# Comparison of ASME B16.34 and API 600 Standards

## Introduction

When it comes to industrial valves, two commonly referenced standards are ASME B16.34 and API 600. While both standards address valve design and manufacturing, they serve different purposes and have distinct requirements. Understanding the differences between these standards is crucial for engineers, procurement specialists, and quality control professionals working in the oil and gas, power generation, and process industries.

## Scope and Application

### ASME B16.34

ASME B16.34 is a comprehensive standard that covers the design, materials, dimensions, testing, and inspection requirements for valves with flanged, threaded, and welding end connections. It applies to a wide range of valve types including gate, globe, check, ball, and butterfly valves.

### API 600

API 600 specifically focuses on bolted bonnet steel gate valves for petroleum and natural gas industries. It’s more specialized than ASME B16.34 and includes additional requirements for materials, design, and testing that are particularly relevant to the oil and gas sector.

## Key Differences

### 1. Valve Types Covered

ASME B16.34 has a broader scope, applying to multiple valve types across various industries. API 600, on the other hand, is exclusively for steel gate valves used in petroleum applications.

### 2. Pressure-Temperature Ratings

Both standards provide pressure-temperature ratings, but API 600 includes more stringent requirements for the petroleum industry’s demanding conditions. ASME B16.34 offers more general guidelines applicable to a wider range of services.

### 3. Material Requirements

ASME B16.34 Materials

The standard references ASME material specifications and allows a broader range of materials suitable for various applications.

API 600 Materials

This standard specifies materials that are specifically suitable for petroleum service, with additional requirements for corrosion resistance and mechanical properties.

### 4. Testing Requirements

While both standards require pressure testing, API 600 includes more rigorous testing protocols including extended shell tests and additional seat leakage tests that are critical for oil and gas applications.

### 5. Design Features

API 600 mandates certain design features like backseat functionality and stem design that are specifically important for gate valves in petroleum service. ASME B16.34 provides more general design guidelines applicable to various valve types.

## When to Use Each Standard

The choice between ASME B16.34 and API 600 depends on the application:

• Use ASME B16.34 for general industrial valves across various industries
• Use API 600 specifically for steel gate valves in petroleum and natural gas service
• Many projects require compliance with both standards for gate valves in oil and gas applications

## Conclusion

While ASME B16.34 and API 600 both address valve manufacturing, they serve different purposes. ASME B16.34 provides broad requirements for various valve types, while API 600 offers specialized specifications for gate valves in the petroleum industry. Understanding these differences helps ensure proper valve selection and compliance with project requirements.