Thick Film Tubular Water heater
Electric Thick Film Heating Circuit can be sintered and covered with 5 insulation layers on the surface of Stainless Steel Tube to instant heating flowing water inside of tube. It can get 95℃ Boiling Water in flow rate 480ml-600ml/Minute.Thick film Tubular heater is applied in Flowing Liquid Instant Heating. Due to its long service time, higher heat transfer and compact profile, It's the ideal heating element to replace immersion water heating elements.
Advantages of thick film heating tube
1, Safe and durable high strength: Stainless steel substrate, Multi-layer microcrystalline vitreous insulation.
2, Fast heating: heating circuit has temperature rise over 80~150 degrees per second.
3, High utilization rate of heat: directly rapid-heat Stainless steel tube, a big heat exchange area, fast replacement, efficiency up to above 98%.
4, Green and environmental protection: pure resistive load, no electromagnetic radiation, good for human body.
-10% - +5%
Stainless steel thick film heating tube, can be used for instant electric faucet, water heater, micro water heater, electric heating Faucet, water dispenser accessories, hot water machine, hot water dispenser, water purifier heating, Heating body, integrated machine heating element, heating tube, coffee machine heating tube, heater, metal heating tube.
To Order, Please specify your detail required specifications. All the Thick Film Electric Heating Tubes are be made customized as the actual design of our customer’s indicidual specific requirements.
ESL recommends that the thickness of all 29XXX resistor pastes after sintering be 10-12 microns to ensure that the power density is above 60 watts per square centimeter.
ESL recommends a thickness of 10-12 microns after sintering to ensure that the current density of the resistance element is 3 amperes per millimeter.
The material used in the thick film heater has a high TCR, so the difference between the resistance value at room temperature and operating temperature must be considered.
For example, a customer requires that the heating element can support 3000 watts at 240 volts alternating current, and the maximum temperature is controlled at 150 °C. The area available for printing is a 120 mm diameter substrate.
V = I x R Ohm’s Law
Power = voltage x current
Temperature coefficient = ((RH-RC) x 106) / (RC x (TH-TC))
Here: RH=resistance value at working temperature; RC=resistance value at the beginning
TH = maximum temperature, °C; TC = initial temperature, °C
ESL 29115 was selected for this calculation
Power at operating temperature 3,000 = 240 x current
Current = 12.5 A
The width on the 3 A/mm resistor pattern is about 4 mm. (12.5A/ 3A per mm = width 4.17 mm)
The resistance of the resistor at working temperature is 240 / 12.5 = 19.2Ω
The TCR of the material is 1,500 ppm/°C
So: 1,500 = ((19.2-RC) x 106) / (RC x (150-25))
(1,500 x (150-25) x RC) / 106 = (19.2- RC)
0.1875 RC = 19.2-RC
1.1875 RC = 19.2
RC = 16.17Ω
In order to achieve the resistance value of 16.17Ω at room temperature, a 162 square trace is required. The width of the track is 4 mm, so the length is 648 mm. The total area of the track is 2592 square millimeters. The rated power is 3000 watts, so the power density is 115.7 watts per square centimeter. This value is too high, especially the power at the moment of opening. In this way, it is necessary to increase the area to ensure safety. This requires a track with a width of 5.5 mm and a length of 890 mm to achieve the appropriate resistance (using 29115). The current area is 49 square centimeters, compared to the power density of 61 watts per square centimeter. This is already a safe power density. The change in resistance after sintering the upper glass protective glaze is not calculated. The power at the moment of opening is 3562 watts, which is 72.7 watts per square centimeter in a short period of time.