IntroductionIn order to improve the control of volatile organic compounds (VOCs Control), RAYS has launched a full range of Fugitive Emission low-leakage Gate valves, Ball valves, Globe valves, and Butterfly valves that meet API 624 and API 641 standards, also can be ISO 15848, TA-LUFT, MESC SPEC 77-312.Fugitive Emission Low Leakage ValvesFugitive emissions are gas or vapor emissions from pressurized equipment that result from faulty equipment, leakage or other unforeseen events.The majority of these emissions come from industrial settings such as factories, power plants, oil refineries and chemical plants.Due to a large number of potential leak sources in these facilities and the difficulty in detecting and repairing them, these fugitive emissions can have significant consequences, including:Economic costs related to lost commodities.Environmental damage such as air pollution and the greenhouse effect.Long-term health risks to workers and local communities in close civic proximity of industrial facilities as a result of exposure to hazardous materials and volatile organic compounds (VOCs) such as benzene.Higher risk of fire and explosion in explosive environments where large amounts of flammable materials are contained under pressure.RAYS is focusing on two main standards that measure the emission levels of valves and packing products – API 641 and ISO 158481-1:2015 – and describing how RAYS valves are tested and certified to meet these standards, like Trunnion Ball Valve, Double Block and Bleed Ball Valve, Cryogenic Ball Valve, and Orbit Ball Valve, API 600 Gate Valve.API 641‘Type Testing of Quarter-Turn Valves for Fugitive Emissions’The API 641 standard is specifically relevant for quarter-turn valves. This standard applies to all stem seal materials, defines a stringent maximum allowable leakage of 100 parts per million by volume (ppmv), and utilizes methane as a testing medium and EPI Method 21 to measure emissions. It’s important to note that the U.S. Environmental Protection Agency (EPA) only recognizes API 641 emission testing.This standard calls for 610 mechanical cycles and 4 thermal cycles to evaluate the emission performance over an expected five-year lifespan of a valve. Under the Group A testing standard, the temperature is alternated between ambient temperatures and 260 C (500 F), and under the constant pressure of 600 psig. A static emissions measurement is taken before the cycling begins and this is followed by 14 static leakage measurements and seven dynamic leakage measurements during the testing procedure.The Quarter Turns Valves base on the stem with a quarter turn to open and close, such as DBB Ball Valve, DBB Plug Valve, Triple Offset Butterfly Valve, Cryogenic Ball Valve, and so on.ISO 15848-1:2015‘Industrial Valves – Measurement, Test and Qualification Procedures for Fugitive Emissions’Part 1 of the ISO 15841 standard outlines the testing and qualification procedures for the measuring of leakage from stem/shaft seals and body joints of isolation and control valves intended for application in environments containing volatile air pollutants or hazardous fluids.According to this standard, a valve must be cycled from 40% open to 60% open, and according to specific ratings for tightness class, endurance class, and temperature class:Tightness class – measured using either helium or methane as the test fluid, and defines standards for the maximum allowable leakage at each class rating.Endurance class ratings – the number of cycles that a valve has completed while successfully meeting at least the minimum tightness class for allowable leakage.Temperature class ratings – for different temperature ranges.The Industrial Valves include all kinds of valves, such as API 600 Gate Valve, BS 1873 Globe Valve, BS 1868 Check Valve, and API 594 Check Valve, and so on.And also include the quarter turns valves like Ball Valve and Butterfly ValveWhat RAYS can do?Through sophisticated processing equipment and testing instruments, RAYS strictly controls the surface roughness of the valve stem with a value of 0.4~0.8μm., and the surface roughness of the packing box with a value of 1.6~3.2μm. The selected graphite packing comes from suppliers and product models that have passed API 622 certification.Each valve is tested by a helium mass spectrometer in the laboratory of the RAYS factor. The external leakage of the valve is less than 100PPMv, and a special nameplate is hung before it can be allowed to leave the factory.RAYS can also design and customize products according to different fugitive emission standards such as ISO 15848, TA-LUFT, MESC SPEC 77-312 and other standards.We also welcome third-party inspection companies to the RAYS factory for acceptance. In order to provide protection for the user’s safe & reliable usage, the RAYS factory will issue a quality assurance certificate, a material certificate EN 10204.3.1, a fugitive emission test report, and a calibration certificate of the test instrument to the userProduct DescriptionName: Fugitive Emission low-leakage valveType: API 600 Gate Valve, API 6D Ball Valve, API 607 Ball Valve, Trunnion Ball Valve, Motorized Ball Valve, Triple Offset Butterfly Valve, Cryogenic Ball Valve, Extended Bonnet Ball Valve, Liquid Nitrogen Ball Valve, and etc.Specific Type: Double Block and bleed ball valve, Double Isolation and bleed ball valve, DBB ball valve, Rising Stem Ball Valve – Orbit Type DesignValve Standard: API 6D, API 608, API 607, API 6FA, ASME B16.34, GOST and EN / DIN.Material: Austenitic Stainless Steel, Forged Steel, and Cast Steel.ApplicationAll kinds of applications, specific in VOCs control. Also, The cryogenic ball valve is applicable.For any more information and inquiries, feel free to contact RAYS FLOW CONTROL.…

Since the modern industrial revolution, the global economy has developed by leaps and bounds. At the same time, mankind has paid a more painful environmental cost. With the increase of greenhouse gas emissions, extreme weather has become more and more common, and it seems to be the inescapable fate of mankind.The main culprit of environmental pollution and the greenhouse effect are industrial greenhouse gases and pollutants emitted into the atmosphere. In order to alleviate the environmental impact of global industrialization, strategies to control volatile gas emissions have been implemented internationally, and international standards or norms have been formed. While some developed countries have taken the lead in environmental control, we have also issued and implemented standards for FE valves, and are increasingly accepted by users. Every two years, “FUGITIVE EMISSIONS SUMMIT CHINA” takes place within the global industry while sharing their: experience, technology, and innovation on the topic of escape leakage control and LDAR practice. It is precisely because of the release of such relevant standards and the organization of activities that the standardization of fugitive emission has been more widely studied and developed.Fugitive emission refers to the emission of any chemical substance or compound in any physical form from an unanticipated or untrue leakage of equipment in an industrial site. The scientific dictionary defines fugitive emissions as Contaminants released into the atmosphere due to leakage, evaporation or wind, as well as several concepts related to them – such as low-evaporation of organic compounds. Typical chemical plant leak sources include valves (packing, bonnet connections), pump seals, compressors, flanges/joints, and safety/pressure relief devices.Valve leakage includes external leakage and internal leakage. The general leakage evaluation standard for valves is the visible leakage of the valve. However, fugitive emission strictly refers to invisible leakage, which needs to be detected by means of instruments, and often refers to leakage in packing area and gasket area. Gasket area is generally static seal and easy to control/diffuse leakage. Packing area is a dynamic seal and the movement of valve stem is easy to cause packing leakage.Generally speaking, the main factors affecting the valve packing leakage are as follows:TemperatureThe packing has a higher expansion value at a higher temperature than the metal member in contact therewith, and the packing is compressed. If the packing can pass the fugitive test at normal temperature, it can pass the fugitive test at high temperature (the loss rate of the filler itself is small), so the packing can easily pass through at the first normal temperature and the first high temperature. If the temperature is lowered from the first high temperature of 400 C to the second room temperature test, the shrinkage of the packing is larger than that of the metal part, but the cavity of the packing is unchanged compared with the first room temperature condition. Theoretically, the volume of the graphite packing is also unchanged. However, after high temperature, the packing has a certain loss of burning, so the inside of the packing will become loose. Then the resilience of the packing will decrease, and the stress inside the packing will be lowered after the high temperature drops to normal temperature. The torque of the pressure plate bolt is reduced, which is easy to cause leakage. However, by applying the packing to the torque value at the first room temperature, the original leak rate can be satisfied.Valve position toleranceThe shape and position tolerances of the parts that have an influence on the packing fugitive test are: the straightness of the valve stem, the machining position tolerance of the valve cover and the stem nut, and the assembly error. The accumulation of error eventually causes the valve stem to deflect at an angle to the packing. The side pressure of the packing rod in the reciprocating motion is constantly changing, and it is easy to cause leakage in a place where the side pressure is small. Also, after a certain number of reciprocating movements of the valve stem, the continuous extrusion of the packing causes the effective clearance of the inner hole of the packing to become larger, resulting in easier leakage.Stem, packing gland surface finishThe smoother the stem and packing gland, the easier the packing will seal. The tiny unevenness of the graphite-filled metal surface is much easier. From the economic analysis that satisfies the seal and valve manufacturing, the surface finish of the stem is generally Ra0.4-0.6 μm, and the surface finish of the packing gland is generally set to Ra1.6-3.2 μm.Gland, stem clearance, packing gland, and gland clearanceValve design and manufacturing should ensure that the gap between the gland and the valve stem is greater than the gap between the packing gland and the gland. This is to ensure that the valve stem will not bite with the gland during the movement. Although the gap between the gland and the valve stem is smaller, the packing is easier to seal, but the gap between the gland and the valve stem should not be too small. Due to the manufacturing error of the valve, too small of a gap is likely to cause a bite on the valve stem. Due to the presence of the packing end ring, maintaining a proper clearance between the gland and the stem does not cause the packing to leak beyond the standard.The environmental impact of the valve during use is an important indicator to evaluate the performance of the valve. Among them, the fugitive emission index of the valve is an important parameter to evaluate the environmental protection of the valve. The FE requirement of the valve has become the basic requirement for valve design and manufacture.In 2015, the API600 standard, widely used in the valve industry, first added the API 624 to the standard text for the valve’s FE test. With the Chinese National Standard (GB), the valve standard for hydro-treating units has also clearly required FE testing in accordance with ISO15848.ISO15848, VDI2440, API624, MESC SPE77/312, etc. are FE standards that are widely used in the valve field. These standards are based on helium or methane gas as a leak detection medium and are detected by proton spectroscopy. The sensitivity is usually 10-12 Pa*m3*s-1.Fugitive Emission is not a new topic. Although society’s concerns about air quality and environmental issues continue to heat up, the petrochemical industry’s application of FE control, leak detection, and repair technology have only just begun in recent years. Undoubtedly, the requirements for FE testing and evaluation have promoted the continuous improvement of industrial development. As far as the valve industry is concerned, the precision of machining and the quality of seals continue to improve. Thus, FE valves will gradually become the mainstream of the high-end valve market.…