# ISO 15761 Compliant Gate Valve Manufacturing Process

## Introduction to ISO 15761 Standard

The ISO 15761 standard specifies the requirements for steel gate valves designed for petroleum, petrochemical, and related industries. Compliance with this standard ensures that gate valves meet stringent quality, performance, and safety criteria for critical applications.

## Key Stages of the Manufacturing Process

### 1. Material Selection and Preparation

Manufacturers begin by selecting appropriate materials that meet ISO 15761 specifications:
– Carbon steel or alloy steel for valve bodies
– Stainless steel for trim components
– Compatible sealing materials

Materials undergo rigorous testing for chemical composition and mechanical properties before being approved for production.

### 2. Casting or Forging of Valve Components

The manufacturing process typically involves:
– Sand casting for complex body shapes
– Investment casting for precision components
– Forging for high-strength parts

Each casting or forging undergoes non-destructive testing (NDT) to detect any internal defects.

### 3. Machining Operations

Precision machining ensures dimensional accuracy:
– CNC turning for body and bonnet machining
– Milling for flange faces and sealing surfaces
– Drilling and tapping for bolt holes

Critical dimensions are verified against ISO 15761 requirements throughout the machining process.

### 4. Assembly and Testing

The assembly phase includes:
– Installation of stem, gate, and sealing components
– Torque verification of all fasteners
– Application of protective coatings

Each valve undergoes:
– Shell test (1.5 times design pressure)
– Seat test (1.1 times design pressure)
– Functional operation test

## Quality Control Measures

To ensure ISO 15761 compliance, manufacturers implement:
– Material traceability systems
– In-process inspections
– Final product verification
– Documentation of all test results

## Advantages of ISO 15761 Compliant Valves

– Consistent performance in demanding applications
– Interchangeability between manufacturers
– Reduced risk of field failures
– Compliance with international industry standards

The ISO 15761 compliant manufacturing process ensures gate valves meet the highest standards for reliability and safety in critical service applications. By following this rigorous process, manufacturers deliver products that perform consistently in the most challenging operating conditions.