This article explains the limitations that apply to the selection of various valves falling under the purview of Saudi Aramco Materials System (SAMS) Class 04. This classification typically encompasses a wide range of valve types, including ball, butterfly, check, choke, diaphragm, gate, globe, needle, and plug valves. These valves serve functions such as on-off control, manual control service, and preventing reverse flow, as needed within the industry.
To read full document of SAES-L-108 and download.
SAES-L-108Valves Selection
However, it’s essential to clarify the scope by highlighting what falls outside of it. This article specifically excludes the following:
a) Control, Safety-Relief, Relief, Surge Relief, Solenoid, Pilot Valves: Valves that fall under SAMS Class 34 are not covered within the scope of this article. These valves are often associated with more specialized functions related to control, safety, and relief mechanisms.
b) Flues, Chimneys, Air Conditioning, Ventilation Ducts: Valves used in applications involving flues and chimneys, as well as those used in air conditioning and ventilation ducts, are not addressed in this article. These contexts usually have distinct requirements beyond the scope of SAMS Class 04.
c) Drilling and Wellhead Valves: Valves categorized under SAMS Class 45, which pertain to drilling and wellhead applications, are excluded from the coverage of this article. These valves play a crucial role in the upstream segment of the industry.
It’s important to note that this Standard complements the stipulations outlined in ASME B31, which is the Code for Pressure Piping. The ASME B31 provides a framework of guidelines for the design, construction, inspection, and testing of piping systems, further underlining the technical basis of the information presented in this article.
In essence, this article serves as a guide for making informed decisions about the selection of valves categorized under SAMS Class 04. It helps stakeholders in the oil and gas industry understand the appropriate context for using these valves, while also outlining the boundaries of their application. The exclusions mentioned in the article provide clarity and prevent any misinterpretation or misuse of the specified valve types. By adhering to these limitations and consulting the relevant codes and standards, industry professionals can ensure the safe and effective operation of their systems. This article also explain most expects of SAES-L-108.
International Codes and Standards for Valves Selection
American National Standards Institute/Fluid Controls Institute
ANSI/FCI 70.2 – Control Valve Seat Leakage
American Petroleum Institute
API SPEC 6A – Specification for Wellhead and Christmas Tree Equipment
API SPEC 6D – Specification for Pipeline Valves
API SPEC 6FA – Specification for Fire Test for Valves
API STD 598 – Valve Inspection and Testing
API STD 602 – Compact Steel Gate Valves – Flanged, Threaded, Welding, and Extended-Body Ends
API STD 607 – Fire Test for Soft Seated Quarter-Turn Valves
API STD 609 – Butterfly Valves, Lug-Type and Wafer-Type
American Society of Mechanical Engineers
ASME B16.5 – Steel Pipe Flanges and Flanged Fittings
ASME B16.34 – Valves – Flanged, Threaded, and Welding End
ASME B31 – Code for Pressure Piping
British Standards Institution
BS 6755 – Testing of Valves
Manufacturers Standardization Society of the Valve and Fittings Industry, Inc.
MSS SP-45 Bypass and Drain Connection Standard
National Association of Corrosion Engineers/International Standardization Organization
NACE MR0175/ISO 15156 Petroleum and Natural Gas Industries – Materials for Use in H2S Containing Environments in Oil and Gas Production.
Selection of Valves
Valves are integral components in various industries, from oil and gas to manufacturing. These devices control the flow of liquids or gases and play a crucial role in ensuring the safety and efficiency of operations. The procurement of valves is a meticulous process governed by standards and regulations, and in this article, we’ll explore the key aspects of valve procurement, particularly in the context of the stringent guidelines set forth by Saudi Aramco.
Approved Manufacturers and Strict Governance
In the world of valve procurement, not all manufacturers are created equal. Saudi Aramco, a major player in the energy industry, enforces strict regulations regarding the source of valves. According to SAES-L-102, valves must be purchased from approved manufacturers listed in this document. This list serves as a seal of quality and reliability, assuring that the valves meet the required standards for performance and safety.
Moreover, any deviation from purchasing valves from these approved manufacturers is governed by specific provisions outlined in the document. This ensures that even if there is a need to source valves from alternative manufacturers, the quality and integrity of the equipment remain uncompromised.
Limitations on Materials, Types, and Sizes
The selection of valves isn’t a free-for-all. SAES-L-102 dictates that valve selection should generally adhere to the materials, types, and sizes listed in SAMS Class 04. This limitation exists unless there’s a genuine reason to deviate. The document emphasizes the importance of referencing Specifications (SAMSS’s) listed in Section 3 of the standard in all requisitions.
However, there are instances where a valve that is similar to those covered by a SAMSS but differs in specific design, construction, materials, or performance characteristics is needed. In such cases, it’s crucial to include the SAMSS in the purchase requisition, along with the required modifications. These modifications must align with all other Mandatory Saudi Aramco Engineering Requirements, ensuring that safety and performance aren’t compromised.
Documentation and Field Tests
Valve procurement is accompanied by rigorous documentation requirements. Requisitions for all valves (excluding API SPEC 6A 10000 psi valves 2-1/16 inches and larger) should reference 04-SAMSS-035, General Requirements for Valves, and 04-SAMSS-048, Valve Inspection & Testing Requirements. These references ensure that the procured valves adhere to the necessary standards.
Form 6233-1-ENG, Valve Data Sheet, is a critical document in the valve procurement process. It must be completed and attached to every non-SAMS class 04 valve purchase requisition. This data sheet serves as a comprehensive record of the valve’s specifications and ensures that all relevant details are accounted for.
Field Tests: Ensuring Reliability
In the demanding environments of industries like oil and gas, the reliability of valves is non-negotiable. Field tests play a pivotal role in verifying the integrity of valves before they are put into service. Several key aspects of field testing are outlined in SAES-L-102:
1. Testing Location:
The proponent, the entity responsible for the project or operation, specifies the testing location. This ensures that the tests are conducted under conditions relevant to the specific application.
2. Isolation Service:
Valves designated for isolation service, as specified by the proponent, undergo high-pressure hydrostatic seat tests before installation in the line. These tests simulate the extreme conditions these valves will face in the field.
3. Alternative Testing for Flare System Valves:
In some cases, a low-pressure pneumatic seat test at 35 kPa (5 psig) can be substituted for the high-pressure hydrostatic seat test for flare system valves. This provides flexibility while maintaining safety standards.
4. Exemptions for Small Valves:
Buttweld and socketweld end valves in nominal pipe size (NPS) 2 inches and smaller are exempt from certain field testing requirements. This recognizes that the testing process may not be practical or necessary for smaller valves.
5. Stringent Leakage Criteria:
For resilient (soft) seated isolation valves, the leakage criteria are exceptionally stringent, with zero leakage being the standard. This level of reliability is essential to prevent leaks and ensure safety.
Seat Leakage Criteria and Compliance
The use of ANSI FCI 70.2 to specify seat leakage criteria is a standard practice in many industries. However, SAES-L-102 explicitly states that this practice is not permitted without the specific approval of the Chairman of the Valves Standards Committee. This highlights the importance of adhering to Saudi Aramco’s specific guidelines and standards in valve procurement.
Trim Material and Its Scope
Lastly, it’s essential to understand the concept of “trim material.” Trim material encompasses various components of the valve, including the stem, body, closure seating surfaces, bushings, pins, springs, guides, and any other small parts that come into contact with the service fluid. These components play a crucial role in the valve’s performance and longevity, making their material selection a critical consideration.
In conclusion, the procurement of valves in industries like oil and gas is a highly regulated and meticulous process. Compliance with standards such as SAES-L-102 is not only a requirement but a fundamental aspect of ensuring the safety, reliability, and integrity of operations. These stringent guidelines, from approved manufacturers.
General Design Limitations of Valves
Valves are the unsung heroes of many industrial processes, controlling the flow of fluids in pipelines and systems. However, not all valves are created equal, and the design limitations of these crucial components play a pivotal role in ensuring their safety and performance. In this article, we’ll delve into the intricate world of valve design limitations, particularly in the context of Saudi Aramco’s stringent guidelines.
Bonnet and Cover Limitations
1. Pressure Seal Bonnets
- Service Restriction: Pressure seal bonnet valves are designed for use in steam or other clean, non-corrosive services. They may be used in other services only if the body’s bonnet sealing area has been inlaid with a suitable material.
2. Split Ring Retained Bonnets
- Special Approval: Bonnets retained by split rings and sealed by means of an O-ring or a seal-welded membrane can only be used after receiving approval from the Chairman of the Valves Standards Committee.
3. Welded Bonnet Valves in Hydrocarbon Services
- Size Restriction: The use of welded bonnet valves in hydrocarbon services is limited to NPS 4 inch and smaller, subject to approval by the Manager of the responsible operating department.
4. Screwed Bonnet and Screwed Body Valves
- Service Restriction: These valves are prohibited in hydrocarbon or hazardous material services unless the bonnets and body end connections are tack welded to the body or provided with locking pins.
5. Straight-Thru Union Body Check Valves
- Specific Application: These valves are designed for use only in portions of piping systems where pipe unions are permissible.
6. Union Bonnet Valves
- Service Restriction: Union bonnet valves are not to be used in any hydrocarbon or hazardous material services.
End Connection Requirements
1. Applicability of SAES-L-110
- Universal Application: The requirements outlined in SAES-L-110 are applicable to all valves, ensuring consistency and quality in valve design.
2. Integral Flanged Valve Bodies
- Specific Approval: The use of integral flanged valve bodies with tapped bolt holes is generally discouraged, but exceptions can be made with the approval of the Proponent and the Chairman of the Valves Standards Committee. This does not apply to lug-type valves.
3. Repairable Valves
- NPS 8 Inch and Larger: Critical valves, welding end valves, and others that cannot be removed from the line without serious difficulty (e.g., restrained pipelines) and are NPS 8 inch and larger should be of a type that is repairable in the line (top-entry). This, too, requires specific approval by the Chairman of the Valves Standards Committee.
Ratings and Pressure-Temperature Relationships
1. Soft Seated Valves
- Temperature Considerations: Valves utilizing soft seats may not necessarily follow ASME B16.5 or other industry-standard pressure/temperature relationships at temperatures above 38°C. Specific Vendor’s literature should be consulted for higher-temperature ratings.
2. Minimum Body Rating for Small Valves
- Hydrocarbon Services: In hydrocarbon services, threaded and socketweld end NPS 2 inch and smaller valves must have a minimum body rating equivalent to API STD 602 Class 800.
Valve Sizes
Size Limitations
- Consistency with Pipe Sizes: Valves are subject to the same size limitations specified for pipes in SAES-L-136.
Stem Packing and Seal Materials
Stem Packing Restrictions
- Hydrocarbon Services: Isolation valves NPS 3 inch and larger in hydrocarbon services must not be provided with pure polymer/elastomer stem packing or stem seals unless they are qualified as fire-safe. Exceptions can be made as permitted by an approved SAMSS.
Actuators
1. Power Actuation
- Review Required: The need for power actuation of all valves NPS 12 inch and larger in all pressure classes must be reviewed with the responsible operating organization.
2. Chainwheel Operation
- Limitations: Chainwheel operation should not be provided for emergency isolation valves or valves with threaded body connections.
Installation and Use of Gate Valves
1. Stem Orientation
- Horizontal Stem Placement: Gate valves with back-seats should not be installed with their stems below the horizontal, except in specific cases such as clean services, isolation valves in pressure relief and flare system piping, or utility services. The classification of critical and non-critical valves should be specified by the proponent and approved by the Chairman of the Valves Standards Committee.
Seal Welding of Threaded Connections
1. Seal Welding Requirement
- Universal Application: All threaded connections on valve bodies and associated piping must be seal welded.
2. Compliance with SAES-L-110
- Welding Standards: Seal welding procedures must adhere to the general requirements outlined in SAES-L-110.
Coating Restrictions
Internal Coating of Steel Gate Valves
- Wedge Considerations: The body of steel gate valves must not be internally coated unless the wedge is rubber-lined.
In conclusion, understanding the design limitations of valves is critical in ensuring their safe and effective use in various industrial applications. These limitations, as outlined by Saudi Aramco’s standards, serve as guidelines to maintain the integrity and reliability of valves in demanding environments. Compliance with these standards is paramount to prevent failures and ensure the safety of operations.