# Comparison of ASME B16.34 and API 600 Standards

## Introduction

In the world of industrial valves, two standards stand out as critical references for design, manufacturing, and testing: ASME B16.34 and API 600. While both standards address valve requirements, they serve different purposes and have distinct scopes. This article explores the key differences and similarities between these two important standards.

## Scope and Purpose

ASME B16.34

The ASME B16.34 standard provides requirements for the design, materials, dimensions, testing, and inspection of valves with flanged, threaded, and welding end connections. It covers pressure-temperature ratings, dimensions, tolerances, and marking for various types of valves.

API 600

API 600 is specifically focused on bolted bonnet steel gate valves for petroleum and natural gas industries. It provides more detailed requirements for gate valve design, materials, face-to-face dimensions, pressure testing, and inspection than ASME B16.34.

## Key Differences

Valve Types Covered

ASME B16.34 applies to a broader range of valve types including gate, globe, check, ball, plug, and butterfly valves. API 600 is exclusively for bolted bonnet steel gate valves.

Industry Focus

While ASME B16.34 serves general industrial applications, API 600 is specifically tailored for the oil and gas industry with additional requirements for harsh service conditions.

Testing Requirements

API 600 includes more stringent testing requirements than ASME B16.34, particularly for high-pressure applications in the petroleum industry.

## Similarities

Pressure-Temperature Ratings

Both standards reference similar pressure-temperature ratings for materials, though API 600 may have additional requirements for specific service conditions.

Material Specifications

The two standards share many common material specifications, particularly for carbon and alloy steels commonly used in valve construction.

Quality Requirements

Both standards emphasize the importance of quality control in manufacturing processes and require documentation of material traceability.

## When to Use Each Standard

ASME B16.34 should be specified when you need a general valve standard applicable to multiple valve types across various industries. API 600 should be used when specifically requiring bolted bonnet steel gate valves for petroleum or natural gas applications where additional robustness is needed.

Many projects actually reference both standards simultaneously, using ASME B16.34 for general requirements and API 600 for specific gate valve requirements in oil and gas applications.

## Conclusion

Understanding the differences between ASME B16.34 and API 600 is crucial for proper valve specification. While ASME B16.34 provides broader coverage of valve types, API 600 offers more specialized requirements for gate valves in demanding oil and gas applications. Engineers should carefully consider their specific application requirements when choosing between or combining these standards.