GFSeries

Silicon Carbide Element Electric Floor Standing Box Furnaces 2800°F (1535°C)


Type Medium Box
Power Source Electric
Loading Front
Uniformity AMS Class 5 (± 25ºF / 14ºC)
Atmosphere Air
Lining Brick w/ Fiber Roof

Applications

Description

The GF SERIES Electric Furnaces feature 2800°F (1535°C) operation. Silicon carbide elements are controlled with a phase angle fired SCR. The door features a deep plug for minimal heat loss around the door. Because this door must be opened horizontally the furnace can not be loaded and unloaded easily at high temperatures. These furnaces are excellent for long high temperature cycles. They are used mostly in ceramics but find application in chemical processing and other fields.


Processes


Markets

Standard Model Sizes

Our most popular model sizes are listed below. Discuss a custom solution that fits your exact needs by contacting our sales team today.
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LOCKED BY MODEL
Model
#
Working Dimensions
W
H
D
Outside Dimensions
W
H
D
Std Power
(kW)
Max Load
(Lbs)
Ship Weight
(Lbs)
GF9
12
8
10
66
54
36
10 50 1400
GF29
12
8
20
66
54
46
20 100 1800
GF39
12
8
30
66
54
56
30 125 2000
GF524
15
15
24
69
61
50
33 150 2200
GF814
18
12
24
73
58
50
34 150 2200
GF824
18
18
24
73
64
50
41 150 2700
GF836
18
18
36
73
64
62
52 225 3400
GF236
24
18
36
79
64
62
60 300 4100
GF244
24
24
24
79
70
50
54 200 3900
GF246
24
24
36
79
70
62
66 300 4300
GF248
24
24
48
79
70
74
86 400 5900
GF3636
36
36
36
91
82
62
106 450 7400
GF3648
36
36
48
91
82
74
127 600 8600
GF3672
36
36
72
91
82
98
164 900 10000

Additional Features

DEEP PLUG DOOR WITH VESTIBULE AND DOUBLE PIVOT HINGE FOR EXTREMELY TIGHT SEAL
The horizontally opening door features a 2” deep plug for excellent heat blockage even at elevated temperatures. Double pivoting of hinge allows parallelogram opening of the plug door. This keeps the hot face from the operator and allows tight sealing of the door. A vestibule around the perimeter of the door reduces heat loss when the door is opened. This also aids temperature uniformity while protecting the elements from physical damage.
1-1/2” THICK SILICON CARBIDE HEARTH
The hearth is a 1-1/2” thick silicon carbide hearth plate for strength and excellent heat transfer. Height from floor to hearth is 32”.
DIGITAL PID CONTROL AND HIGH LIMIT SYSTEM
The standard control is a Honeywell UDC 2500 digital PID 3 mode tuning control. All fuses, contactors, and controls are located in a NEMA 1 panel. The thermocouples are Type R. The control voltage is transformed to 120 volts. A NEMA 13 Lighted On/Off switch and NEMA 13 door power cut off switch are included. A Honeywell UDC 1200 digital high limit back up control with manual reset, back up contactors and separate thermocouple is standard. Customer must connect fused power supply to single point on panel.
SCR POWER CONTROL AND TAP TRANSFORMER
The power control has a 6 position tap transformer with taps that are changed inside the control panel and a phase angle fired SCR. The SCR adjusts for most voltage changes automatically as needed, eliminating the need to manually change taps during operation.
TEMPERATURE UNIFORMITY OF +/-25F (+/-15C)
Uniformity of +/-25F (+/-15C) is normal above 1600F (870C) within 2/3 of the working dimensions.
TESTING AND INSTRUCTIONS
The furnace is tested to insure circuit integrity. A complete instruction manual includes easy start up instructions, theory of operation, maintenance instructions, parts list, and a detailed trouble shooting guide. A ladder logic diagram and panel layout are prepared on CAD for easy readability.
WARRANTY
The furnace is warranted for one year except for elements and thermocouples which are warranted for six months. See warranty sheet Q12W.
MULTILAYERED INSULATION; CERAMIC FIBER ROOF AND DOOR PLUG
There is 4-1/2” of 3000F (1650C) insulating firebrick backed up with 4” of 2300F (1260C) ceramic fiber. The roof and door are made from 2850F (1565C) ceramic fiber modules. All insulation is available in preshaped sections for easy maintenance. As an option the entire insulation can be ceramic fiber modules for fast heat up and cool down. No asbestos is used.
SILICON CARBIDE HEATING ELEMENTS
Silicon carbide heating elements are mounted over and under the hearth for even heating. All element connections are on the sides. Watt density is between 30 and 39. Elements are rated for 3000F (1650C).
FLOOR STANDING CASE CONSTRUCTION
The case is reinforced 10 gauge and 3/16” sheet steel with an integrated floor stand and lifting rings. The entire case is primed with 800F silicone paint and finished in machine enamel.

Additional Options

CONTROL, RECORDER AND ELECTRICAL OPTIONS
CONTROL, RECORDER AND ELECTRICAL OPTIONS
HIGH DENSITY SILICON CARBIDE ELEMENTS
These will provide greater element life than the standard silicon carbide elements, especially in atmosphere applications.
INERT ATMOSPHERE CONTROL FOR FURNACES WITH SILICON CARBIDE ELEMENTS
The GF and GLF furnaces can be fitted for use with inert or combustible atmospheres. Inlet of the atmosphere is through the element connection chamber to maintain cool element connections. This system includes special all aluminum element hardware inside the sealed boxes. The door features a special tadpole gasket. A completely piped flowmeter and regulator with ball valve, pressure gauge and pressure relief valve is included. Complete safety systems for use with combustible atmospheres are available. Temperature is limited to 2500F (1370C) with nitrogen, to 2200F (1200C) with any hydrogen over 4% but can take the full rated temperature with argon.
JIC CONTROL OPTION
This includes a NEMA 12 control cabinet, all oil tight switches and a panel mounted fused disconnect switch. Zone switches if included are percentage timers.
MOTOR DRIVEN VENTURI SYSTEM
A motor driven venturi vent system is available. This system exhausts air out of the furnace and pulls in fresh air. Air inlets are located per customer specifications. (NOTE: venturis work by blowing air past a tube that is inserted into the furnace. This creates a vacuum without blowing cold air into the furnace. It has the advantage of having a controlled exhaust and minimizing heat shock in the furnace.) A 1 H.P. motor, complete with motor starter, drives the system. Capacity is 300, 600 or 1250 CFM, depending on the size of unit ordered. A stack should be installed to exhaust the hot air. Normally, a hand operated stainless steel damper is provided with the venturi system to control the amount of air being exhausted from the furnace.

Downloads

Brochure For GF