Autoclave Operations Manual

Transcription

1 UNIVERSITY OF ILLINOIS AT URBANA/CHAMPAIGN - COMPOSITES MANUFACTURING LAB Autoclave Operations Manual Version 1 Written by KRH 2/21/2011

2 Contents ACCS... 4 Alarms... 7 Main Display Tabs... 7 Process Control Loops... 7 Load Management Screen... 8 Recipe Parameters... 9 Sensor Display Graphical History Summary Information Event History Real-time Display System Control Screen Load and Run Recipe Abort Recipe Hold Recipe / Control Continue Skip to Next Segment Launch Recipe Manager ACCS Options Recipe Control Data Logging Alarms Soak Recalculation BetaBrite Alarms Automatic Alarms Control Power E-Stop ACCS Autoclave Temp Autoclave Pressure Autoclave Transducer... 14

3 Fan Motor Temp Water Level Switch User Defined Alarms Touch Screen Startup Screen Main Display Process Display Graphical Display Recipe Manager Creating a New Recipe Max Vessel Temp Setpoint Max Part Soak Temp Target Temp Min Part Soak Temp Soak Time Temp Rate Source Max Part Temp Rate Desired Part Temp Rate Min Part Temp Rate Max Vessel-to-Part Diff Max Part Internal Temp Diff Exothermic Limit (Ramp Up) Target Pressure Vessel Pressurization Rate Rate Mode Control Start Pressurization Trigger Temp Trigger Source Pressure Deviation Limit Target Vacuum Vacuum Header Rate Vac Rate mode Control Vac Header Trigger Temp and Vac Header Trigger Pres... 20

4 General Miscellaneous Information Default Passwords Backup of ACCS Software Running the Autoclave in Manual Mode... 21

5 Turning on the Autoclave and Loading a Part 1. First, ensure that the power transformer is in the ON position. Power Transformer 2. Turn on the Compressor and open the air valve that operates the pneumatic controls. The compressor should reach ~150psi before shutting off. It will re-pressurize the air lines if the pressure drops below 100psi, so don t be alarmed if it turns back on again. On/Off Switch Compressor

6 3. Turn on Nitrogen for autoclave pressurization. Nitrogen tanks are in a bank of tanks outside of the room that contains the old hot press. Make sure to open both valves near the nitrogen tanks, one that is directly on the nitrogen tank and one that is leading to the main line. Also, the main line must be opened. When the main line is opened the pressure gage should read ~2000psi. For one run of the autoclave, you should use ~3 full tanks of nitrogen. When opening the pressurization valve in the autoclave room, open it all the way, less one full turn. Valve to main manifold line Nitrogen Tanks mounted in manifold locations in room Turn on the water by turning the water valve to 1/4. Be careful of water overflow. After turning on the water be sure that the bottom water tank valve is in the open position so the top siphon can work properly. When turning on the water initially, let the water build up in the tank until it reaches the top evacuation pipe. This will cause the siphon to engage and create an equilibrium that will be reached once the water level drops back down to the bottom of the tank after the siphon has engaged. Butterfly Valve

7 5. Load in your part using the cart and attach the thermocouples and vacuum lines (if applicable). To insert a part, open the 2 red double doors in the room containing the autoclave and pull out the cart to extend the autoclave table outside of the autoclave, as pictured below. Place your part on the table and insert any of the vacuum lines as required. Be sure to lock the wheels of the cart before sliding out the autoclave table! Cart attached to autoclave 6. Place the part inside and remove the cart. Close the autoclave door by activating the pneumatic actuator on the side of the door and pulling the door close handle towards you. This will rotate the sealing ring counter clockwise and seal the autoclave. After activating the pneumatics, engage the manual lock and the pneumatics should turn off. Your part is now loaded and you may begin processing. Autoclave door actuator with pneumatic controls Door open/close knob

8 ACCS The Autoclave Computer Controlled Software (ACCS) is the main interface for nearly all of the autoclave operations. The following gives a detailed outline of the ACCS software. Alarms ACCS will alarm when certain parameters are violated (See alarms section, pg. 15). When an alarm is triggered, the operator will be alerted both visually, on the computer screen, and audibly via the system s alarm. To acknowledge an alarm, press the ESC key once. To dismiss it entirely, press the ESC key a second time. You should see the alarm disappear from the computer screen. This alarm will not activate again during the current segment if the operator acknowledges and dismisses the alarm. Picture of alarm activated Main Display Tabs Process Control Loops This button brings up the current pressure, temperature and vacuum settings along with their active set points. A red display indicates that the parameter is operating in manual mode, either through ACCS or through the touchscreen. To relinquish control to ACCS press the M (manual) in the lower right corner of the parameters indication screen to change it to A (auto). Current controller reading Automatic / Manual Mode Indicator Controller Setpoint

9 Load Management Screen This button brings up the load management screen. This screen is where all of the parts being run in the current recipe are defined. Thermocouples and transducers are also defined here. System must be offline to enable editing. To bring online press either the Online Load or the Commit Load button. Defined Parts Thermocouples and transducers defined for each part

10 Recipe Parameters The recipe parameters button shows the current recipe, which segment of the recipe is currently running and allows you to override any of the current recipe parameters, if desired. To override, simply type the value you wish to alter in the corresponding Override box. To relinquish control to the recipe type auto into the override box. Override Boxes

11 Sensor Display Thermocouples and transducers that were defined in the load management screen are displayed in this area. Thermocouples and transducers can be deactivated in this tab, if desired. Deactivated thermocouples will not trip alarms, such as the max part temp diff alarm. Min/Max/Ave and All TC reading Toggle Switch TC / Transducer Toggle Switch TC Readings TC Rates of Change Graphical History This tab displays the graphical history of the autoclave run. Data lags behind real time by 5 minutes. Therefore, data will not be displayed in this graph until there is atleast 5 minutes of run-time. Yellow Part TC readings Red Vessel Temp Reading Blue Allowable Vessel Temperature Region Light Blue Vacuum Transducer Reading Gray Vessel Pressure

12 Summary Information This tab shows information about the current parameter setpoints and rates of change as well as total elapsed time, total soak time for the current segment and other useful information. Event History This tab displays all errors, messages and other warnings from the system.

13 Real-time Display This tab gives a running display of the current temperature, pressure and vacuum. Sampling rates and axes can be altered on this chart by going to the customize tab. Interval Update Frequency System Control Screen This tab brings up all of the indicator lights for the autoclave. This is similar to the old HUD that contained all of the indicator lights. Manual operations can be performed from this tab. Time stamp HH:MM:SS System Indicators Alarm Indicators

14 Load and Run Recipe When pressed, this button will prompt you to load and run a pre-defined recipe. Abort Recipe This tab will stop the current cycle Hold Recipe / Control Continue This button will pause the current segment. Soak times and ramps will be held at their current value until the control continue button is pressed. Skip to Next Segment This button skips to the next segment. You will be asked if you are sure you wish to continue before you proceed. Once you ve moved on to the next segment there is no going back, unless you reload the recipe. Launch Recipe Manager This button launches the recipe manager program (See recipe manager, pg. 17) ACCS Options Recipe Control Recipe Algorithm Do not alter these settings, as they have been precisely calibrated by the autoclave technician. Soak Criteria These indicators will dictate when the soak time is activated. If neither is checked, the soak time will begin as soon as the autoclave temperature reaches the Min Part Soak Temp defined in the recipe. Computer-Controlled Valves Checking or unchecking this box has no effect in our control system. Data Logging This tab allows the operator to change how often data is recorded by the ACCS control system for printout in the report manager. Default is 60 seconds. Alarms This tab displays the erratic TC alarm. If a thermocouple strays from this value in a certain amount of time, an alarm will sound. Soak Recalculation As a default, once all of the thermocouples are in the zone between min part soak temp and max part soak temp, the system will start the timer for soak time and will continue regardless of if one of the thermocouples then strays from the temperature control region. However, this can be altered in this

15 option menu so that the soak time is extended if one of the thermocouples strays from the min or max part soak temp. This does not apply in vessel control mode. BetaBrite This is not available with our system, and this tab is useless. Alarms A variety of alarms exist which fall into two main categories. The first main category is the automatic alarm functions. Automatic alarm functions are always active, regardless of which recipe is currently being run. Automatic alarms must be acknowledged in ACCS and also on the touch screen. Most automatic alarms will not stop the current cycle, but some may. The second main category of alarms is the user defined alarms. These alarms are activated when the autoclave is not meeting the parameters defined by the operator s recipe. In example, these types of alarms may go off if the operator defines a vessel pressurization rate of 10 psi/min and the autoclave can only pressurize at a rate of 5 psi/min. User defined alarms must be acknowledged in ACCS, but are not always shown by the touch screen. Automatic Alarms Control Power This alarm will activate if the control power is de-activated while the autoclave is running E-Stop This alarm will activate if the emergency stop button on the console is pressed ACCS This alarm will activate if the ACCS software is not communicating with the hardware. This is monitored by the watchdog which sends a ping between the hardware and software approximately every 3 seconds. Autoclave Temp This alarm will sound if the temperature exceeds 700F. The autoclave is rated to withstand temperatures up to 1000F, but this alarm is triggered to give ample warning. Autoclave Pressure This alarm will sound if the pressure in the autoclave exceeds 310 psi. Autoclave Transducer This alarm will sound if the pressure transducer sends an electrical signal out of its 4 to 20 ma range. Fan Motor Temp This alarm will sound if the fan temperature exceeds 150F. It will also sound if the cooling water is not active when the autoclave fan is running.

16 Water Level Switch This alarm will sound if the water level in the overflow tank gets too high. If this alarm sounds, it s probably a good idea to reduce the cooling to the autoclave or completely close the butterfly valve which controls the water coolant flow. User Defined Alarms User defined alarms are triggered by many different events which can occur doing a curing cycle too many to name in this space. These alarms will be shown in ACCS and will require the user to acknowledge them. Read the alarm and take the appropriate action. Most of these alarms will come from parameters specified in the recipe. Touch Screen The touch screen provides a more direct control to the autoclave. Many manual functions can be input here and much of the autoclave hardware is powered up and controlled here. Startup Screen The startup screen is displayed when the control power is turned on.

17 Main Display The main display provides a small level of control for the temperature, pressure and vacuum in the autoclave. Heating control, the autoclave fan, cooling control, pressure control and the vacuum pump can all be turned on and off from this screen. Note, if the door is unlocked, the heating control, pressure control and cooling control cannot be turned on. If one of the systems is highlighted in yellow and has red letters (see temperature control in figure below), then that particular control system is being run in manual mode (See Process Display Screen). Part thermocouple temperatures are also displayed on this screen. Process Display The process display shows the current readings and setpoints of any particular control system. It also displays how aggressively the control system is attempting to change its current value. For ex ample, a reading of 50 in the pressure setpoint aggression means that the pressure is exactly where it should be. A reading of 100 indicates the pressure control system is trying to add pressure as fast as it possibly can. A reading of 0 means that the pressure is being vented as fast as it possibly can.

18 Graphical Display The graphical display shows the current state of the autoclave in graphical mode. The part sensor screen can be reached from this screen. The part sensor screen Shows the current readings of the thermocouples in the system and the pressure on the vacuum transducer. Recipe Manager The recipe manager is where the curing cycle is programmed. A recipe must be defined if the autoclave is to be run in automatic mode. The recipe manager can be opened using the Launch Recipe Manager button in ACCS or by double clicking the icon on the desktop of the main computer. When opened, the recipe manager will prompt you to select a current recipe or you can create a new recipe. Creating a New Recipe Important to note when creating a new recipe, is how the part(s) being cured will be monitored. Temperature feedback to ACCS can be provided with J-Type thermocouples attached to the part, or with the vessel temperature itself. The following section will assume vessel feedback. Special notes have

19 been added in red for recipes which use thermocouples on the part(s) for part control and feedback. Please use J-Type thermocouples in the autoclave. Recipes are broken down into individual segments. Each segment contains a ramp and a hold section. Each one of these segments is broken down into various parameters which are defined in the process parameters chart. The following provides a brief description of each process parameter. Max Vessel Temp Setpoint This parameter defines the maximum temperature that the autoclave will be allowed to reach during that particular segment. Note, this temperature must exceed that of the max part soak temp. When controlling in vessel mode, this temperature will not be reached. Note, if controlling with part thermocouples, the autoclave will continue ramping up in temperature at the defined desired part temp rate until the first part TC exceeds the min part soak temp. This can frequently happen if there is considerable thermal lag between the temperature of the autoclave and the temperature of the part(s). The autoclave will not exceed the max vessel temp setpoint during this time. Max Part Soak Temp This parameter defines the maximum part soak temperature. Once the vessel enters the region between minimum and maximum soak temperature, the timer for the soak time will be activated. Note, if controlling with part thermocouples, the autoclave will hover around the max part soak temp until all thermocouples reach the min part soak temp while heating. The opposite will happen if cooling. Once all part thermocouples are in the soak temp region, the soak time clock will begin. Target Temp This is the target plateau temperature for the current segment. The control system will attempt to hover at this value during the current segment. Min Part Soak Temp This parameter defines the minimum part soak temperature. Once the vessel enters the region between minimum and maximum soak temperature, the timer for the soak time will be activated. Note, if controlling with part thermocouples, the autoclave will hover around the max part soak temp until all thermocouples reach the min part soak temp while heating. The opposite will happen if cooling. Once all part thermocouples are in the soak temp region, the soak time clock will begin. Soak Time This is the amount of time that a part will be exposed to the target temp. The timer for the soak time begins as soon as the vessel temperature goes above the min part soak temp. If using thermocouples, the soak time begins when all thermocouples are between the min part soak temp and max part soak temp. If a zero value is entered in this box then the control system will proceed to the next segment as soon as the first thermocouple breaches the min part soak temp.

20 Temp Rate Source This tab defines weather you will use vessel temperature or part thermocouple temperature as the control for the system. Right click this box to select different control types. Max Part Temp Rate This is the maximum rate at which the part is allowed to heat or cool. If operating in vessel mode, then the alarm will sound if the vessel heats or cools faster than this value. If operating with thermocouples, the alarm will sound if any of the thermocouples heat or cool faster than this specified rate. Desired Part Temp Rate The autoclave will attempt to control the temperature ramp rate of the vessel to this value. If thermocouples are used, the autoclave will attempt to ramp the average rate of all the thermocouples at this specified value. Min Part Temp Rate This is the minimum rate at which the part is allowed to heat or cool. It is wise to set this value to a low number to allow the system to level off at the target temp once it approaches that value. If operating in vessel mode, then the alarm will sound if the vessel heats or cools slower than this value. If operating with thermocouples, the alarm will sound if any of the thermocouples heat or cool slower than this specified rate. Max Vessel-to-Part Diff Thermocouples must be present for this parameter to function properly. This parameter specifies the maximum temperature difference that is allowed between the average reading of the part thermocouples and the temperature inside the vessel. An alarm will sound if this temperature is breached, or if no thermocouples are initially specified in the system. Max Part Internal Temp Diff Thermocouples must be present for this parameter to function properly. This parameter specifies the maximum temperature difference that is allowed between any two thermocouples. An alarm will sound if this temperature is breached or if no thermocouples are initially specified in the system. Exothermic Limit (Ramp Up) Input for this parameter is a temperature value. This parameter will alarm the operator if the part temperature is exceeding the vessel temperature by the specified value during heating. This parameter is only in effect during heating cycles. It can be turned off by typing off as a value. Target Pressure This is the target pressure for the current segment. Vessel Pressurization Rate This is the rate at which the pressure will build in the autoclave. Be aware that there is an upper limit to this value, depending on what the current autoclave pressure is.

21 Rate Mode Control This parameter specifies units for vessel pressurization rate. This can be switched to allow decay to allow for a reduction of pressure as the temperature goes down. Start Pressurization Trigger Temp This parameter defines the trigger temperature for when the pressurization cycle will begin. To activate it instantly, set this value low. Trigger Source This defines what the temperature trigger source for the start pressurization trigger temperature is. Thermocouples or vessel temperature can be specified. Pressure Deviation Limit This parameter specifies the maximum allowable pressure deviation. This is harder to maintain at higher pressures. Target Vacuum This is the target vacuum for the current segment. An alarm will sound if no transducers are specified. Vacuum Header Rate This is the rate at which the vacuum will attempt to follow. Vac Rate mode Control This parameter specifies the units for the Vacuum Header Rate. Vac Header Trigger Temp and Vac Header Trigger Pres These two parameters trigger the vacuum in the current segment. They work by OR logic, ie. if one of the parameters is met, the controls will attempt to reach the target vacuum. General Miscellaneous Information Default Passwords To run the autoclave, most of the time you will log in as an operator To log in as an operator use password: uoi Further privileges are granted if an administrator password is used. When running the autoclave, use the operator login. If specific changes to tuning or other control parameters must be altered the following can be used, Login Name: admin Password: admin The maintenance tab on the touch screen also has some other options which can be accessed.

22 To log into the maintenance tab on the touch screen use the following: Login Name: op Password: op Backup of ACCS Software A backup of the ACCS software is on the hard drive of the current lab manager. At the time of this publication, the lab manager is Kevin Hart (hart22@illinois.edu). Running the Autoclave in Manual Mode The autoclave can be run in manual mode by entering set points in the Process Control on the touch screen. Note that reports, time history, etc. cannot be generated when run in this mode. Programming a recipe is strongly advised.