# ISO 15761 Standard Manufacturing Process for Gate Valves

## Introduction to ISO 15761 Standard

The ISO 15761 standard specifies requirements for the design, manufacturing, and testing of steel gate valves for petroleum, petrochemical, and related industries. This international standard ensures that gate valves meet strict quality and performance criteria, providing reliability in critical applications.

## Key Stages of the Manufacturing Process

### 1. Material Selection and Preparation

Manufacturers must select materials that comply with ISO 15761 requirements, typically including carbon steel, stainless steel, or alloy steel. The standard specifies:

– Chemical composition limits
– Mechanical properties
– Heat treatment requirements

### 2. Casting or Forging Process

The valve body manufacturing begins with either:

Casting method: Molten metal is poured into molds to form the basic valve shape

Forging method: Metal is shaped under high pressure while in a solid state

Both methods must meet ISO 15761 dimensional and quality standards.

### 3. Machining Operations

Precision machining ensures proper fit and function:

– CNC turning for accurate dimensions
– Milling for flat surfaces and complex shapes
– Drilling and tapping for bolt holes
– Grinding for sealing surfaces

### 4. Assembly Process

The assembly stage includes:

1. Installing the gate and stem
2. Mounting seats and seals
3. Applying proper lubrication
4. Torquing bolts to specified values

### 5. Testing and Quality Control

ISO 15761 mandates rigorous testing:

Pressure Testing

Each valve undergoes hydrostatic tests at 1.5 times the maximum working pressure

Leak Testing

Both shell and seat leakage tests are performed according to standard requirements

Functional Testing

Operational tests verify smooth opening/closing and proper sealing

## Benefits of ISO 15761 Compliance

Manufacturing gate valves according to ISO 15761 offers several advantages:

– Ensured product quality and reliability
– International recognition and acceptance
– Improved safety in critical applications
– Standardized dimensions for interchangeability
– Traceability of materials and processes

## Conclusion

The ISO 15761 standard provides a comprehensive framework for manufacturing high-quality gate valves. By following this standardized process, manufacturers can produce reliable products that meet the demanding requirements of the petroleum and petrochemical industries while ensuring safety and performance consistency across global markets.