Printed Circuit Board Assembly & PCB Design SMT Electronics Assembly Manufacturing Forum

Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.


inspection system

#24130

inspection system | 14 April, 2003

Hi, I am interested in 2D inspection system.Principle work important parameters,requirements etc.If anyone can help please reply.Any articles,pdf,url or books?Any place I can read about it?

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#24131

inspection system | 14 April, 2003

What 2D inspection? Solder Paste deposition perhaps? Transmission X-ray?

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#24135

inspection system | 14 April, 2003

Pete I'm not very informed about it but from the things I red today - 2D inspection : solder component solder joints x-ray and what ever type exsist.

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Greg

#24143

inspection system | 14 April, 2003

Try looking at http://www.tresmine.com.au website for first off inspection unit. Look in the Cluso Inspection Systems section.

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#24145

inspection system | 15 April, 2003

Don't have any specific links to papers and articles. Try searching on the IPC.org (plus APEX show http://www.goapex.org) and SMTA.org web sites. Any papers and articles on the process from equipment mfg.'s should be taken with a grain of salt.

Solder paste is inspected by 2D systems for paste coverage over the solder land. There are also 3D systems that actually measure the paste volume of a deposit on the solder land.

Components are inspected via. Automatic Optical Test (AOT) for pre-solder inspections for component I.D, absence, presence, orientation, markings, etc... as well as measuring the component placement position in X-Y-Theta and Automatic Optical Inspection(AOI) systems for pre and post solder that perform component inspections, same as AOT but no measuring placement position, as well as inspect solder joints that can be "seen" by the camera(s).

Transmission X-ray, often referred to as "2D", is purported to be the most effective method for true volumetric solder joint measurement. However, there are limitations when inspecting double-side PCB assemblies. Cross-Section X-ray, often referred to as "3D", systems obtain images by "slicing" through an assembly. Where this method overcomes the limitations of Transmission, it is not intended for volumetric solder joint measurement.

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Dr. Chester Lowe

#24296

inspection system | 25 April, 2003

There are many complementary systems ie x-ray, etc that are utilized for these inspections.

What is the ultimate goal and/or future needs for you?

Cheers, Chester www.feinfocus.com

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#24300

inspection system | 25 April, 2003

Go to http://www.gsilumonics.com we use several of their systems for both paste and component inspection and week in and week out maintain a 99.85%+ first pass yield on a no post reflow repair line.

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#24347

inspection system | 29 April, 2003

Pete,

I have to disagree with your statement regarding 3D Xray not being a good source of determining solder volume. The Agilent 5DX is absolutely fantastic at determining volume. However, cost of the system makes it not very practical.

Jason

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#24356

inspection system | 30 April, 2003

Thanks for all posts. In links you gave me I found very interesting things.

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#24361

inspection system | 30 April, 2003

Jason,

In Transmission AXI the entire solder joint volume is imaged, not just a slice (no missing information) as with Cross-Section. Also, there is no signal loss from mechanical or digital image reconstruction (highest contrast and edge strength). Further, Transmission AXI can detect �out-of-slice� defects that cannot be detected by cross-section AXI, such as a bridge located higher up a lead pair. Cross-Section AXI can not inspect solder volume to the accuracy level that Transmission AXI can.

Pete

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#24362

inspection system | 30 April, 2003

Yes, your "slice theory" is correct, but ask yourself "how many slices?" This is the trick. By adding "slice points", you increase the robustness of the image. At the same time, you add time to the scan. Not too much that it outweighs the benefits, though. One more thing....try getting an image of vacuolar porosity underneath the lead termination and pad with transmission Xray....can't be done!

Jason

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#24363

inspection system | 30 April, 2003

Yes, there is a limitation with Transmission X-ray on double-side SMT boards, ie.: back-to-back solder joints, components on bttom side over a solder joint.

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