Comparison of ASME B16.34 and API 600 Standards

# Comparison of ASME B16.34 and API 600 Standards

## Introduction

When it comes to industrial valves, two of the most widely recognized standards are ASME B16.34 and API 600. These standards provide critical specifications for the design, manufacturing, and testing of valves used in various industries. While they share some similarities, they also have distinct differences that engineers and procurement specialists should understand.

## Overview of ASME B16.34

Scope and Application

The ASME B16.34 standard covers pressure-temperature ratings, dimensions, materials, and testing requirements for valves made of steel, nickel-based alloys, and other alloys. It applies to flanged, threaded, and welding end valves.

Key Features

• Covers valves from NPS ½ to NPS 24
• Includes pressure classes from 150 to 4500
• Provides wall thickness requirements
• Specifies material requirements

## Overview of API 600

Scope and Application

API 600 specifically addresses bolted bonnet steel gate valves for petroleum and natural gas industries. It’s more specialized than ASME B16.34 and includes additional requirements for gate valves.

Key Features

• Focuses exclusively on steel gate valves
• Includes requirements for body/bonnet bolting
• Specifies stem design requirements
• Contains fire-safe design provisions

## Main Differences Between the Standards

1. Scope and Coverage

While ASME B16.34 covers all types of valves, API 600 is specifically for bolted bonnet steel gate valves. ASME B16.34 is more general, while API 600 is more specialized.

2. Pressure-Temperature Ratings

Both standards reference pressure-temperature ratings, but API 600 includes additional requirements for gate valve-specific applications in the oil and gas industry.

3. Testing Requirements

API 600 has more stringent testing requirements, particularly for fire-safe applications, which aren’t covered in ASME B16.34.

4. Material Specifications

API 600 includes specific material requirements for components like stems and wedges that go beyond what’s specified in ASME B16.34.

## When to Use Each Standard

ASME B16.34 Applications

This standard should be referenced when:

• Working with various valve types (not just gate valves)
• Needing general pressure-temperature ratings
• Requiring basic material specifications

API 600 Applications

This standard is more appropriate when:

• Specifically working with steel gate valves
• Operating in petroleum or natural gas industries
• Fire-safe requirements are necessary

## Conclusion

Both ASME B16.34 and API 600 serve important roles in valve specification and manufacturing. ASME B16.34 provides broad requirements applicable to many valve types, while API 600 offers specialized criteria for steel gate valves in demanding oil and gas applications. Understanding the differences between these standards helps ensure proper valve selection for specific industrial needs.