ASME PCC-2 Post Construction Specifications - Episode 2 (Part 2: Welding Repairs)
Introduction to Athabasca Engineering Solutions
Overview of AES Services
- Chris Kurzick introduces himself as the principal engineer at Athabasca Engineering Solutions (AES).
- AES provides various services including third-party value evaluations, training and certification, and equipment re-rating.
Continuing PCC2 Weld Repairs Presentation
Focus on Article Discussions
- The presentation continues with part two of the discussions on PCC2 weld repairs, covering 16 articles in total.
Article 209: Alternatives to Post Weld Heat Treating
Situations Requiring Alternative Methods
- Discusses scenarios where post-weld heat treating is not feasible, such as when dealing with live lines or chrome moly alloys.
Temper Bead Welding Technique
- Introduces temper bead welding, a method developed in the nuclear industry for managing heat input during welding processes.
Article 210: In-Service Welding Concerns
Key Considerations for Welding on Pressurized Components
- Highlights concerns about burning through pipe walls and hydrogen cracking due to local heating during welding.
Techniques for Control
- Emphasizes the importance of controlling cooling rates and using techniques like temper bead welding to mitigate risks.
Limitations of In-Service Welding Techniques
Applicability Restrictions
- Notes that these techniques are primarily applicable to carbon steel and may not be suitable for chrome moly or stainless steel.
Article 211: Weld Build-Up and Overlay Restoration
Types of Restoration Processes
- Describes three main sections: weld overlay for corrosion resistance, weld build-up for restoring worn surfaces, and clad restoration methods.
Application Context
- Indicates that while focused on refineries, these methods can also be adapted for mining applications.
Article 212: Using Weld Patches with Fillet Welds
Repair Methodology
- Explains the use of fillet weld patches along plate edges as a repair method similar to article 207 but focusing solely on fillet weld applications.
Challenges in Matching Contours
- Discusses the difficulty in accurately matching contours when repairing wall thinning across various shapes.
Threaded or Welded Plug Repairs
Flaw Removal Process
- Details procedures involving drilling out defects followed by inserting solid or threaded plugs sealed with welding.
Access Considerations
- Mentions this method's utility in gaining access for inspection purposes within components.
Field Heat Treating Hazards
Risks Associated with Heat Treatment
- Warn about hazards like structural instability during heat treatment processes which could lead to material degradation or collapse.
Recommendations for Safety Measures
- Suggest strategies to manage thermal expansion issues and ensure structural integrity during field operations.
Article 215: Welding Repair Considerations for Chrome Moly Vessels
Challenges in Chrome Moly Welding
Overview of Deterioration Mechanisms and Repair Methods
Common Issues in Turnarounds
- The speaker discusses common issues encountered during turnarounds, particularly focusing on skirt attachment welds. They mention the availability of extensive resources from API (American Petroleum Institute) for further information.
- Key problems highlighted include well seam failure, hydrogen-assisted cracking, and hydrogen cracking, which are significant concerns in the industry.
High-Level Overview of Deterioration Mechanisms
- A high-level overview is provided regarding deterioration mechanisms that should be considered when developing a detailed repair plan.
- The discussion includes examples of damage to guide professionals in identifying issues effectively.
Summary of Repair Methods
- The article summarizes various repair methods and offers a roadmap for next steps in addressing identified issues.
Welded Hot Taps in Pressure Equipment
- Article 216 focuses on welded hot taps used in pressure equipment or pipelines, explaining the process of welding a tee or fitting onto a pipeline before drilling into it with specialized equipment.
Considerations for Carbon Steel Lines
- PCC2 provides advice specifically for carbon steel lines, emphasizing factors like flow rates that can affect weld cooling during operations.
- It is important to maintain minimum tank levels as per API 653 guidelines to avoid overstressing the shell during hot tap operations.
Calculations Required During Welding Operations
- When welding onto pipes, calculations such as burn-through calculations are necessary to ensure sufficient material remains after welding to maintain structural integrity.
- External pressure calculations must also be performed prior to pressurizing connections post-welding to prevent local collapse of the pipe.
Detailed Codes and Further Information