Product Overview

This document provides comprehensive technical details on TECNA's rocker arm spot welders, available in both foot-operated and pneumatic versions with power ratings ranging from 16 to 25 kVA. These machines are designed for versatile spot welding applications, emphasizing ergonomic design, operator convenience, and advanced control features.

1. Product Description and Ergonomics

TECNA spot welders feature a stationary column frame designed for ergonomic operation. The control unit is positioned frontally for easy monitoring of welding parameters. Pneumatic controls and compressed air pressure gauges are conveniently located at the top for straightforward adjustment and reading.

2. Technical Specifications

• Adjustable Arms: Length-adjustable to accommodate various welding tasks.
• Electrode Holders: Constructed from chrome-copper for durability and long life; suitable for both straight and angled mounting.
• Electrode Stroke: Adjustable to meet different welding requirements.
• Transformer: Epoxy resin encapsulated for enhanced durability; water cooling applied to transformer, arms, and electrodes to maintain stable performance.
• Control Unit: Microprocessor-based TECNA TE90 ensures precise welding control.

3. Foot-Operated Welders

• Adjustable electrode force for tailored welding pressure.
• Microswitch triggers welding cycle upon reaching preset force.
• Adjustable foot pedal length enhances operator comfort.

4. Pneumatic Welders

• Equipped with lubrication-free pneumatic cylinders to prevent oil mist emission.
• Electrode force adjustable via filter-reducer group and pressure gauge.
• Semi-automatic condensate drainage system included for maintenance ease.
• Speed regulators control electrode opening and closing speeds.
• Shock absorbers and air discharge silencers improve operational smoothness and reduce noise.
• Two-stage electric foot pedal supports normal single-cycle, automatic operation, and clamping-only mode for precise positioning.
• Optional second two-stage foot pedal (item 70284) allows switching between two different time-current settings, facilitating multiple weld types on the same workpiece.

5. Accessories and Options

• Various reduced-size brass and copper arms with different electrode tips and frontal electrodes for task-specific customization.
• Adjustable large-gap arm assembly (item 70364) enables modification of arm spacing, affecting welding current (larger gap reduces current).
• Additional foot pedal (item 70379) for dual program operation.
• Water-cooled electrodes available to enhance performance and durability.

6. Performance Parameters

Arm depth is adjustable up to 320 mm to suit different working conditions. Arm gap ranges from a minimum of 125 mm to a maximum of 420 mm, with intermediate settings possible. Notably, increasing the arm gap reduces the welding current, allowing fine-tuning of welding intensity.

7. Control System Features (Pneumatic Models)

• Synchronous Thyristor Control: Phase angle control of welding current for precise regulation.
• Slope and Pulse Functions: Controlled current rise and pulsation optimize weld quality.
• Twin Presettings: Two independent time-current programs selectable via separate foot pedals.
• Programming Interface: Simplified with a selector switch for WELD / NO WELD modes.
• Operational Modes: Supports single cycle and automatic repeat cycle.
• Secondary Current Compensation: Maintains welding consistency by adjusting for current variations.
• First Phase Shift Delay: Adjustable to optimize mains power absorption balance.
• Autoretain Disabling: Available for foot-operated machines to prevent self-holding cycles, enhancing safety.

8. LED Indicators and Diagnostics

• ON: Indicates machine power status.
• START: Signals activation of main foot pedal cycle.
• START 2: Signals activation of additional foot pedal cycle.
• AUX: Indicates clamping initiation without welding.
• CURRENT: Shows SCR firing and welding current flow.
• SOLENOID VALVE: Indicates activation of pneumatic control valve.

9. Operational Notes and Best Practices

• Carefully adjust electrode force to match welding requirements for optimal results.
• Utilize ergonomic features such as adjustable arms and foot pedals to improve operator comfort and efficiency.
• Leverage the two-stage foot pedal and optional second pedal to perform complex welding tasks requiring different settings on the same workpiece.
• Regularly monitor and adjust pneumatic controls and pressure gauges to maintain consistent welding quality.
• Employ water cooling for transformer, arms, and electrodes to ensure machine longevity and stable performance.
• Disable autoretain function in foot-operated models to enhance safety and control.
• Adjust first ignition timing to optimize electrical load balance on the power supply.

10. Manufacturer Information and Disclaimer

TECNA S.p.A. reserves the right to modify product specifications without prior notice. For inquiries and support, contact:
Via Meucci, 27, 40024 Castel S. Pietro Terme, Bologna, Italy
Phone: +39.051.6954411
Fax: +39.051.6954490
Website: www.tecna.net
Email: [email protected] / [email protected]

Summary

TECNA's rocker arm spot welders combine ergonomic design, flexible mechanical adjustments, and advanced microprocessor control to deliver reliable and versatile spot welding solutions. The availability of both foot-operated and pneumatic models, along with a comprehensive range of accessories and programmable control features, allows customization to diverse industrial welding needs, ensuring operator comfort, precise control, and consistent welding quality.