00198574-01_Process_Foundation_DEK_Micron_EN.pdf - 第40页

6 Process Maintenance 6.2 Maintain the Process in Real Time 40 Process Foundation DEK Micron-Series 12/2017 6.2 Maintain the Process in Real Time There may be circumstances during production when small changes to the pro…

6 Process Maintenance

6.1 Copy and Delete Product Files

Process Foundation DEK Micron-Series 12/2017 39

6 Process Maintenance

6.1 Copy and Delete Product Files

Copy and Delete Product Files

There are several reasons why good housekeeping is important with regards to product

files:

●

If the hard disk crashes or there is a software corruption it is relatively easy to replace or

reformat the hard drive and load the windows and DEK software. If all the product files have

been backed up then the machine will be ready to go back into production very quickly

●

If product files are copied onto an appropriate media they can then be transferred to other

DEK printers

●

If there are too many product files on the printer it makes it difficult to find the one you want

and can increase the chance that the wrong one is selected

Depending on the machine type, the options that may be available for COPYING files include

floppy disc, USB memory stick and local area network. In addition, it is possible to PRINT a product

file directly onto paper by connecting a printer to the serial or USB port or alternatively PRINT to file

then transfer to a PC connected to a printer.

Exercise

1. Copy a product file from the printer to a USB memory stick

2. Delete the same file from the printer

3. Copy the same file from the memory stick back onto the printer

4. Print a hard copy of the same file onto paper

Note: Printing creates an ASCII copy of the product file that can then be printed and stored on

record or kept close to the printer as a reference for the operators and technicians to

know what the process parameters should be.

Notes:

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6 Process Maintenance

6.2 Maintain the Process in Real Time

40 Process Foundation DEK Micron-Series 12/2017

6.2 Maintain the Process in Real Time

There may be circumstances during production when small changes to the process are required in

order to compensate for variations in the hardware or environment. Examples include:

●

Variations between batches of boards

●

Temperature fluctuations

●

Multiple stencils with varying accuracy used on same process

●

Wear and tear of process hardware

The underlying reasons for problems like these should be addressed and rectified quickly so that

they do not compromise the aim of high yield and throughput. However, in the short term there are

actions that can be taken to keep production running with minimum defects.

Actions that can be taken in "real time" i.e. without having to stop the printer include:

Recovery Actions Process Adjustments*

●

Under Screen Clean

●

Print Speed

●

Add Paste

●

Print Pressure

●

Knead Paste

●

Separation Speed

●

Alignment Offset

●

Fiducial Set-up

*Adjustment to the process should be restricted to qualified and authorised personnel as making

changes can seriously compromise the production quality.

Note: Changes made whilst running will be lost when the product file is changed or power is

removed from the printer. To make changes permanent stop the machine and save the

file in the menu.

Recording Process Adjustment

It is good practice to record any changes made to the process so that the root cause of the adjust-

ment can be investigated.

Exercise

Cycle a board from left to left with no squeegees and print pressure at 0kg:

1. Adjust the print speed and observe when the change takes effect

2. Instigate a screen clean operation and observe when it takes effect

6 Process Maintenance

6.3 Maintain the Print Enviroment

Process Foundation DEK Micron-Series 12/2017 41

6.3 Maintain the Print Enviroment

Correct Temperature Within Printer

The temperature inside the printer should be stable at the material manufacturer’s recommended

working temperature (normally around 22°C – 24°C for solder paste). Printer covers should be left

closed whenever possible to avoid fluctuations.

Correct Humidity Within Printer

The humidity inside the printer should be stable at the material manufactures recommended

working level (normally around 40% – 65% relative humidity). Printer covers should be left closed

whenever possible to avoid fluctuations.

General Factory Environment

Generally speaking, if the environment is comfortable for humans it will be suitable for the print

material. If you feel uncomfortable (too hot, too cold, too dry) then it is likely that the print

performance of the material will be compromised The factory should have a clean, stable

atmosphere. Ideally it should be air-conditioned with temperature and humidity stable throughout

the day and throughout the year.

Best Working Practices

●

Keep printer covers closed whenever possible to avoid environmental fluctuations

●

Monitor internal temperatures regularly throughout the day

●

Use covers over conveyors to prevent airborne contamination

●

Locate the printer in a clean area away from open windows, direct sunlight, heat sources,

draughts, sources of vibration, etc.

●

Isolate an area around the printer to prevent human traffic, trolleys, etc. coming near the

printer

●

Regularly check that the TCM is switched on, set correctly and all cables are connected

Exercise (if a TMC is present)

Using the TCM operator handbook as a guide, adjust the TCM to the mid-point of the

recommended temperature range for the material you are using.