CHAPTER 6: ADVANCED WELD FUNCTIONS
MODEL HF2 2 kHz HIGH FREQUENCY RESISTANCE WELDING POWER SUPPLY
990-057
6-7
UP/DOWNSLOPE (Figure 6-13)
Up/Downslope facilitates welding material
combinations such as aluminum-to-aluminum or
platinum-to-tungsten. Up Slope allows a reduction
in electrode force, resulting in a cleaner appearance
by reducing electrode indentation, material pickup
and electrode deformation. Up Slope can also be
used to displace plating and/or oxides, reduce
flashing and spitting, or reduce thermal shock when
welding parts containing glass-to-metal seals.
Downslope assists in the grain refinement of certain
heat-treatable steels and prevents cracking in
aluminum and other materials by reducing the
cooling rate.
Figure 13. Pre/Postheat
Alphanumeric Screen
Up/Downslope can be used with Unitek Peco Force Fired Manual or Air Actuated Weld Heads. For
Manually Actuated Weld Heads, weld current begins when the Force Firing Switch closes. For Force
Fired Air Actuated Weld Heads, weld current begins when both levels of a two-level Foot Switch are
closed and the Force Firing Switch in the Air Actuated Weld Head closes.
When Up/Downslope is used with a Non-Force Fired Air Actuated Weld Head, the Squeeze (SQZ)
Period must be used to allow sufficient time for the electrodes to close and apply the required weld force
to the parts before the Weld Period begins. Weld current begins when the Squeeze Period ends and both
levels of a two-level Foot Switch are closed.
When Up/Downslope is used with any type of Air Actuated Weld Head, the Hold Period can be used to
automatically keep the electrodes closed on the parts after weld current has terminated for the purpose of
providing additional heat sinking or parts cooling. Squeeze and Hold Periods have no meaning with
Manually Actuated Weld Heads and do not appear on either the weld schedule Program or Run screens.
Up/Downslope - Weld Graph Run Screen
(Figure 6-14)
Weld schedule 005 is pre-programmed at the
factory for Up/Downslope operation. The HF2
Weld Control automatically recognizes the
presence of a Manually or Air Actuated Weld
Head before the first weld is made.
Figure 14. Up/Downslope
Weld Graph Screen
