Grade 7 Grade 9 Titanium Weld Neck Flanges ASME B16.5 Class 150 Titanium Flange Raised Face Titanium for Industrial Systems

Abstract

Titanium, with its unique combination of strength, light weight, and exceptional corrosion resistance, is a material of choice for demanding applications in industrial systems. This paper explores the characteristics, manufacturing standards, and applications of Grade 7 and Grade 9 titanium weld neck flanges in accordance with ASME B16.5 Class 150 specifications. Special focus is placed on the raised face design of titanium flanges, highlighting their advantages in industrial systems, including chemical processing, aerospace, oil and gas, and power generation. We examine the benefits and challenges associated with these titanium alloys and their usage in high-performance applications.

Introduction

Flanges are vital components in connecting pipe systems, valves, pumps, and other equipment in various industrial settings. Among the materials used for flanges, titanium stands out for its superior properties, particularly its high strength-to-weight ratio, corrosion resistance, and ability to withstand high temperatures and pressures. Grade 7 and Grade 9 titanium alloys are commonly used in manufacturing titanium weld neck flanges, particularly for industrial systems that demand reliability and durability in harsh environments.

Grade 7 titanium, also known as Ti-0.15Pd, contains small amounts of palladium to improve corrosion resistance, making it ideal for applications in chemical processing and marine environments. Grade 9 titanium, or Ti-3Al-2.5V, is an alloy that includes aluminum and vanadium, which enhances its strength while retaining excellent corrosion resistance.

Titanium Alloys: Grade 7 and Grade 9

1. Grade 7 Titanium (Ti-0.15Pd): This alloy is primarily used in applications that require enhanced resistance to corrosion, particularly in reducing environments. The addition of palladium (Pd) gives Grade 7 titanium exceptional resistance to acids and other aggressive chemicals, making it suitable for chemical processing, petrochemical industries, and seawater environments. The alloy maintains high strength and good weldability, making it effective for manufacturing welded components, such as titanium weld neck flanges.

2. Grade 9 Titanium (Ti-3Al-2.5V): Titanium Grade 9, also known as Ti-3Al-2.5V, is a higher-strength alloy containing 3% aluminum and 2.5% vanadium. This composition provides a significant improvement in strength while retaining excellent corrosion resistance. It is often used in applications that require high strength-to-weight ratios and resistance to corrosive environments. Its strength makes it a suitable material for components such as weld neck flanges, particularly in industries like aerospace, automotive, and oil and gas.

Titanium Weld Neck Flanges

Weld neck flanges are a popular flange design in industrial systems, particularly for high-pressure applications. They are characterized by a long neck that provides a smooth transition between the flange and the pipe. The neck enhances the strength and integrity of the connection by reducing stress concentration, which is crucial in high-pressure or high-stress environments.

Titanium weld neck flanges are typically manufactured using Grade 7 and Grade 9 titanium alloys due to their superior strength, corrosion resistance, and performance under extreme conditions. These alloys are particularly effective in environments such as chemical processing plants, offshore oil rigs, and aerospace applications, where materials are exposed to harsh conditions like high pressures, extreme temperatures, and corrosive chemicals.

ASME B16.5 Class 150 Specifications

ASME B16.5 is a standard that covers the design, material, dimensions, and testing requirements for pipe flanges and flanged fittings. The Class 150 designation specifies the pressure rating for flanges, indicating that these flanges can withstand a maximum pressure of 150 pounds per square inch (psi). This standard ensures that titanium weld neck flanges are manufactured to precise specifications, with rigorous testing to ensure their reliability and safety under the specified pressure conditions.

The Class 150 rating is commonly used in medium-pressure applications, including water systems, gas systems, and chemical processes. Titanium flanges manufactured to this standard are particularly advantageous for industries where corrosion resistance and high strength are essential, such as the chemical, pharmaceutical, and power generation sectors.

Raised Face Design

Titanium weld neck flanges are often manufactured with a raised face (RF) design, which is the most common flange face type in industrial applications. The raised face provides a contact surface that is slightly elevated above the flange’s bolting circle, allowing for better sealing and resistance to leakage under pressure.

The raised face design is particularly beneficial in high-pressure applications because it increases the pressure rating of the flange connection, ensuring a more secure seal between the flange and the mating part. This design is ideal for industrial systems that operate in environments where leakage could lead to significant safety hazards or operational failures. The raised face also helps to distribute the load more evenly across the seal, reducing the likelihood of gasket failure.

Applications of Titanium Weld Neck Flanges

1. Chemical Processing: Titanium flanges, especially Grade 7 and Grade 9, are widely used in chemical plants due to their resistance to corrosive chemicals and high temperatures. They are used to connect pipes and vessels that transport hazardous materials, ensuring the integrity of the system under challenging conditions.

2. Aerospace: Titanium alloys are ideal for aerospace applications due to their high strength-to-weight ratio. Titanium weld neck flanges are used in aircraft engine systems, airframes, and other critical components where reliability and performance are paramount.

3. Oil and Gas: Titanium flanges are crucial in the oil and gas industry, particularly in offshore drilling operations. Titanium’s resistance to saltwater corrosion and its ability to withstand high pressures make it the material of choice for flanges in subsea pipelines, oil rigs, and refineries.

4. Power Generation: In power plants, titanium flanges are used in steam systems, heat exchangers, and turbines. Their ability to perform under high temperatures and pressures, coupled with excellent corrosion resistance, makes them ideal for maintaining the integrity of power generation systems.

Conclusion

Titanium weld neck flanges made from Grade 7 and Grade 9 titanium alloys, manufactured in accordance with ASME B16.5 Class 150 standards, offer exceptional performance for industrial systems. Their combination of high strength, light weight, and outstanding corrosion resistance makes them indispensable in industries such as chemical processing, aerospace, oil and gas, and power generation. The raised face design ensures a reliable and secure connection, even under high-pressure conditions, contributing to the long-term durability and safety of industrial systems. As industrial applications continue to demand materials capable of withstanding extreme environments, titanium weld neck flanges will play an increasingly critical role in ensuring system integrity and operational efficiency.

Grade 7 Grade 9 Titanium Weld Neck Flanges ASME B16.5 Class 150 Titanium Flange Raised Face Titanium for Industrial Systems

Titanium Flanges Standard Specification

ASTM B381 Titanium Flanges

Ti Forged and Plate Flange

Test Certificates for Titanium Pipe Flanges:

Manufacturer's Test Certificate (TC) according to EN 10204/3.1B:

• This certificate indicates that the titanium pipe flanges have been tested and verified in accordance with EN 10204/3.1B. The 3.1B certification means that the material has been tested by the manufacturer and the test results are based on the manufacturer's own inspection and testing, which is provided to the buyer.

Raw Materials Certificate:

• This document confirms that the raw materials used for manufacturing the titanium pipe flanges meet the necessary chemical and mechanical properties as per the applicable standards, ensuring material traceability.

100% Radiography Test Report:

• This report confirms that the titanium pipe flanges have been subjected to 100% radiography (X-ray inspection) to detect any internal defects, such as cracks, voids, or inclusions. It ensures the structural integrity and quality of the flange.

Third Party Inspection Report:

• This report is issued by an independent third-party inspection agency. It verifies that the flanges have been tested and meet the required specifications and standards. Third-party inspections add an additional layer of reliability and trust for the buyer.

EN 10204 3.1 Certificate:

• The EN 10204 3.1 certificate provides verification that the product meets the technical specifications and the required mechanical properties. It ensures that the products conform to the relevant European standards and regulations.

Additional Requirement: NACE MR 01075:

• NACE MR 01075 is a standard published by the National Association of Corrosion Engineers, which defines requirements for materials used in sour service environments. If requested, this certificate ensures that the titanium pipe flanges are suitable for use in environments with hydrogen sulfide (H2S), where corrosion resistance is critical.

Ferrite Content Certificate (if requested):

• Some applications may require a specific ferrite content to ensure the material's suitability for certain welding processes or environments. This certificate ensures the ferrite content complies with the required standards.

Applications of Titanium Flanges include:

Aerospace: Titanium flanges are widely used in the aerospace industry, particularly in engines, airframes, and other critical systems due to their lightweight, strength, and corrosion resistance.
Chemical Processing: In chemical plants, titanium flanges are used to connect reactors, heat exchangers, and piping systems, as they can withstand high temperatures and aggressive corrosive environments.
Power Generation: Titanium flanges are used in nuclear reactors, thermal power plants, gas turbines, and other equipment due to their excellent high-temperature resistance and durability.
Oil and Gas: In offshore drilling, refineries, and pipeline systems, titanium flanges are ideal due to their resistance to saltwater corrosion and high-temperature endurance.
Medical Applications: Titanium flanges are used in biomedical fields, such as implants, prosthetics, and surgical devices, due to their biocompatibility and resistance to body fluid corrosion.


Common Standards and Specifications for Titanium Flanges include:

• Standards: ASTM B381, ASME SB381
• Sizes: 1/2” to 18”
• Pressure Ratings: 150#, 300#, 600#, 900#, 1500#, 2500#, PN6, PN10, PN16, PN25, PN40, PN64
• Flange Face Types: Flat Face (FF), Raised Face (RF), Ring Type Joint (RTJ)
• Material Grades:
  • Grade 1 Titanium (CP Ti)
  • Grade 2 Titanium (CP Ti)
  • Grade 4 Titanium (Ti-0.25Pd)
  • Grade 5 Titanium (Ti-6Al-4V)
  • Grade 7 Titanium (Ti-0.15Pd)

These material grades provide a range of options based on strength, corrosion resistance, and heat resistance, catering to the diverse needs of various industries. Titanium flanges, due to their excellent performance under extreme conditions, have become essential components in many fields. Whether in high-pressure systems, medical implants, or offshore oil drilling, titanium flanges meet the most demanding performance requirements.