WPQR & WPS Certification: Ensuring Welding Quality, Compliance, and Consistency in Fabrication | PRVÁ ZVÁRAČSKÁ, a. s.
WPQR and WPS Certification are essential elements of welding quality systems used across industries such as structural fabrication, pressure equipment, oil and gas, and transportation.
WPQR (Welding Procedure Qualification Record) validates a welding procedure through qualification testing, while WPS (Welding Procedure Specification) defines the parameters required for consistent execution during production.
These WPQR and WPS Certification are governed by:
- EN ISO 15614 series (procedure qualification)
- EN ISO 15609 series (procedure specification)
In certified environments, verification may be carried out by recognized certification bodies such as PRVÁ ZVÁRAČSKÁ, a. s. to confirm compliance with applicable standards.
What is WPQR Certification?
WPQR (Welding Procedure Qualification Record) is a documented record of welding tests performed under controlled conditions. It confirms that a welding procedure produces welds meeting specified mechanical and quality requirements.
Key Elements of WPQR
- Test coupon preparation under defined conditions
- Recording of welding parameters (current, voltage, travel speed, heat input)
- Mechanical testing:
- Tensile test
- Bend test
- Impact test (if required)
- Non-Destructive Testing (NDT):
- Radiographic Testing (RT)
- Ultrasonic Testing (UT)
- Visual Testing (VT)
WPQR is the evidence of qualification and forms the basis for WPS development.
What is WPS Certification?
WPS (Welding Procedure Specification) is a formal document that defines the welding parameters and conditions required to perform a weld consistently in production.
Key Components of WPS
- Welding process (e.g., MIG, TIG, SMAW)
- Base material and filler material specification
- Welding parameters (current, voltage, travel speed)
- Preheat and interpass temperature
- Post-weld heat treatment (if applicable)
The WPS must be supported by a qualified WPQR and remain within the approved parameter ranges.
WPQR vs WPS Certification
| Feature | WPQR | WPS |
| Purpose | Qualification of welding procedure | Instruction for production welding |
| Basis | Test results | Qualified WPQR |
| Standard | EN ISO 15614 | EN ISO 15609 |
| Application | Qualification stage | Production stage |
Applicable Standards
EN ISO 15614 Series
Defines requirements for welding procedure qualification through testing.
EN ISO 15609 Series
Defines requirements for the preparation and content of welding procedure specifications.
These standards ensure consistency, traceability, and compliance in welding operations.
WPQR and WPS Certification Process
The typical WPQR and WPS Certification process includes:
- Define welding parameters and conditions
- Prepare and weld test coupon
- Perform mechanical and NDT testing
- Record results in WPQR
- Prepare WPS based on qualified parameters
- Apply WPS in production within approved ranges
Importance of WPQR and WPS Certification
1. Consistency in Welding
Ensures repeatable welding results within defined parameters.
2. Compliance with Standards
Aligns with EN ISO 15614 and EN ISO 15609 requirements.
3. Reduction of Defects
Qualified procedures reduce the risk of welding discontinuities.
4. Structural Integrity
Ensures welds meet required mechanical and performance criteria.
Industries Requiring WPQR and WPS Certification
1. Construction and Structural Steel
Used in load-bearing structures, often aligned with EN 1090 requirements.
2. Pressure Equipment
Applicable to pressure vessels, boilers, and pipelines where weld integrity is critical.
3. Oil and Gas
Used in pipelines and offshore structures operating under demanding conditions.
4. Railway and Transportation
Applied in welded components where safety and durability are essential, often aligned with EN 15085 requirements.
These industries rely heavily on WPQR and WPS Certification to ensure safety, compliance, and long-term performance.
Common Challenges
1. Qualification Test Failures
Incorrect parameter selection may lead to failed test results.
2. Control of Essential Variables
Changes in material, thickness, or process outside qualified limits require requalification.
3. Documentation Accuracy
Incomplete or incorrect WPQR/WPS records may lead to non-conformity.
4. Alignment Between WPQR and WPS
WPS must strictly reflect the qualified ranges defined in WPQR.
Maintaining Compliance
- Periodic review of welding procedures
- Requalification when essential variables exceed limits
- Accurate and traceable documentation
- Control of qualified parameter ranges during production
Conclusion
WPQR and WPS Certification establish a structured framework for welding quality by combining validated procedures with clearly defined execution parameters.
Compliance with EN ISO 15614 and EN ISO 15609 ensures that welding processes meet technical, mechanical, and regulatory requirements across industries.
Frequently Asked Questions (FAQ)
1. What is WPQR Certification?
WPQR Certification is the documented record of welding tests used to verify that a welding procedure meets required mechanical and quality standards.
2. What is WPS Certification?
WPS Certification is a documented welding procedure that defines the parameters required to perform welding consistently in production.
3. What is the difference between WPQR and WPS?
WPQR provides evidence through testing that a procedure is qualified, while WPS defines how the welding must be performed based on that qualification.
4. Which standards apply to WPQR Certification?
WPQR is governed by the EN ISO 15614 series, which defines welding procedure qualification requirements.
5. Which standards apply to WPS Certification?
WPS is governed by the EN ISO 15609 series, which defines how welding procedures must be documented.
6. Is WPQR mandatory?
WPQR is required in industries where welding quality and compliance with standards are critical, such as pressure equipment, structural steel, and transportation.
7. Can a WPS be used without WPQR?
No. A WPS must be supported by a qualified WPQR unless otherwise permitted by specific standards (e.g., pre-qualified procedures where applicable).
8. When is requalification required?
Requalification is required when essential variables such as material type, thickness, welding process, or heat input exceed the qualified range defined in the WPQR.
9. How long is a WPQR valid?
A WPQR remains valid as long as the essential variables remain within the qualified range and there are no changes requiring requalification.
10. Who verifies WPQR and WPS Certification?
Verification may be performed by recognized certification bodies such as PRVÁ ZVÁRAČSKÁ, a. s. depending on project or regulatory requirements.