Inert Baking

overview 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 docid\ x4zriehw1jrxse lbqyof for more information technical data sheets for detailed information on inert bake performance properties, see the following technical data sheets rigid resins https //docs carbon3d com/files/technical data sheets/tds carbon epx 82 pdf https //docs carbon3d com/files/technical data sheets/tds carbon epx 86fr pdf https //docs carbon3d com/files/technical data sheets/tds carbon epx 150 pdf elastomeric resins https //docs carbon3d com/files/technical data sheets/tds carbon epu 46 pdf https //docs carbon3d com/files/technical data sheets/tds carbon epu pro 50 90 black pdf recommended inert ovens carbon has evaluated and recommends the following inert ovens https //www yuanyao tech com/ https //www bluem com/products/mechanical convection ovens/146 series inert gas mechanical convection oven inert oven specifications 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) https //www belloframsilicones com/silicone products/5104 nsf certified closed cell silicone sponge extruded astm d 1056 2d1 sealant https //www amazon com/dp/b001revark?ref =pe 1815430 211938580\&th=1 maximum oven load recommendations please see below for the maximum oven load based on the flow rate of your inert oven 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 blue m oven product manual refer to the product manual for the specific model you are using baking profiles 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 import an oven program 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 operation this operation section describes bake setup preparing for bake starting a bake terminating a bake in progress oven cool down bake setup load trays onto racks in the oven close and latch the door preparing for bake 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 starting a bake 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 terminating a bake in progress 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 oven cool down 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 maintenance this maintenance schedule applies to blue m ovens for additional information, refer to the product manual daily or start of operation inspect interior for debris inspect door gasket and ensure that the door closes securely clean gasket as needed monthly 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) quarterly 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 yearly calibrate temperature yuanyao oven product manual manufacturer document that contains safety, installation, operation and maintenance information baking profiles 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 import an oven program 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 i mport 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 operation this operation section describes starting a bake terminating a bake in progress for additional operation information, refer to the docid\ hukhdkofw9hthse0dd8ly above starting a bake 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 terminating a bake in progress 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 maintenance yuanyao oven for additional information, refer to the docid\ hukhdkofw9hthse0dd8ly above daily or start of operation inspect interior for debris inspect door gasket and ensure that the door closes securely clean gasket as needed monthly 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) quarterly 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 yearly calibrate temperature general safety & notes cryogenic liquid safety nitrogen handling cryogens 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 cryogen safe work practices 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 lma notes 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 docid 7ne6rgdaszpapohh5qozm contact information carbon for questions and support related to inert baking parts made with carbon resins, please contact docid\ k86zo5vcyn wqjl3vdgft blue m blue m 2821 old route 15 new columbia, pa 17856 usa +1 570 538 7200 https //www bluem com yuanyao 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 https //www yuanyao tech com thermal product solutions +1 800 586 2473 https //www thermalproductsolutions com