Inert Baking
Inert baking ovens cure parts in a low-oxygen environment, filling the oven with nitrogen or another gas. For certain Carbon resins, inert baking offers advantages over standard air baking.
For applications with rigid materials that require great toughness to pass functional testing, baking parts in a low-oxygen environment significantly improves toughness while retaining other desired characteristics. When rigid parts are baked in an inert oven:
- Elongation at Break improves +60% for EPX 82 and +57% for EPX 150.
- Unnotched Charpy improves by +200% for EPX 82 and +90% for EPX 86FR.
- Unnotched Izod Impact Strength improves +33% for EPX 150.
For elastomeric applications using EPU 44 or EPU 46, inert baking improves color accuracy and enables baking larger batches of parts. See EPU 46 Baking Considerations for more information.
For detailed information on inert bake performance properties, see the following Technical Data Sheets:
Rigid Resins
Elastomeric Resins
Carbon has evaluated and recommends the following inert ovens:
If you choose to use a different inert oven from the ones recommended by Carbon, please ensure that the oven meets the specifications listed in this section.
Description | Specification |
|---|---|
O2 Concentration | Must be able to achieve 500 ppm or less |
Power Supply | 50-60 Hz (see table below) |
Ventilation | 3" or 4" exhaust port with damper with vent duct connected to exhaust port in accordance with local code regulations |
Cooling | Cooling with water coil |
Set Point Temp Variability | plus/minus 1° C |
Turnover Airflow per Volume | 9 min for 9.0. scf oven 1.6 min for 5.8 scf oven * Will be dependent on oven size |
Overhead Safety Temperature | >250° C |
Temperature Range | 15 C above ambient to >250° C |
Inert Gas Supply | 40 to 80 PSIG, 20 to 200 SCFH |
Seal Type | Gasket (bellofram can extruded this material is different dimensions): Bellofam silicone 5104-NSF Sealant: Permatex 24105 |
Please see below for the maximum oven load based on the suggested flow rates for recommended oven solutions. The suggested flow rates are highlighted below for the Blue M DIC-256 (30 scfh) and for the Blue M DIC-296 (60 scfh). If using a different oven, please refer to the corresponding maximum oven load rate that best matches your rate of exhaust air flow.
Rate of exhaust air flow | Rate of exhaust air flow | Maximum Oven Load for Average Part Thickness of 1.0 mm | Maximum Oven Load for Average Part Thickness of 2.5 mm |
|---|---|---|---|
scfh | scfm | g | g |
30 | 0.5 | 505 | 1173 |
45 | 0.8 | 758 | 1759 |
60 | 1.0 | 1010 | 2345 |
75 | 1.3 | 1263 | 2931 |
100 | 1.7 | 1684 | 3907 |
150 | 2.5 | 2526 | 5861 |
200 | 3.3 | 3368 | 7814 |
Manufacturer document that contains safety, installation, operation and maintenance information.
The oven must be programmed for the specific resin you are using. Carbon provides baking profiles (also called baking programs) below:
EPU 44, EPU 46
EPX82, EPX 86FR
EPX150
Download the desired profile onto a USB drive and import the program directly from the drive into your oven.
Step 1
Insert a USB Drive containing the oven program into the USB port of the oven.
Step 2
Go to the Oven Display and touch the Menu button to open the Main Menu.
Step 3
From the Main Menu, touch Profiles to open the list of existing profiles.
Step 4
From the profile list, touch Options to display the profile options.
Step 5
From the options list, touch Import File to open the File Transfer screen.
Step 6
From the File Transfer screen, touch Import to open the list of Import options.
Step 7
From the options list, touch PROFILE to display the list of oven profiles on the USB drive.
Step 8 From the file list, touch the desired program (in this example EPX82-86FR.wpf) to start importing the profile. A progress bar appears, displaying the progress of the import.
Step 9
When the program finishes loading, touch the Hide button to close the progress bar.
Step 10
From the File Transfer screen, touch the Done button to view the list of profiles (program files) available on the oven.
Step 11
The program that was just imported appears at the end of the profiles list. Depending on the number of files, you may need to scroll the list to see that EPX82-86FR (the file imported in this example) appears at the end of the list.
This operation section describes:
- Bake Setup
- Preparing for Bake
- Starting a Bake
- Terminating a Bake in Progress
- Oven Cool Down
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- Load trays onto racks in the oven.
- Close and latch the door.
Step 1
Ensure that the SCFH AIR flowmeter is at 60 (as seen in the image at right). This is a manual dial, in case it is not at 60, it will need to be adjusted using the larger star-shaped knob below the meter.
Step 2
Ensure that the Chamber Pressure (second image) should be at 0 inches.
Step 1
On the oven touchscreen, touch the Menu button to open the MAIN Menu.
Step 2
From the MAIN Menu, touch Profiles to open the list of existing profiles.
Step 3
From the list of profiles, find the bake profile you want to run, and touch Actions button for the bake profile (in this example it's EPX82-86FR). You may need to scroll down to see the profile.
A Popup opens.
Step 4
From the Popup, touch Run Profile to start the bake.
The Popup closes and returns you to the main screen.
Step 5
On the main screen, the Status area in the top left displays a green clock, the name of the profile (in this example EPX82-86FR), and the time remaining in the bake cycle.
At this point, check that the SCFH AIR flowmeter is still at 60 scfh and that the Chamber Pressure is between 1-2 inches.
Step 1
To stop a bake in progress, from the main screen, touch the Profile Actions button.
A Popup opens.
Step 2
From the Popup, touch Terminate.
The Popup closes.
On the main screen, the Status area in the top left displays a red clock, and there is no remaining time showing. The oven automatically starts its cool down process. See Oven Cool Down below.
- Once the bake is complete, the main screen displays a red clock in the status area in the top left.
- The oven automatically begins cooling.
- When the oven temperature is below 50° C, touch On/Off Event 1 and Cooling Event 2 on the touchscreen to turn off oven circulation and cooling.
- Open the oven door gently/slowly. You can now remove the parts.
- Leave the oven door open after bake. The flowmeter can be left on. The chamber pressure will drop to 0.
This maintenance schedule applies to the Blue M oven. For additional information, refer to the Blue M oven manual above.
- Inspect interior for debris.
- Inspect door gasket and ensure that the door closes securely. Clean gasket as needed.
- Inspect door gasket for any wear, cracks, tears, or any damage to the gasket.
- Check that the door seals evenly around its perimeter to negate heat loss. Adjust door latches if necessary.
- Check/adjust chamber pressures (purge flow + run flow).
- Clean the oven’s Interior.
- Swap or clean the check valve (if equipped).
- Check N2 flow meters (if equipped) adjust or replace if necessary.
Calibrate temperature.
Manufacturer document that contains safety, installation, operation and maintenance information.
The oven must be programmed for the specific resin you are using. Carbon provides baking profiles (also called baking programs) below:
EPX 82, EPX 86FR
Download the desired profile onto a USB drive and import the program directly from the drive into your oven.
Step 1
Insert a USB Drive containing the oven program into the USB port of the oven.
Step 2
On the oven Controller, touch the Home button in the top left corner to open the MAIN screen.
Step 3
From the MAIN screen, touch PROG SET to open the list of existing programs.
Step 4
From the List of Programs, touch NEW to open a Popup to enter a new program number.
Step 5
The Popup automatically displays the next program number. In this example the next available program number is 3. Touch OK to accept the New Program Number and close the Popup. The default program name of PROG-003 is assigned to the file.
Step 6 Touch ... on the PROG-003 line to display the options screen.
Step 7
From the Options screen, touch IMPORT FROM UDISK to display the list of files of the USB drive,
Step 8
From the file list, touch the desired program (in this example EPX82-86FR.bin) and then touch the Enter Arrow (bottom right corner) to start importing the program.
A progress bar displays the progress of the program import.
Step 9
When the program finishes importing, the list of programs includes the new program (in this example PROG-003 on line 3). Touch the Return Arrow button (bottom right corner) to display the MAIN menu.
Step 10
To confirm that the program file imported properly, touch the PROG SET button to open the program list.
Step 11
In the program list, you will see that the imported program is now set to a new filename (in this example, EPX82 - 86FR on line 3), which indicates the resin(s) that the program applies to.
This operation section describes:
- Starting a Bake
- Terminating a Bake in Progress
For additional operation information, refer to the Yuanyao Product Manual above.
Step 1
Load trays onto racks in the oven, and close and latch the door.
Step 2
From the Controller, touch the Home icon (in the top left corner) to open the MAIN screen.
Step 3
From the MAIN screen, touch PROG SET to open the list of programs.
Step 4
From the List of Programs, touch ... in the right column of the Program you want to run (in this example EPX82 - 86FR in row 3). This opens the Options screen.
Step 5
From the Options screen, touch START THIS PROG, This opens a Popup.
Step 6
From the Popup, touch OK to start running the bake program. The popup closes.
The top of the screen indicates that the selected program is running. In this example: EPX82 - 86FR RUNNING.
Step 7
Check the Flow meter to ensure that the nitrogen flow is between 40-45 LPM and the Differential pressure gauge is between 100-250 pascals.
Step 1
From the MAIN screen, touch OPER. SCR to open the MONITOR screen.
Step 2
From the MONITOR screen, touch the STOP button on the bottom right corner. This opens a Popup.
Step 3
From the Popup screen, touch the STOP button. The popup closes.
The top left of the screen displays PROG STOP, indicating that the program has stopped running.
When a bake in progress is terminated, the oven does not initiate cooling. However, the oven will gradually cool down.
When the oven temperature gets below 50° C, you can open the oven door.
Step 1 From the MAIN screen, touch OPER. SCR to open the MONITOR screen.  Step 2 From the MONITOR screen, touch the STOP button on the bottom right corner. This opens a Popup.  Step 3 From the Popup screen, touch the STOP button. The popup closes.  The top left of the screen displays PROG STOP, indicating that the program has stopped running. When a bake in progress is terminated, the oven does not initiate cooling. However, the oven will gradually cool down. When the oven temperature gets below 50°, you can open the oven door.
Yuanyao Oven For additional information, refer to the Yuanyao oven manual above.
- Inspect interior for debris.
- Inspect door gasket and ensure that the door closes securely. Clean gasket as needed.
- Inspect door gasket for any wear, cracks, tears, or any damage to the gasket.
- Check that the door seals evenly around its perimeter to negate heat loss. Adjust door latches if necessary.
- Check/adjust chamber pressures (purge flow + run flow).
- Clean the oven’s Interior. Semi-annual (6 months):
- Swap or clean the check valve (if equipped).
- Check N2 flow meters (if equipped) adjust or replace if necessary.
- Calibrate temperature.
Cryogenic liquids are liquefied gases that are kept in their liquid state at very low temperatures.
- Cryogenic fluids are stored and used in special, thermally insulated containers, like this dewar.
Liquid nitrogen is a cryogenic liquid that can be used in the inert bake process.
- At a minimum, wear protective cryo (thermal) gloves and a face shield when connecting and transferring liquid nitrogen.
When working with cryogens, follow these guidelines:
- verify that pressure relief devices are in place and functioning properly
- if valves have snowballs accumulating do not use force to dislodge the ice
- if the pressure gauge is rising unexpectedly, have the pressure relief devices checked
- use smallest sized dewar possible for a given job
- use good lifting practices
- ensure that two employees move dewars, not one
- secure dewars (empty or other) with straps to prevent tip-over during an earthquake
When transferring liquid nitrogen from a large dewar into a transport dewar, ensure a diffuser is used.
At this time we recommend baking EPX 82 or EPX 86FR in this oven through either air or inert bake schedules. A potential fire risk exists if you operate your oven at temperatures in excess of the Carbon recommended bake profiles.
See more information about LMA in Thermal Curing.
For questions and support related to inert baking parts made with Carbon resins, please contact Carbon Support.
Blue M 2821 Old Route 15 New Columbia, PA 17856 USA +1 570 538 7200
For Questions and Support for the oven hardware or software, please contact:
Yuanyao
No.5, 3rd Street, Yinsha Road, Xiabian Community, Chang'an Town, Dongguan city, Guangdong, 523876. China +86-13532971605
+1 800 586 2473