Aramco Piping QC Notes [PDF] – PDFYAR

This article is about Aramco Piping QC Notes for Aramco CBT Examination for International Projects of Plants and oil and gas industry.

Aramco Piping QC Notes

1. Can Teflon tape be used prior to seal welding?

According to SAES-L-110, Teflon tape should not be used prior to seal welding. Teflon tape is a thread sealant commonly used in threaded pipe connections to prevent leaks. However, when it comes to seal welding, it is important to ensure proper fusion and penetration between the pipe and fitting. Teflon tape can interfere with the welding process and compromise the integrity of the weld joint. Therefore, it is recommended to avoid using Teflon tape before seal welding and instead follow the appropriate welding procedures and techniques specified in the relevant standards and specifications.

2. How many threads can be visible after seal welding threaded joints?

As per SAES-W-011, after seal welding threaded joints, all exposed threads should be covered by the weld metal. Therefore, no threads should be visible after the seal welding process. The purpose of seal welding is to ensure a leak-tight joint by effectively sealing off the threaded connection.

3. What is the gap requirement for socket welds for new construction?

As per ASME B31.3, Fig. 328.5.2C, the recommended gap requirement for socket welds in new construction is typically 1.5mm to 3mm (1/16 inch to 1/8 inch). This gap allows for proper penetration and fusion during the welding process. It is important to maintain the specified gap to ensure a strong and reliable socket weld joint.

4. Give examples of unique support details that allow piping freedom of movement for thermal expansion?

Here are some examples of unique support details that allow piping freedom of movement for thermal expansion:

1. Guide Support: These supports are designed to guide the movement of the piping system in a specific direction while restricting movement in other directions. They typically consist of guide rods or channels that allow axial movement while preventing lateral movement.
2. Moving Saddle Support: This type of support allows the pipe to move freely in the axial direction while providing support at specific intervals. It typically consists of a sliding saddle that allows the pipe to expand and contract without restraint.
3. Expansion Balloons: Expansion balloons or flexible expansion joints are used to absorb thermal expansion and contraction. They are designed to accommodate the movement of the piping system and provide flexibility by using a bellows-like structure.
4. Shoe Support: Shoe supports are designed to support the pipe while allowing movement in a specific direction. They usually consist of a base plate and a sliding shoe that allows for longitudinal movement of the pipe.
5. Spring Loaded Support: These supports use springs to provide a constant force that opposes the thermal expansion or contraction of the pipe. The springs allow the pipe to move freely while maintaining a consistent load on the system.

5. When you will apply 24 hours recorded hydro test?

The 24-hour recorded hydro test is applied in specific situations where it is not possible to keep the joints exposed during testing due to justifiable safety reasons, such as when conducting a hydrostatic test on an underground (UG) pipeline that needs to be backfilled. In such cases, the joints are covered, and the test is extended to a 24-hour duration.

According to SAES-L-150 para 7.4.2, if it is necessary to backfill the UG line and the joints cannot remain exposed, a 24-hour recorded hydro test is conducted. This extended duration allows for a thorough evaluation of the system’s integrity and ensures that any potential leaks or failures can be identified and addressed.

The 24-hour recorded hydro test provides an additional level of assurance regarding the performance and safety of the piping system, compensating for the inability to visually inspect the joints during the testing process.

6. Difference between carbon steel and stainless steel?

The main difference between carbon steel (CS) and stainless steel (SS) lies in their composition and properties:

1. Composition: Carbon steel primarily consists of iron and carbon, with a maximum carbon content of 0.3%. Stainless steel, on the other hand, contains a minimum of 12% chromium, along with varying amounts of other elements such as nickel, molybdenum, and manganese.
2. Corrosion Resistance: Carbon steel is susceptible to corrosion and rusting when exposed to moisture and certain environments. Stainless steel, with its high chromium content, offers excellent corrosion resistance and is more resistant to rust and staining. It is suitable for use in corrosive environments.
3. Temperature Range: Carbon steel is suitable for non-corrosive services up to a maximum temperature of around 350 degrees Celsius. Stainless steel, with its higher chromium content and alloying elements, can withstand more extreme temperatures, making it suitable for cryogenic applications as well as high-temperature environments.
4. Cost: Carbon steel is generally less expensive than stainless steel due to the lower cost of raw materials and simpler manufacturing processes. Stainless steel, with its additional alloying elements, is costlier to produce.
5. Mechanical Properties: Carbon steel has good mechanical properties and is often used for structural applications. Stainless steel, depending on its grade and heat treatment, offers a wide range of mechanical properties, including high strength, toughness, and ductility.

Overall, carbon steel is commonly used in applications where cost is a significant factor and where corrosion resistance is not critical. Stainless steel is preferred for applications requiring corrosion resistance, high or low-temperature performance, and when a higher level of material durability and aesthetics is desired, even though it comes at a higher cost.

7. Write Down Differences between RT & UT?

The main differences between Radiographic Testing (RT) and Ultrasonic Testing (UT) are as follows:

Radiographic Testing (RT):

1. Method: RT uses X-ray or Gamma ray radiation to penetrate the material being inspected. The radiation is passed through the object, and a film or digital detector is used to capture the resulting image.
2. Defect Detection: RT primarily detects volumetric defects such as internal voids, inclusions, and porosity. It can also identify planar defects such as cracks and weld discontinuities.
3. Defect Visibility: RT provides a two-dimensional image of the internal structure of the material, making it useful for visualizing the shape and size of defects. However, it may not accurately determine the precise location or depth of the defect.
4. Material Compatibility: RT can be used on a wide range of materials, including metals, composites, and ceramics.
5. Limitations: RT is not suitable for materials that are highly absorbing or scatter radiation, and it requires proper safety precautions due to the use of ionizing radiation.

Ultrasonic Testing (UT):

1. Method: UT uses high-frequency sound waves to inspect materials. A transducer sends ultrasonic waves into the material, and the reflected waves are analyzed to detect defects.
2. Defect Detection: UT is capable of detecting both planar defects, such as cracks, and volumetric defects, such as voids and inclusions.
3. Defect Visibility: UT provides real-time information about the location, size, and orientation of defects. It can display the results as a cross-sectional image of the material.
4. Material Compatibility: UT is applicable to a wide range of materials, including metals, plastics, composites, and ceramics.
5. Limitations: UT requires direct contact or coupling between the transducer and the material being tested. It may not be suitable for materials with rough surfaces or those that absorb or scatter sound waves excessively.

In summary, RT uses X-ray or Gamma rays to produce a two-dimensional image of the internal structure of the material, primarily detecting volumetric defects. UT uses high-frequency sound waves to detect both planar and volumetric defects and provides real-time information about the defects, although it may not accurately determine their precise location or depth.

8. Write down Differences between PT & MT?

The main differences between Penetrant Testing (PT) and Magnetic Particle Testing (MT) are as follows:

Penetrant Testing (PT):

1. Method: PT involves applying a liquid penetrant (dye) to the surface of the material being inspected. After a specified dwell time, the excess penetrant is removed, and a developer is applied to draw out any penetrant that has seeped into surface-breaking defects.
2. Defect Detection: PT is primarily used to detect surface-breaking defects such as cracks, porosity, and laps. It is not effective for detecting subsurface defects or defects in non-porous materials.
3. Material Compatibility: PT can be used on both ferromagnetic and non-ferromagnetic materials, making it versatile for a wide range of applications.
4. Time: PT typically requires more time for testing and inspection compared to MT.

Magnetic Particle Testing (MT):

1. Method: MT involves creating a magnetic field in the material being inspected. Magnetic particles (either dry or suspended in a liquid) are applied to the surface, and they align themselves with the magnetic field. Any surface or near-surface defects disrupt the magnetic field, causing the particles to cluster and form visible indications.
2. Defect Detection: MT is used to detect surface and near-surface defects in ferromagnetic materials. It can detect defects such as cracks, porosity, and other discontinuities that interrupt the magnetic field.
3. Material Compatibility: MT is applicable only to ferromagnetic materials, which include iron, nickel, and cobalt-based alloys. Non-ferromagnetic materials are not suitable for MT.
4. Time: MT typically takes less time for testing and inspection compared to PT.

In summary, PT is used to detect surface-breaking defects in both ferromagnetic and non-ferromagnetic materials, while MT is used to detect surface and near-surface defects specifically in ferromagnetic materials. PT requires more time and is applicable to a wider range of materials, whereas MT is quicker but limited to ferromagnetic materials.

9. How do you control material in fabrication shop?

To control material in a fabrication shop, the following measures can be implemented:

1. Material Marking: All materials should have their material specification and grade stamped or stenciled on them. Additionally, they should be clearly marked with a permanent marker for easy identification.
2. Traceability: All materials should be traceable to the Material Test Certificate (MTC) from approved vendors. Heat numbers, which indicate the batch of material, should be recorded and maintained for traceability purposes. No material substitution should be allowed without proper approval from the company.
3. Storage and Stacking: Materials should be stored and stacked separately based on their material grade. This ensures that materials are not mixed up and can be easily accessed when needed.
4. Heat Number Transfer: Before cutting pipes, the heat number should be transferred or marked on the pipes. This ensures that the traceability of materials is maintained throughout the fabrication process.
5. Color Coding: Implementing a color coding system can aid in material traceability. Each material grade can be assigned a specific color, which can be marked on the materials or their containers. This helps in quickly identifying and segregating materials based on their grade.

By implementing these measures, the fabrication shop can effectively control and manage materials, ensuring traceability, preventing material substitution, and maintaining proper organization and identification of materials throughout the fabrication process.

10. Write inspection items during valve installation?

During valve installation, the following inspection items should be checked:

1. Valve Type: Ensure that the correct valve type is installed at the designated location. Verify that it matches the specifications and requirements specified in the project documentation.
2. Valve Test Certificate: Check for the availability and validity of the valve test certificate. This ensures that the valve has undergone proper testing and meets the required standards.
3. Valve Tag: Verify that the valve is tagged correctly according to the Piping and Instrumentation Diagram (P&ID). The tag should match the identification number or code specified on the P&ID.
4. Valve Direction of Flow: Ensure that the valve is installed in the correct direction of flow as indicated on the P&ID. Check the arrow or flow direction indicator on the valve and align it with the flow direction specified on the P&ID.
5. Gasket Bolts: Inspect the gasket bolts to ensure they match the specifications provided in the isometric drawing. Check for the correct size, type, and quantity of bolts used for gasket installation.
6. Handle Direction: Verify that the valve handle is properly positioned according to the required open and closed positions. The handle should be aligned with the designated flow direction and rotation for operation.
7. Chain Wheel: If applicable, check if a chain wheel is installed on the valve for manual operation. Ensure that it is properly attached and secured, allowing for easy operation when required.
8. Valve Flange Face Condition: Inspect the valve flange face condition to ensure it is clean, free from any damage or deformities, and ready for proper gasket sealing. Check for any signs of corrosion, roughness, or irregularities that may affect the valve’s performance.

By conducting these inspection checks during valve installation, you can ensure that the valves are installed correctly, comply with specifications, and are ready for efficient and reliable operation within the piping system.

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