UNIVERSITY OF ILLINOIS AT URBANA/CHAMPAIGN - COMPOSITES MANUFACTURING LAB

Autoclave Operations Manual

Version 1

Written by KRH

2/21/2011

Contents ACCS .............................................................................................................................................................. 4

Alarms ....................................................................................................................................................... 7

Main Display Tabs ..................................................................................................................................... 7

Process Control Loops ........................................................................................................................... 7

Load Management Screen .................................................................................................................... 8

Recipe Parameters ................................................................................................................................ 9

Sensor Display ..................................................................................................................................... 10

Graphical History ................................................................................................................................. 10

Summary Information ......................................................................................................................... 11

Event History ....................................................................................................................................... 11

Real-time Display ................................................................................................................................ 12

System Control Screen ........................................................................................................................ 12

Load and Run Recipe ........................................................................................................................... 13

Abort Recipe........................................................................................................................................ 13

Hold Recipe / Control Continue .......................................................................................................... 13

Skip to Next Segment .......................................................................................................................... 13

Launch Recipe Manager ...................................................................................................................... 13

ACCS Options .......................................................................................................................................... 13

Recipe Control ..................................................................................................................................... 13

Data Logging ........................................................................................................................................ 13

Alarms ................................................................................................................................................. 13

Soak Recalculation .............................................................................................................................. 13

BetaBrite ............................................................................................................................................. 14

Alarms ......................................................................................................................................................... 14

Automatic Alarms ................................................................................................................................... 14

Control Power ..................................................................................................................................... 14

E-Stop .................................................................................................................................................. 14

ACCS .................................................................................................................................................... 14

Autoclave Temp .................................................................................................................................. 14

Autoclave Pressure ............................................................................................................................. 14

Autoclave Transducer ......................................................................................................................... 14

Fan Motor Temp ................................................................................................................................. 14

Water Level Switch ............................................................................................................................. 15

User Defined Alarms ............................................................................................................................... 15

Touch Screen ............................................................................................................................................... 15

Startup Screen ......................................................................................................................................... 15

Main Display ............................................................................................................................................ 16

Process Display ........................................................................................................................................ 16

Graphical Display .................................................................................................................................... 17

Recipe Manager .......................................................................................................................................... 17

Creating a New Recipe ............................................................................................................................ 17

Max Vessel Temp Setpoint .................................................................................................................. 18

Max Part Soak Temp ........................................................................................................................... 18

Target Temp ........................................................................................................................................ 18

Min Part Soak Temp ............................................................................................................................ 18

Soak Time ............................................................................................................................................ 18

Temp Rate Source ............................................................................................................................... 19

Max Part Temp Rate ........................................................................................................................... 19

Desired Part Temp Rate ...................................................................................................................... 19

Min Part Temp Rate ............................................................................................................................ 19

Max Vessel-to-Part Diff ....................................................................................................................... 19

Max Part Internal Temp Diff ............................................................................................................... 19

Exothermic Limit (Ramp Up) ............................................................................................................... 19

Target Pressure ................................................................................................................................... 19

Vessel Pressurization Rate .................................................................................................................. 19

Rate Mode Control .............................................................................................................................. 20

Start Pressurization Trigger Temp....................................................................................................... 20

Trigger Source ..................................................................................................................................... 20

Pressure Deviation Limit ..................................................................................................................... 20

Target Vacuum .................................................................................................................................... 20

Vacuum Header Rate .......................................................................................................................... 20

Vac Rate mode Control ....................................................................................................................... 20

Vac Header Trigger Temp and Vac Header Trigger Pres ..................................................................... 20

General Miscellaneous Information ........................................................................................................... 20

Default Passwords ................................................................................................................................... 20

Backup of ACCS Software ........................................................................................................................ 21

Running the Autoclave in Manual Mode ................................................................................................ 21

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.

Compressor

On/Off Switch

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.

Nitrogen Tanks mounted in manifold locations in room 13

4. 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.

Valve to main

manifold line

Butterfly Valve

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

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).

Automatic / Manual Mode Indicator Controller Setpoint

Current controller

reading

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

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

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.

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.

TC Readings

TC Rates of

Change

TC / Transducer

Toggle Switch

Min/Max/Ave and

All TC reading

Toggle Switch

Red – Vessel

Temp Reading

Blue – Allowable

Vessel Temperature

Region

Yellow – Part TC

readings

Light Blue – Vacuum

Transducer Reading

Gray – Vessel Pressure

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.

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.

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

Interval Update Frequency

Alarm Indicators

System Indicators

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

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.

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.

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.

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

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.

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.

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.

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.