我们也发生过同样的问题.请问一下你们是否用还原锡,还原的锡带杂质是擦拭不掉的.
Best
Regards!
Wisdom
From: TGAsia [mailto:[log in to unmask]]
On Behalf Of Tan Geok
Ang
Sent: Wednesday, January
21, 2009 9:09 AM
To:
[log in to unmask]
Subject: Re:
[TGAsia] dross short
Perform an overhaul in
you wave soldering machine as there is lots of dross within your
solder-pot/pump. You wave height (pump height setting) might also pump dross
within the solder-pot.
From: TGAsia [mailto:[log in to unmask]]
On Behalf Of Yang
Zejun
Sent: Wednesday, 21
January 2009 9:02 AM
To:
[log in to unmask]
Subject:
[TGAsia] dross short
不好意思,我可能没有描述清楚,不良图片和具体的制程参数如下,目前这种不良在我们这里高达5%左右,真的很头疼阿,希望专家们能帮帮忙,谢谢了。
制程参数:
PCB: CEM-1
预热:92摄氏度(实测)
锡条:云南锡业SnPb6337
锡炉温度:254摄氏度(实测)
助焊剂:Interflux 精英IF2008
链条速度:1.2左右
锡炉里的锡渣我们2小时清理一次,锡的量严格控制在波峰未打开时离炉岗10mm以内。
图片中的短路部分不易发现,导致连锡部分在显微镜下观察表面有一层薄薄的像灰一样的东西包裹,但是里面的东西必须用电烙铁才可以带开,这种不良有时候在FR4的PCBA上也会发生
只要是PAD稍密集的地方就容易出现,很苦恼啊....
Zejun Yang |
ME| APC-MGE Critical Power and Cooling Services Division, Schneider
Electric.
(Tel) +86 592 757 2775
| (
James Liu
<[log in to unmask]>
20/01/2009
23:04 |
|
我不明白你的问题。可否有照片?锡丝怎么会短路?
Best
Regards,
James Liu
刘春光
Director, Technology & Standardization
技术与标准总监
IPC
上海市长宁区延安西路1088号2303室
Suite
2303,#1088 West Yan'an
Rd., Changning,
Tel: +86 21 5497
3435
Fax: +86 21 5497
3437
MP: +86 136 0133
3491
[log in to unmask]<mailto:[log in to unmask]>
www.ipc.org.cn<http://www.ipc.org.cn>
________________________________
发件人: TGAsia [[log in to unmask]] 代表
Yang Zejun [[log in to unmask]]
发送时间: 2009年1月20日
11:37
收件人: [log in to unmask]
主题: Re: [TGAsia]
答复: [TGAsia] 关于检验光的要求 !
大家好,我想请问一下锡丝短路怎么处理啊?很细很细的那种。
Zejun Yang | ME| APC-MGE Critical
Power and Cooling Services Division, Schneider
Electric.
(Tel) +86 592 757 2775 |
(
Sent by:
TGAsia <[log in to unmask]>
20/01/2009
11:28
Please respond
to
To
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cc
Subject
[TGAsia] 答复: [TGAsia] 关于检验光的要求!
IPC-610D
和IPC-620A中前言部分有要求:
1.16 Visual Inspection
1.16.1 Lighting
Illumination at the surface of workstations should be 1000 lm/m2 minimum. 1,000
lm/m 2 at the work surface is the accepted practice for the minimum level of
illumination in which operators and inspectors should be expected to perform
their tasks. 1,000 lm/m 2 is approximately equivalent to 100 foot-candles
measured using a photographic light meter.
1.16.2 Magnification Aids and Lighting When required, magnification
power for assembly inspection shall1 be at least the minimum inspection power
specified in Table 1-2. Other magnification powers within the inspection range
may be used. The magnification power requirement is based on the gauge of the
wire being inspected. For assemblies with mixed wire sizes, the greater
magnification may be used for the entire assembly. If the presence of a defect
cannot be determined at the inspection power, the item is acceptable. The
referee magnification power is intended for use only after a defect has been
determined but is not completely identifiable at the inspection
power.
The tolerance for magnification aids
is ± 15% of the selected magnification power. Magnification aids should be
maintained and calibrated as appropriate (see IPC-OI-645). Supplemental lighting
may be necessary to assist in visual assessment.
Table 1-2 Magnification Aids1
Wire
Size AWG
Diameter mm
[inch]
Magnification
Power
Inspection
Range
Maximum
Referee
larger than 14
AWG
2 mm [0.081
in]
N/A
1.75X
14 to 22
AWG
1.6 - 0.63 mm [0.064 to 0.025
in]
1.5X - 3X
4X
smaller than 22
AWG
<0.63mm
[<0.025]
3 –
7.5X
10X
Note 1: Referee
magnification power is to be used only to verify a product rejected at the
inspection magnification. For assemblies with mixed wire size, the greater
magnification may be (but is not required to be) used for the entire
assembly.
Best
Regards,
Sanbor Xiamen Manufacturing,
Inc.
3/4F,
Post: 361026
Tel :+86-592-5099000 ext
8305
Fax:+86-592-5099343
www.sanbor.com
________________________________
发件人: TGAsia [mailto:[log in to unmask]] 代表
发送时间: 2009年1月20日 11:08
收件人:
[log in to unmask]
主题: [TGAsia] 关于检验光的要求!
[cid:_2_05639D0405639AB00013ED0A48257544]
Dear all.
大家好,我想问一下IPC有没有对检验工位的灯光和环境有明确规定的?
∽∽∽∽∽∽∽∽∽∽∽∽∽∽∽∽∽∽
Best Regards
^⊥^
anny
zhou
Welco(Suzhou)
* Phone: 86-512-62838860 ext.
8116
* Fax:
86-512-62830728
* E-Mail:
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