GB/T 19672 is a Chinese standard that adopts and modifies ISO 14313:1999 "Oil and Gas Industry – Pipeline Transportation System – Pipeline Valve" and API 6D:2002 "Pipeline Valve." This standard outlines the technical specifications for gate valves, ball valves, check valves, and plug valves used in natural gas and oil pipelines. It covers terms, structural types, parameters, ordering requirements, technical specifications, materials, inspection rules, testing methods, and marking. The standard applies to pipeline valves with nominal pressure ranging from PN16 to PN420 and nominal sizes from DN15 to DN1200.
Compared to ISO 14313 and API 6D, GB/T 19672 has several key differences. First, it follows the formatting guidelines of GB/T 1.1-2000, which differs from the international standards. Second, some terminology and definitions are adapted to align with domestic practices. Third, it introduces additional nominal pressures such as PN16, PN25, and PN40. Fourth, the ordering requirements have been modified. Fifth, it increases the structural length for ball valves larger than DN1000. Sixth, it adds specific bolt thread requirements for valve housing connections. Seventh, it incorporates welding and inspection requirements based on Chinese regulations. Lastly, it includes detailed inspection rules for valves.
The main technical content of GB/T 19672 includes definitions of terms like full-bore valves, reduced-bore valves, and one-way or two-way valves to ensure accurate application. It describes typical structures and connection types for gate, ball, plug, and check valves used in long-distance pipelines. The pressure-temperature rating and valve body material comply with GB 9131, ensuring compatibility with existing industry standards.
The structural length of valves is aligned with API 6D specifications, facilitating interchangeability between different manufacturers. For valves with one end welded and the other flanged, specific structural length requirements are defined. The standard also specifies the representation of flow paths, including nominal size and actual bore diameter, helping users distinguish between full-bore, reduced-bore, and shrink valves.
To meet cleaning and maintenance needs for long-distance pipelines, the minimum bore size and cross-sectional shape of the valve channels are regulated. Structural requirements for long-distance pipeline valves include performance and operational criteria, such as operating torque and functional performance. The standard also lists common valve body materials, corrosion protection measures, hardness requirements, and welding procedures.
Testing procedures are based on API 6D, covering all necessary inspection items, test conditions, duration, and methods. The standard was developed by the National Valve Standardization Technical Committee (SAC/TC188) and came into effect on August 1, 2005. It serves as a critical reference for the design, manufacture, and use of pipeline valves in China's oil and gas industry.
Picosecond Laser
Picosecond pulsed diode Laser features with integrated electronics, narrow pulse duration, high repetition frequency and easy operation. It is widely used in fluorescence excitation, time resolve spectrum, high sensitive absorption spectroscopy, etc.
Picosecond laser has uperior beam quality, best reliability, mode-locked & picosecond Pulsed Laser, pulsed duration could be less than 20 ps. Housed in compact packages, are the perfect choice for design in and integration into OEM instrumentation and systems and also for end user applications in research and development.
Specifications
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Model
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Output power
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Rep. rate (MHz)
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Pulse duration (ps)
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MDL-PS-450
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10 μW~ 0.5mW
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0.1~80
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100-1000
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MDL-PS-640
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50 μW~3.5 mW
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0.1~80
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100-1000
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MDL-PS-655
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20 μW~1.5 mW
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100kHz~200MHz
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100-1000
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MDL-PS-785
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70 μW~4.2 mW
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0.1~80
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100-1000
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MDL-PS-808
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90 μW~6.0 mW
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0.1~80
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100-1000
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MDL-PS-852
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10 μW~1.0 mW
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0.1~80
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100-1000
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MDL-PS-940
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20 μW~1.5 mW
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100kHz~200MHz
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100-1000
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MDL-PS-980
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20 μW~1.5 mW
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0.1-80
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100-1000
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Dimensions
Laser
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Optional Power Supply (100-240VAC)
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190(L)×100(W) ×58(H) mm3, 1.2kg
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121 (L) ×50(W) ×31 (H) mm3, 0.3kg
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High Power Picosecond Laser,Picosecond Laser,Picosecond Laser Pen,Picosecond Laser Diode
Changchun New Industries Optoelectronics Technology Co., Ltd. , https://www.cnioptics.com