Westcode Semiconductors CMK Application note
Mounting
It is important to observe the correct mounting procedures when using Power Semiconductors to ensure
effective cooling, good current conduction and
procedure.
(1)
ALUMINIUM
Apply a
25mm rotary wire cup brush
or surfaces,
clamp
approximately
grease
(2)
Ensure that the device contact surface is clean (a scouring pad, such
effectively) then apply a thin film of mounting grease
free of mounting grease.
Assembly procedures are important:
(1)
Using 'bar' clamps, either double side or single side, it
before tightening. The screws should
the nuts should be alternately tightened half a turn until the pressure indicating system shows that the
required pressure has been achieved. .
Using a 'box' clamp, position it over the device ensuring that the pins are correctly located.
square steel plate over the central rod, feed bolts (with shakeproof washer) through the clamp whilst
holding it firmly
touches the heatsink
small amount of mounting
in
position observing the clamping procedures below. Warning: a small amount of grease of
will cause a high voltdrop across the joint and affect heat transfer.
STUD
CAPSULE devices:-
BASE devices:-
HEATSINKSC') for CAPSULE and FLAT BASE devices:-
grease(b)
is
ideally suited); this action produces a 'slurry'. Clean the mounting surface,
in
the case of double cooling. Apply a thin film of mounting grease to the semiconductor, and
0.1
mm diameter should be squeezed out of the device/heatsink joint. Excessive use of
be
in
place. Screw the bolts 'finger tight', then alternately, clockwise, half a turn until the box
all
the
way
round.
to the heatsink. Scrub the heatsink area with a wire brush (a
'finger' tightened initially, then, using a suitable spanner (wrench)
Procedures
reliability. Heatsink preparation
as
'Scotchbrite', will remove dirt
to
the device ensuring that the threads are clean and
is
important to ensure that all faces are parallel
is
a vital part of the
Position the
(2)
FLAT
(SQUARE)
Apply mounting grease
screws, then 'finger' tighten them, followed by a torque controlled spanner (wrench)
torque.
(3)
STUD
Ensure that no mounting grease is
controlled spanner (wrench)
WESTCODE
Pole Face dia. Basic Clamp
19mm CMK
25mm CMK 450x56M
25mm CMK 450B25M
29.5mm (GTO only) CMK 550x56M
34mm CMK 1130x76M
34mm CMK 1500B34M
47mm (GTO only) CMK
47mm CMK 2140x76M
63mm (GTO only) CMK 2500x116M
63mm CMK 3000x116M
75mm (GTO only) CMK 3500x116M
73mm CMK 4000x116M
87mm (GTO only) CMK 5000x128M
87mm CMK 7000x128M
BASE
offer a range of mounting clamps for capsule devices:
BASE
devices:-
devices:-
as
for capsules. Ensure that
on
the screw thread. Tighten only the hexagonal base using a torque
to
the limit stated for the device.
450B19M
21
00x76M
no
mounting grease or lubrication is
Type of Clamp
Box Clamp
Bar/single/double
Box Clamp
Bar/single/double
Bar/single/double
Box Clamp
Bar/single/double
Bar/single/double
Bar/single/double
Bar/single/double
Bar/single/double
Bar/single/double
Bar/single/double
Bar/single/double
on
the fixing
to
1.66 - 2.07 Kgm
NOTES:
(a)
Recommended machining tolerances over the device mounting area - Flatness 0.03mm, Roughness
1.6\-1
metres
(b)
Recommended mounting grease
Ra
-ILEX
sex
13
or PENETROX A-13
36
Loading...