We recently relocated to a new building in So. Ca. Our manufacturing
floor is about 60,000 square feet with a 28 foot open air ceiling. I
was told, by our facilities department, prior to moving to this location
that the manufacturing floor would have a $200,000 temperature and
humidity control system, but when we got here there was none. Needless
to say our temperature and humidity has been all over the place. When
the temperature is high and the humidity is up around 70% the water
soluable solder paste runs all over the place, and what a mess. When
the humidity is too low the solder paste becomes so dry you can not get
it to roll properly on the stencil and naturally it doesn't print very
well. Our yeild went from 99% to 96%.
I have purchased humdidifiers and de-humidifiers to recitfy the problem,
but this is only a bandaide approach. If you have the chance to spec in
humidity and temperature control, then do it!! I have spec'd in 35% to
45% humidity, with the temperature at 68 to 72 degrees F. It will
definitely save you all kinds of headaches if you have some sort of
environmental control.
> ----------
> From: Juanita Zeinstra[SMTP:[log in to unmask]]
> Sent: Friday, January 16, 1998 10:30 AM
> To: [log in to unmask]
> Subject: [TN] Assembly Floor Humidity Requirements
>
> We are located in Grand Rapids Michigan. We are moving across
> town to
> a new building which is being renovated to suit our needs. With
> a
> tight budget getting tighter, there is a somewhat political and
> emotional contest in the making.
>
> By title our assembly facility will be called the "Engineering
> Manufacturing Development Center (EMDC)". Engineering activity
> is
> located in Grand Rapids, Mi. while production manufacturing will
> be
> located in Clearwater, Fla. The EMDC will have process
> development,
> low volume and transition responsibilities.
>
> We assemble primarily SMT boards but there is some thru-hole and
> mixed
> technology as well. Processing in the EMDC includes wave, vapor
> phase, and hand soldering. IR, convection ovens or even new
> technolgy
> soldering may be added later, as well. Our boards are primarily
> rigid
> polyimide boards but flex and rigid-flex boards are processed
> occasionally. Thermount boards are being considered for the
> future.
> Cu-Invar-Cu and Cu-Mo-Cu stabilizing cores are frequently
> employed for
> CTE stabilization.
>
> We will be using more and more plastic and commercial parts and
> less
> of the ceramic and military grade parts, as is the industry
> trend. It
> also goes without saying that expect to track industry trends in
> technology, components and processing.
>
> We are in the business for the long term. We started our
> operations
> in GR in the early 1950's and we will have a 20 year lease on our
> new
> facility. Our business niche is high technology commercial and
> military avionics. Our facility size is almost 900,000 Sq.Ft.
> and the
> EMDC and circuit card assembly areas could be as large as 15K-25K
> Sq.
> Ft. in size.
>
> With that as background, the question is as follows;
>
> What temperature / humidity requirements would you recommend for
> the EMDC and assembly areas of our new facility?
>
> ##############################################################
> TechNet Mail List provided as a free service by IPC using LISTSERV
> 1.8c
> ##############################################################
> To subscribe/unsubscribe, send a message to [log in to unmask] with
> following text in the body:
> To subscribe: SUBSCRIBE TECHNET <your full name>
> To unsubscribe: SIGNOFF TECHNET
> ##############################################################
> Please visit IPC web site (http://www.ipc.org/html/forum.htm) for
> additional information.
> For the technical support contact Dmitriy Sklyar at [log in to unmask] or
> 847-509-9700 ext.311
> ##############################################################
>
##############################################################
TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c
##############################################################
To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body:
To subscribe: SUBSCRIBE TECHNET <your full name>
To unsubscribe: SIGNOFF TECHNET
##############################################################
Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information.
For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311
##############################################################
|
