Vincotech 2xflowSCREW4w, Handling Instructions Manual

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flowSCREW 4w packages
Copyright Vincotech
Handling Instruction
03 rem. sect. 5.2; mod. at sect. 5.1 29.09.2014
Gyimóthy Zs.
Gyetvai T.
FSWB-M-*-HI
Page
15 /
18
02 remove section 6.2 14.05.2014
Gyimóthy Zs.
Gyetvai T.
01 20.02.2014
Gyimóthy Zs.
Gyetvai T.
Ver. Alteration Date Des. / Mod. Appr.
9.2.1 Basic requirements for press-fitting
Ensure press-fit pins are pressed into the holes on the PCB at the correct depth. The center of
the press-fit pinhead has to be at least 0.5 mm below the top surface and at least 0.5 mm
above the bottom surface of the PCB (
Figure 13 ).
Figure 13: Press-in depth in a PCB
9.3 Process control parameters
The following values are relevant to quality and should be taken into consideration if the
pressing machine is able to record force-stroke values during the process.
Figure 14 diagrams
a normal press-fitting procedure. It shows three different sections:

First ascending section (blue): The heads of the press-fit pins slide in and deform to fit
into the holes. This section ends with a local maximum.

Second section (green): The centers of the pinheads are inside the holes. The pins slide
all the way in to reach their final positions. This section ends with a local minimum.

Second ascending section (red): The pins come to a stop. The press-in tool starts to
bend the PCB.
The pressing action has to stop at the beginning of the second ascending section to prevent
damage to the PCB. The press-in force or the tool's stroke motion has to be controlled so it
stops at this point.
Process control parameters can be set as follows:

The local maximum value (end of the blue section) of the force-stroke diagram has to
be:
o
higher than 90 N x number of pins
o
lower than 150 N x number of pins

These limits are indicated in the diagram. If the press-in force is not within this range,
the plating may be faulty or the holes' diameter may be incorrect.