Cooling Mechanical Systems Cooling Mechanical Systems Lesson Objectives
Cooling & Mechanical Systems
Cooling & Mechanical Systems Lesson Objectives When you finish this lesson you will understand: • System for cooling critical components • Systems for exerting electrode Force • Typical Applications Learning Activities 1. View Slides; 2. Read Notes, 3. Listen to lecture 4. Do on-line workbook 5. Do Homework Keywords Cooling System, Mechanical System, Fixed Stroke, Adjustable Stroke, Retractable Stroke, Valves, Rocker Arm, Press Type Welder, Servo Gun
Machines and Equipment • Cooling System • Mechanical System – Force generation system • Pneumatic/Hydraulic system • Motor or foot-operated system – Electrode application system • Rocker arm or pinch type • Press or direct action type • Portable system • Electrical System – Single-phase system – Single-phase rectified system – Three-phase rectified system – Frequency changer system – Frequency inverter system
Cooling System • Function: – Prevent overheating of the components of the welding machine • Components requiring cooling include: – The welding contactor (ignitron tubes or SCRs) – The welding transformer – The welding electrodes – Power cables (portable welding gun only)
A. Saabria, WE 651 Lab Report 1999
Machines and Equipment • Cooling System • Mechanical System – Force generation system • Pneumatic/Hydraulic system • Motor or foot-operated system – Electrode application system • • Rocker arm or pinch type Press or direct action type Portable system Servo System • Electrical System – Single-phase system – Single-phase rectified system – Three-phase rectified system – Frequency changer system – Frequency inverter system
Pneumatic/Hydraulic System Electrode Force: F=AP A K A A L P B (a) Fixed Stroke X R P B (b) Adjustable Stroke C H R L P B M (c) Adjustable, Retractable Stroke
Pneumatic Cylinder Valves Symbol Physical (a) Two-Way Valve Symbol Physical (b) Three-Way Valve with Single Acting Cylinder
Pneumatic Cylinder Valves (CONT. ) (c) Four-Way Valve with Double. Acting Cylinder P 1 P 2 (d) Four-Way, Five Port Valve with Double-Acting Cylinder
Electronic Pressure System Hirsch, R & Leibovitz, R, “Improved Weld Quality and Electrode Life in Resistance Welding” Practical Welding Today, Nov-Dec, 1997
Motor or Foot-Operated System X Rocker Arm Y Pivot Point Anvil x Spring Assembly F
Rocker Arm Machines X Y Air in [Reference: Resistance Welding Manual, p. 16 -2, RWMA]
Press Type Welding Machines [Reference: Resistance Welding Manual, p. 16 -5, RWMA]
C - Type Servo Spot Gun Slavick, “Overview of Servo-Driven Weldguns. . ” AWS Sheet Metal Conf. VIII, 1998
X - Type Servo Spot Gun Slavick, “Overview of Servo-Driven Weldguns. . ” AWS Sheet Metal Conf. VIII, 1998
Slavick, “Overview of Servo-Driven Weldguns. . ” AWS Sheet Metal Conf. VIII, 1998
Portable System [Reference: Automotive Manufacturing, April 1996, p. 5, SAE]
Mechanical Systems
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