18/03/2026
General Information section 3.0
In a Preliminary Welding Procedure Specification (pWPS), the General Information section provides the basic identification and reference details of the welding procedure. This section allows welders, inspectors, and engineers to easily identify the procedure being used.
📋 pWPS General Information (Typical Items):
✅Base Metals - are the actual workpieces (plates, pipes, structural members, etc.) that will be welded. The WPS clearly identifies them to ensure proper welding parameters and quality.
📌 Key Information Included in pWPS for Base Metals:
1. Material Specification
Example: ASTM A36, API 5L, ASME SA516
Defines the standard and chemical/mechanical properties
2. Material Grouping
Based on codes like ASME Section IX (P-Number)
Example:
P-No. 1 → Carbon steel
P-No. 8 → Stainless steel
3. Thickness Range
Minimum and maximum thickness qualified
Example: 6 mm to 25 mm
4. Material Type
Plate, pipe, tubing, etc.
✅Filler Metals - are materials (wire, rod, electrode) that melt during welding and fuse with the base metal to create a strong joint.
📌 Key Information Included in pWPS for Filler Metals:
1. Specification (Code Standard)
Example:
AWS A5.1 (Carbon steel electrodes)
AWS A5.18 (GMAW wires)
2. Classification
Identifies strength and usability
Examples:
E6013 (SMAW)
E7018 (Low hydrogen electrode)
ER70S-6 (GMAW/GTAW wire)
3. F-Number (ASME Section IX)
Group filler metals with similar usability
Example:
F-No. 3 → E6013
F-No. 4 → E7018
4. A-Number
Based on weld metal chemical composition
5. Diameter / Size
Example: 2.6 mm, 3.2 mm
6. Consumable Type
Covered electrode, solid wire, flux-cored wire, etc.
✅Shielding - refers to the method used to protect the weld pool from contamination (like oxygen, nitrogen, and moisture in the air) during welding.
📌 Types of Shielding in pWPS:
1. Shielding Gas (External Gas)
Used in processes like GMAW (MIG) and GTAW (TIG)
Common gases:
Argon (Ar) → Clean weld, used for TIG and aluminum
Carbon Dioxide (CO₂) → Deep pe*******on, cheaper
Argon + CO₂ mix → Balanced performance
Example (pWPS Entry):
Gas: Argon + 20% CO₂
Flow rate: 15–20 L/min
2. Flux Shielding
Used in SMAW (Stick) and FCAW (Flux-Cored)
Shielding comes from flux coating or core
Produces protective gas and slag during welding
Example:
E6013, E7018 electrodes (SMAW)
FCAW wire with flux core
3. Combination Shielding
Used in FCAW-G
Uses both flux + external gas
📌 Key Parameters in WPS (Shielding Section):
1. Type of shielding (Gas / Flux / Both)
Gas composition (%)
Flow rate (L/min or CFH)
Backing gas (if applicable, e.g., argon for root pass)
✅Technique - refers to the specific way the welder performs the weld to ensure consistency, quality, and compliance with the qualified procedure (PQR).
📌 Key Technique Variables in pWPS:
1. Stringer vs Weave Bead
Stringer bead → Straight pass (narrow, less heat input)
Weave bead → Side-to-side motion (wider bead, more coverage)
2. Electrode Manipulation
Angle (work angle & travel angle)
Motion (zigzag, circular, whipping, etc.)
3. Number of Passes / Layers
Single-pass or multi-pass welding
Includes:
Root pass
Fill passes
Cap pass
4. Cleaning Between Passes
Methods:
Chipping
Wire brushing
Grinding
5. Direction of Welding
Forehand (push) or Backhand (drag) technique
6. Arc Control - Affects pe*******on and stability
Arc length (short, medium, long)
✅Post Weld Heat Treatment—a controlled heating and cooling process applied after welding to improve the properties of the welded joint by:
Reducing residual stresses
Improving toughness
Preventing cracking (especially in thick or high-strength steels)
📌 Key PWHT Variables in WPS:
1. Temperature Range
Example: 580°C – 650°C (for carbon steel)
2. Holding Time (Soaking Time)
Depends on thickness
Typical: 1 hour per inch thickness
3. Heating Rate
Controlled to avoid thermal shock
Example: 100–200°C/hr
4. Cooling Rate
Slow and controlled (often inside furnace)
5. Method
Furnace heating
Local heating (electric resistance pads)
