Parker WCS-SIF-01 Training & Maintenance Manual Download Page 5

Page: 5 / 20

WCS-SIF-01

Training & Maintenance Manual

Pneumatic

Parker Hannifin Corporation

Pneumatic Division

Richland, Michigan

www.parker.com/pneumatics

Setup

Below are the step by step setup procedures for properly
setting the flow control and feedback sensor.

How to Set the Flow Control Properly

Begin by turning the flow control clockwise until it stops. If
this is done properly, then the weld stroke should move
extremely slow or not at all.

Note:

As stated in the Installation procedure, the pre-stroke

valve must be actuated prior to the weld stroke valve in order
for the weld cylinder to move correctly.
Slowly (1/4 to 1/ turn at a time) begin to open the flow
control by turning counterclockwise.  The weld tips should
now close upon actuation of the valves. At this point, you
should begin to hear a second exhaust coming from the
weld unit once the weld tips have made contact.  This
second exhaust is the air from the front side of the cylinder
bypassing the flow control. As you continue to speed up the
weld stroke by turning the flow control, the delay between
the tips closing and the second exhaust will get shorter.
Also, check the feedback sensor while this is occurring.  The
indicator light from the sensor should illuminate when you
hear the second exhaust.  This is the key to determining the
proper setting of the flow control.  The optimum setting for
each weld block will be different for each gun, based on the
bore size and weld stroke used. Continue to open the flow
control, allowing the weld tips to close faster until:

  1. You have reached an impact speed you are happy with.
  . You have reached an acceptable decibel noise level.
  3. You see that the second exhaust and feedback sensor

illumination occur “just” as the weld tips contact.

Note:

This is a judgement call. If the flow control is set

too far open, then the weld block could result in welding
misfire causing the gun to fire before the weld tips close
fully. The reason this would occur is because the flow
control has been opened so much that all the air on the
front side of the cylinder has exhausted before the tips fully
close, thus negating the “low impact” benefit of the system.
To guarantee proper performance, find the setting where
the exhaust / illumination occurs “just” as the tips close,
and then adjust the flow control 1/ turn clockwise.

How to Set the Feedback Sensor Properly

The purpose of the feedback sensor is to provide an input
signal at the exact moment that full weld pressure has been
obtained at the weld tips. Traditionally this is achieved using
squeeze time. An experienced weld / electrical engineer
is needed to place the feedback sensor input into the PLC
program. The location of this input will vary depending on
the PLC manufacturer. Consult the robot manufacturer for
the proper input location.

Installation & Setup Instructions

Above is a sample PLC program where the feedback sensor
was placed during a typical install.  The location of the input
should be right before the weld start command.  Once the input
has been placed into the program, disconnect the sensor cable
from the feedback sensor.  This will allow you to determine
whether or not the input was placed in the correct spot.
Perform a trial run. If on the first weld, the weld tips close
and the robot stops, then the sensor input has been located
correctly in the program. If the robot continues to run, despite
the cable being disconnected, then the sensor input is not
correct. Review the location and then try the trial run again.

Note:

The weld block should perform the same whether the

robot is in manual or automatic mode.

Open

Flow Control

Close

Flow Control

5mm

Allen Wrench

Required For

Flow Control

Adjustment