 30 Kilowatt-Hours Required to Heat Water Amount of Liquid Temperature Rise F Cubic Ft Gallons 20 40 60 80 100 120 140 0.66 5 0.3 0.5 0.8 1.2 1.6 2 2.7 1.3 10 0.5 1.1 1.6 2.4 3.2 4 5.3 2 13 0.8 1.6 2.4 3.6 4.5 5.7 7.2 2.7 20 1.1 2.2 3.2 4.8 6 7.5 9.5 3.3 25 1.3 2.7 4 6 7.5 9.5 12 4 30 1.6 3.2 4.8 7 8.8 11 14 5.3 40 2 4 6 9 12 15 20 6.7 50 2.7 5.4 8 12 15 19 24 8 60 3.3 6.4 9.6 14.5 18 23 29 9.4 70 3.7 7.5 11 17 21 26 33 10.7 80 4.3 8.5 13 19 24 30 38 12 90 5 10 14.5 22 28 35 44 13.4 100 5.5 11 16 24 30 38 48 16.7 125 7 13 20 30 38 48 60 20 150 8 16 24 36 45 57 72 23.4 175 9 18 28 42 53 67 85 26.7 200 11 21 32 48 60 75 95 33.7 250 13 27 40 60 75 95 120 40 300 16 32 47 70 88 110 140 53.4 400 21 43 64 96 120 150 190 66.8 500 27 53 80 120 150 190 240 Max Time, Hours. 10 10 7 5.5 5 4 3.5 Add 5% for uninsulated tanks. 10
Conversion Factors Work btu gm-cal watt-hr ft-lb 1 252 0.2928 778.2 0.003968 1 0.001162 3.086 3.413 860.5 1 2656 0.001286 0.3241 0.0003766 1 Power btu/hr watts horsepower ft-lbs/min 1.2931 0.0003929 12.97 3.412 1 0.001341 44.27 2546 745.7 1 33000 0.07716 0.02260 0.00003030 1 Heat Flux btu/hr-ft 2 - F/ft gm-cal/sec-cm 2 watts/cm 2 watts/in 2 1 0.00007535 0.0003154.01313 13272 1 4.187 27.013 3170.2388 1 6.451 491.4 0.037014 0.1550 1 Thermal Conductivity btu/hr-ft 2 F/ft gm-cal/sec-cm 2 - C/cm watts/cm 2 - C/m kg-cal/hr-m 2 - C/m 1.004134.01731 1.488 241.9 1 4.187 360 57.79.2388 1 86 0.672 0.002778 0.01163 1 Coefficient of Heat Transfer btu/hr-ft 2 - F gm-cal/sec-cm 2 - C watts/cm 2 - C kg-cal/hr-m 2 - C 1 0.0001355 0.0005678 4.882 7373 1 4.187 36000 1761.2388 1 8600 0.2048 0.00002778 0.0001163 1 Length cm meter km in ft mile 1.01 0.00001.3937 0.03281 6.214 x 10-6 100 1.001 39.37 3.281 0.006214 100,000 1000 1 39,370 3281 0.6214 2.54 0.0254 2.54 x 10-5 1.08333 1.578 x 10-5 30.48 0.3048 0.0003048 12 1 0.0001894 160,930 1609 1.609 63360 5280 1 Temperature Conversion Chart F C -100-73 -58-50 -50-46 0-18 10-12 20-7 32 0 40 4 50 10 60 16 68 20 70 21 80 27 86 30 90 32 100 38 104 40 125 52 140 60 150 66 167 75 175 79 200 93 F C 212 100 250 121 300 149 302 150 347 175 350 177 392 200 400 204 450 232 482 250 500 260 550 288 572 300 600 316 650 343 662 350 700 371 750 399 752 400 800 427 842 450 850 454 900 482 F C 932 500 950 510 1000 538 1022 550 1050 566 1100 593 1112 600 1150 621 1200 649 1292 700 1300 704 1382 750 1400 760 1472 800 1500 816 1600 871 1652 900 1700 927 1800 982 1832 1000 1900 1038 2000 1093 11
Air Heaters Marathon manufactures a line of 1/2 diameter air heaters. These heaters are used extensively in the heat staking industry and for plastic welding. Temperature Controllers Marathon carries a variety of microprocessor based temperature controllers for all applications and price ranges. Mica Band Heaters Marathon manufactures mica band heaters and nozzle heaters in a variety of sizes and configurations. We also stock a large variety of nozzle heaters for immediate delivery. Thermocouples Type J and type K thermocouples are available with stainless braid or flexible stainless hose. Thermocouples can be terminated with a variety of connectors. MARATHON HEATER 808 Hackberry Lane HCR 3, Box 86E Del Rio, Texas 78840 (830) 775-1417 FAX (830) 775-4379 www.marathonheater.com