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March 15, 2024 by Brina
The differentiation between API 600 and API 602 standards is pivotal when it comes to manufacturing industrial valves.
While both are crucial benchmarks, they address distinct aspects.
API 600 primarily delves into valve design, while API 602 focuses on evaluating valves for low emissions.
Read on to learn more about their distinction, which is essential for you to make an informed decision.
Table of Contents
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- What Is API 602?
- What Is API 600?
- API 602 Vs. API 600
- Design Differences
- Rated Temperature Variations
- Sealing Components Distinctions
- Type Tests for Packing Sets to Measure Valve Performance
- Leakage Tests
- Endurance Tests
- Temperature and Pressure Cycling
- Torque Tests
- Material Compatibility Tests
- Key Takeaway
What Is API 602?
API 602 is the standard specification for Gate, Globe, and check valves with sizes DN 100 [NPS 4] or Smaller in the Petroleum and Natural Gas Industries. These valves are intended to withstand extreme pressure or temperature conditions.
API 602 is the standard for 4” and smaller forged steel gate valves used in industrial facilities. This specification outlines the design and construction criteria for these valves, as well as information on extended-body forged valves.
The specification is available in ISO format, providing comprehensive coverage of all design and material criteria for small forged valves. It includes important dimensions like stem diameter minimums, wall thickness, and stuffing box size.
API 602 is a compact and robust valve designed for high-pressure and high-temperature services, made of stainless, carbon, and alloy steel. This product finds applications in natural gas and petroleum industries alike with its standard sealing surface that’s wear-proof. Plus, its polished stem seal area ensures optimal air tightness with no leakage of fugitive emissions. SIO is an established supplier of API 602 valves throughout North America and Europe, with all types and sizes from 150 to 2500mm available.
What Is API 600?
API 600 is an American standard that specifies design criteria for cast steel (carbon and alloy) gate valves used in petroleum industry applications. It specifies key dimensions like stem diameter minimums, wall thickness, and stuffing box size.
The two major types of API 600 valves are rising and non-rising types. When opened, the rising stem type rises above the handwheel, so it’s easier for operators to tell whether the valve is open or closed.
A rising stem makes it easy for the valve operator to make sure their handle is not touching the operating nut, as any interference between them can lead to leakage or prevent operation.
The two primary materials that can be utilized are ductile iron and stainless steel. Both materials come in various sizes and variations.
API 600 gate valve trims come in two varieties: a separate seat ring design or integrated into the body of the valve. Either way, they must be made out of the same material as the body to meet specifications.
API 602 Vs. API 600
The primary distinction between API 602 and API 600 is that the former applies to valve types, while the latter tests for the low emissions capability of a valve. Testing for each type is different based on design, rated temperature, and sealing components.
Essentially, these tests are conducted to demonstrate the low emission capability of a valve over an extended lifecycle. Also referred to as type tests, they offer an invaluable way to verify the performance of various packing sets.
API 602 addresses small forged gate valves, such as ANSI B16 class 150, 300, 600 & 800 valves as well as some other types. It provides design criteria and material designations for these valves along with important dimension information like stem diameter minimums, stuffing box size, wall thickness, and weight.
These valves are ideal for use in a variety of applications, from pipelines to industrial facilities, with less stringent throttling and shut-off requirements than refineries. They come in various sizes and grades with either a cast or forged body.
In addition to these valves, the API 600 standard also specifies heavy-duty ball, check, and plug valves used primarily in pipelines. This standard outlines their design, construction, and testing requirements.
Design Differences
API 602 and API 600 standards primarily differ in their focus.
API 602 is concerned with specifying valve types and addressing aspects of design tailored to different applications.
On the other hand, API 600 concentrates on testing the low emissions capability of valves, assessing their environmental impact and efficiency in emission control.
Rated Temperature Variations
Another notable difference lies in the rated temperature considerations.
API 602 and API 600 standards account for distinct temperature specifications.
These variations are crucial as they ensure that valves are designed and tested to perform optimally within specific temperature ranges, meeting the requirements of diverse industrial environments.
Sealing Components Distinctions
The standards diverge in their evaluation of sealing components.
API 602 and API 600 outline specific criteria for assessing the effectiveness and durability of sealing mechanisms within valves.
These distinctions in sealing components play a pivotal role in determining the reliability and efficiency of valves across different applications and operating conditions.
Type Tests for Packing Sets to Measure Valve Performance
Type tests, synonymous with performance tests, represent a critical phase in validating the effectiveness of diverse packing sets used in valves.
These tests serve as an invaluable means of scrutinizing the performance characteristics and durability of packing components.
The objective is to assess how well the packing sets withstand operational conditions and fulfill their intended functions within the valve.
Leakage Tests
Type tests often include leakage assessments to gauge the sealing capabilities of packing sets.
By subjecting the valve to different pressure and temperature conditions, engineers can verify if the packing effectively prevents leaks, ensuring the integrity of the valve’s performance.
Endurance Tests
Endurance or longevity tests are conducted to simulate prolonged operational cycles.
This helps in evaluating the durability of packing materials and their ability to withstand wear and tear over an extended period, ensuring the longevity of the valve.
Temperature and Pressure Cycling
Type tests involve subjecting the packing sets to varying temperature and pressure conditions. This simulates the fluctuations the valve may encounter during normal operations.
Testing under different environmental conditions helps validate the packing’s resilience and adaptability.
Torque Tests
Torque tests assess the force required to actuate the valve with the installed packing.
These tests ensure that the packing does not impede the smooth operation of the valve and can handle the necessary torque without compromising performance.
Material Compatibility Tests
Evaluating the compatibility of packing materials with the substances they will encounter is crucial.
Type tests may include assessments of how the packing reacts to specific fluids, ensuring it remains effective without degrading or corroding over time.
Type tests play a pivotal role in the quality assurance process, providing manufacturers and users with confidence in the reliability and functionality of packing sets within valves.
Key Takeaway
The key distinction between API 600 and API 602 lies in their focus: API 600 standards address valve design and specifications, while API 602 pertains to low emissions testing.
Notably, API 602 emphasizes verifying a valve’s capability to maintain low emissions.
Understanding these standards is crucial for ensuring compliance with industry benchmarks and facilitating the selection of valves suitable for specific applications.
Xintai Valves provides an expansive selection of valves for various applications. Their products can be found in residential and commercial buildings, water supply systems, wastewater treatment plants, and chemical plants to direct flow, shut off access to water sources, prevent backflow, and adjust system pressure.