The element terminal holes in the furnace walls must be in line and be large enough in size to prevent the element or terminal tube from being pinched at all furnace temperatures. Terminal tubes are optional but recommended for use with the SER and TSR elements and with fiber wall furnaces. Some furnaces have a potential problem of electrical conduction to ground. The ceramic terminal tubes have superior electrical resistance properties and can prevent this from occurring.

The tubes protect the furnace wall insulation and provide a constant clearance. They also are recommended in applications where product vapors may condense in the furnace terminal holes. This can cause the element to stick to the wall. When sticking the element may break from mechanical forces caused by thermal expansion and contraction. The tubes can prevent this from occurring, for if the element sticks to the tubes, the tubes can move.

When vapors depositing on the elements are a problem it is recommended that ceramic fiber pads be placed beneath the element cold ends and the terminal tubes where they enter the furnace.

Tucking ceramic fiber around the circumference of the element where it enters the terminal hole is also recommended to reduce heat losses from radiation and convection.

Standard Sizes
Terminal tubes are available for Starbar diameters 1/2" (13 mm) through 2-1/8" (54 mm) in a standard length of 4-1/8" (105 mm). Longer lengths available upon request.

Category:

Sizing Breakdown

Item #Starbar DiameterTube Outer DiameterTube Inner DiameterTube Overall LengthCollar DiameterCollar Thickness
2024-1-130.50 Inch
13 mm
1.37 Inch
35 mm
0.81 Inch
20 mm
4.12 Inch
105 mm
2.00 Inch
50 mm
0.38 Inch
10 mm
2024-1-160.63 Inch
16 mm
1.37 Inch
35 mm
0.81 Inch
20 mm
4.12 Inch
105 mm
2.00 Inch
50 mm
0.38 Inch
10 mm
2024-3-190.75 Inch
19 mm
1.75 Inch
44 mm
1.18 Inch
30 mm
4.12 Inch
105 mm
2.38 Inch
60 mm
0.38 Inch
10 mm
2024-3-220.88 Inch
22 mm
1.75 Inch
44 mm
1.18 Inch
30 mm
4.12 Inch
105 mm
2.38 Inch
60 mm
0.38 Inch
10 mm
2024-5-251.00 Inch
25 mm
2 Inch
51 mm
1.44 Inch
37 mm
4.12 Inch
105 mm
2.75 Inch
70 mm
0.38 Inch
10 mm
2024-5-321.25 Inch
32 mm
2 Inch
51 mm
1.44 Inch
37 mm
4.12 Inch
105 mm
2.75 Inch
70 mm
0.38 Inch
10 mm
2024-7-351.38 Inch
35 mm
2.25 Inch
57 mm
1.69 Inch
43 mm
4.12 Inch
105 mm
3 Inch
75 mm
0.38 Inch
10 mm
2024-7-381.50 Inch
38 mm
2.25 Inch
57 mm
1.69 Inch
43 mm
4.12 Inch
105 mm
3 Inch
75 mm
0.38 Inch
10 mm
2024-9-441.75 Inch
44 mm
2.50 Inch
64 mm
1.94 Inch
49 mm
4.12 Inch
105 mm
3.25 Inch
83 mm
0.38 Inch
10 mm
2024-11-542.12 Inch 54 mm3.00 Inch 76 mm2.44 Inch 62 mm4.12 Inch 105 mm3-3/4 Inch 95 mm0.38 Inch 10 mm

Specifications

Note

Special OD, ID and Overall lengths available upon request.

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