Active Member
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[China]
Address: 69 gongxin qiao road, xinba, yangzhong city, zhenjiang city, jiangsu province, China
Contact name:Chen Yumin
Jiangsu Gaoyi Electric Technology Co.,Ltd |
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Steam Heating Element Immersion Electrical Heater
Description of fin tube steam heaters:
In applications where tubular heaters are exposed to forced convection, placing fins around tubular heaters increases their surface area and thus improves their heat transferring capacity. Finned tubular heaters, compared to regular tubular heaters, run at lower surface temperatures for the same watt densities when placed in identical air streams. Graph1 compares watt density, outlet air temperature, and the speed of air flow for regular and finned tubular heatersrespectively. Despite their advantages, finned tubular heaters are not recommended for applications where outlet air temperatures exceed 600°F.
The physical characteristics of a finned tubular heater play a major role in the effectiveness of its heat transfer. The table below specifies the outside diameter of fins, their thickness, the spacing between consecutive fins, as well as the element sheath and fin material.
Application of fin tube steam heaters:
Dryers
Recirculation ovens
Fan-forced heaters
Heat treating and annealing
Construction of fin tube steam heaters:
The sheath material of a fin tube steam heater and its watt density are critical factors that affect its durability. The standard finned tubular heaters are made of steel sheath and steel fins (750°F maximum surface temperature) since steel is very efficient in heat transfer. Finned tubular heaters have a plain-surface finish. For corrosive environments or high-temperature applications (above 750°F), finned tubular heaters can be made with stainless steel sheath and stainless steel fins.
Watt densities of fin tube steam heaters:
Safe watt densities that keep surface temperatures below allowable limits depend on the speed of the incoming air and its outlet temperature.
Physical characteristics of finned tube heating element:
The outside diameter of fins, their thickness, the spacing between consecutive fins, and the element sheath and fin material all play a major role in the effectiveness of heat transfer.
| Tube diam. | Fin thickness | Fins per inch | Fin width | Total in² per linear inch* | Max. sheath length* | Outside diam. of fins |
| 0.216" | 0.020" | 5 | 0.375" | 8.30" | 240" | 1.01" |
| 0.315" | 5 | 9.20" | 1.07" | |||
| 0.375" | 5 | 10.10" | 1.13" | |||
| 0.430" | 5 | 10.83" | 1.18" | |||
| 0.475" | 5 | 11.60" | 1.23" | |||
| *Dimensions are subject to change | ||||||
Optional features of fin tube steam heaters:
Mounting attachments of fin tube steam heaters:
Threaded fittings, if required, are the standard mounting attachments supplied with finned tubular heaters. These fittings are brazed or crimped onto the heaters. For special applications, finned tubular heaters can be made with mounting brackets that have special designs.
