Welding Machine Technical Manual

1. Working Principle

A welding machine utilizes the high-temperature arc generated by instantaneous short-circuiting of positive/negative electrodes to melt welding rod solder and base materials, achieving permanent bonding. Its core component is a high-power transformer that converts 220V/380V AC into low-voltage, high-current power (AC or DC).

2. Types & Classification

By Power Source:

AC Welding Machines: For steel structures, agricultural machinery
DC Welding Machines: For pressure vessels, pipelines, critical structures

Common Variants:

Type	Primary Applications	Key Features
Argon Arc (TIG)	Stainless steel, aluminum	Gas shielding prevents oxidation
CO₂ Shielded	Automotive, boilers	Deep penetration, high speed
Spot Welder	Sheet metal assembly	Precision joining
Laser Welder	Electronics, micro-welding	Ultra-high precision

3. Key Features

Advantages:

✔ Energy efficient (instant electric-heat conversion)
✔ Compact size with simple operation
✔ Creates high-strength, sealed joints
✔ Suitable for most metals (including dissimilar metals)

Limitations:

✖ Generates harmful UV/IR radiation and metal fumes
✖ Requires extensive safety precautions
✖ Poor weldability for high-carbon steels (risk of cracks)

4. Technical Specifications

Voltage Characteristics:

Open Circuit: 60-80V (safe ignition)
Working Voltage: 20-40V (stable arc maintenance)
Short Circuit: Near 0V (overcurrent protection)

Current Adjustment:

Coarse Adjustment: Changes coil taps (power-off operation)
Fine Adjustment: Modifies iron core/coil position (no-load operation)

5. Safety Protocols

Mandatory PPE:

Auto-darkening welding helmet (EN 175 certified)
Flame-resistant gloves and apron
Respiratory protection for confined spaces

Worksite Requirements:

▶ 10m clearance from flammables
▶ Proper ventilation (mechanical exhaust if needed)
▶ Insulated flooring in wet conditions

6. Maintenance Checklist

Daily:

Inspect cable insulation and connections
Verify cooling fan operation
Check gas lines for leaks (gas-shielded models)

Periodic:

Quarterly: Clean internal dust with dry compressed air
Biannually: Replace worn feed rollers (wire-feed models)
Annually: Calibrate current/voltage meters

7. Common Faults & Solutions

Symptom	Likely Cause	Solution
Overheating	Overload/short circuit	Reduce current/repair winding
Unstable arc	Loose core assembly	Tighten adjustment screws
Abnormal noise	Loose fasteners	Secure all mechanical joints

8. Industry Data (China 2012)

Total Production: 1.566 million units (+5.52% YoY)
Top Production Regions:
1. Zhejiang (36.9%)
2. Guangdong (27.49%)
3. Shanghai (19.38%)

9. Purchasing Guidelines

Essential Checks:

✅ Valid CCC certification mark
✅ Clear manufacturer labeling (rated current, duty cycle)
✅ Intact safety guards and insulation
✅ Smooth current adjustment mechanism