Calibration of SMT (Surface Mount) Assembly Machines

#11
I have a screen printer, SMT assembly (pick and place) machine and a reflow oven. We have never calibrated or verified the screen printer as there are no instructions for doing so in the manual. Our SMT machine can be self-verified in two ways. Every time the machine turns on, it "homes" itself and then goes from home to a verifiable position on the other side of the machine and checks the encoder counts on the X & Y. It also checks Z axis using its built in laser measurement system. The laser measurement system can be verified against a block that came with the machine. Our reflow oven uses top and bottom heaters with PID controllers in each zone. Any out of tolerance condition would rapidly become obvious unless both controllers in one zone failed at the same time. Therefore, we have only verified that the temperature readings are correct using a traceable temperature meter.

We do perform the preventive maintenance as required by the manual for each piece of equipment and this is listed in our ISO preventive maintenance procedure. However, the SMT equipment is not listed in our calibration pool and I don't have a traceable calibration record for these items. Remember that there is a "where necessary to ensure valid results" in Section 7.6. If your SMT process is stable (i.e. you screen solder in the right place, put parts in the right places, and solder the parts properly) without extensive calibration and verification, then you don't need to add unnecessary burden.

7.6 "The organization shall determine the monitoring and measurement to be undertaken and the monitoring and measuring devices needed to provide evidence of conformity of product to determined requirements." Our customers do not require that we screen Q amount of solder at R coordinates, place part X at location Y and reflow solder at temperature Z. They require the finished assembly to meet their requirements. Consider.

My evidence of conformity is the 99.9% first pass yield of my surface mount assemblies at final test.
 
Last edited:
Elsmar Forum Sponsor
J

justncredible

#12
http://www.renishaw.com/en/7968.aspx

Can you get a pick and place SMT machine calibrated,,, I would say YES. Do you have to, I would say NO. Will it increase your placement success, maybe.

I would do a study on misplaced or misaligned parts, benchmark it before and after.

I have sat on SMT production lines and done touch up, I know the machines should be better, and it may allow you to cut touch up time.

Here we calibrate our CNC machines once a year or after a major crash with lasers. These are okuma vert lathes, they measure nothing, once error mapped and calibrated they can hold very tight tols. No one forces us to do this either, it is just good business. We prevent the problems before they occur. Imagine that......
 
#13
However, the SMT assy machinery is not calibrated equipment because, again I am reitterating a previous post, it does not "measure". I fought this battle when I took over that job and FINALLY won.
Be careful and be ready for this battle. My pick and place machine measures parts via laser and will reject them if they are out of tolerance (e.g. an 0603 instead of an 0805). It also measures pin coplanarity, alignment and pitch on QFPs to assure that everything will solder on a fine pitch placement. Your reflow oven is also measuring process parameters. If your temperature measurements are not correct, you may not be soldering properly. I am not suggesting that you should calibrate your SMT machines, but you do need to know exactly why you are not calibrating them.
 
V

vanan10

#14
I agree with the posts that calibration of SMT machines should be carried out when there is a drop in machine performance. But unfortunately in my case the monitoring is conducted live, through in-line SPI's and AOI's. Hence the pressure to do calibration at regular intervals to maintain high yield at the inspection machines. Add to this high-density (80 -90% populated) PCBA's with a minimum separation of 6mils, and line utilization not less than 85%.

But like what many pointed out, it all boils down to what customer wants. I guess my problem stems from a demanding 'internal' customer:)

Is there a thread on how to maintain high yield for pure SMT lines or some similar threads?
 
Thread starter Similar threads Forum Replies Date
lanley liao Question regarding the calibration of monitoring and measure equipment. Oil and Gas Industry Standards and Regulations 0
N IATF Calibration Lean in Manufacturing and Service Industries 3
Q Do these certificates of calibration meet ISO 9001 requirements for traceability to NIST? ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 10
T Plug Gage Calibration Calibration and Metrology Software and Hardware 1
M Load Cell Calibration using a totalizer on a flow meter General Measurement Device and Calibration Topics 0
E Calibration Records needed ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 1
D Limited Range Calibration - 5000 lb Industrial floor scale General Measurement Device and Calibration Topics 3
D Calibration of Small Scales General Measurement Device and Calibration Topics 26
C How to Establish the Calibration & Measurement Capability (CMC)? ISO 17025 related Discussions 1
I IQOQ or just initial calibration required? General Measurement Device and Calibration Topics 3
B Calibration in real life ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 3
J Calibration cycle for monitoring & measuring tools used in medical device manufacturing General Measurement Device and Calibration Topics 5
A Is calibration of test weight required General Measurement Device and Calibration Topics 4
S Calibration Frequency for Slip Gauge Kit used for CMM Calibration? General Measurement Device and Calibration Topics 0
S Calibration/Verification of customer fixtures IATF 16949 - Automotive Quality Systems Standard 6
Ron Rompen Calibration by manufacturer ISO 17025 related Discussions 4
Q Calibration verification records 7.1.5.2.1 IATF 16949 - Automotive Quality Systems Standard 2
B AS9100D 7.1.5.2 Calibration or Verification Method using outside cal lab AS9100, IAQG, NADCAP and Aerospace related Standards and Requirements 1
W Next Calibration Due Date Calibration Frequency (Interval) 5
S Where do l get calibration standards to run a calibration lab? Other ISO and International Standards and European Regulations 2
A OEM On-Site Calibration issues during Covid19 ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 12
D Calibration tolerance question using Pipettes Medical Device and FDA Regulations and Standards News 1
M Calibration Certificate Result issued by an accredited external laboratory General Measurement Device and Calibration Topics 9
G Calibration of "Master Parts" Used as Gauges Calibration Frequency (Interval) 5
R Calibration lab environmental monitoring General Measurement Device and Calibration Topics 4
G Calibration of Rotronic probe but not digital readout? General Measurement Device and Calibration Topics 3
F Standard Calibration Procedures: Recommended Practice ISO 17025 related Discussions 0
T Temperature Requirements For In House Calibration - AS9100 AS9100, IAQG, NADCAP and Aerospace related Standards and Requirements 16
B Gage calibration frequency, ISO and IATF - What are the requirements Calibration Frequency (Interval) 3
Crimpshrine13 Laboratory Scope - Calibration vs. Test Methods - IATF 16949 IATF 16949 - Automotive Quality Systems Standard 3
Crimpshrine13 Calibration of pH Meter Probe Calibration and Metrology Software and Hardware 3
F ESD workbench "calibration" Manufacturing and Related Processes 2
C Correct Calibration Method for Dial Depth Gage General Measurement Device and Calibration Topics 6
F Nist traceable calibration certificates General Measurement Device and Calibration Topics 1
G Tool tracebility and First calibration requirements for aerospace (AS9100) organisation AS9100, IAQG, NADCAP and Aerospace related Standards and Requirements 5
D Calibration of Digital thermometer with surface probe General Measurement Device and Calibration Topics 1
T Calibration or Verification -> Cm and Cmk, etc. Definitions, Acronyms, Abbreviations and Interpretations Listed Alphabetically 3
G Is repeatability required for equipment calibration? General Measurement Device and Calibration Topics 10
was named killer AS 9100D - Calibration Instructions - Controlled documents? AS9100, IAQG, NADCAP and Aerospace related Standards and Requirements 6
B Photovoltaic Tester Calibration General Measurement Device and Calibration Topics 0
B Temperature loop: partial calibration General Measurement Device and Calibration Topics 10
G Glass scale calibration at 74 degrees F? General Measurement Device and Calibration Topics 4
A Digital Timer Calibration Requirements General Measurement Device and Calibration Topics 3
Ron Rompen Barcode Verifier Calibration and Use Calibration and Metrology Software and Hardware 5
S Is Optical Parallel Set required calibration? ISO 17025 related Discussions 1
A Calibration of Power Supplies AS9100, IAQG, NADCAP and Aerospace related Standards and Requirements 2
D Calibration Process Flow Map Example Wanted General Measurement Device and Calibration Topics 3
M Calibration or Verification? What terminology to use ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 1
N Calibration Requirements for Production Equipment ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 3
S Calibration Equipment Selection General Measurement Device and Calibration Topics 2

Similar threads

Top Bottom