Produced chemicals such as H2S, CO2, condensates, other hydrocarbon solvents, along with crude oil , natural gas and injected media (frac acid and gas compositions) can all have a major impact on the condition of the valve cavity lubricant. This can result in the lubricant being dissolved and displaced from the valve cavity, rendering the initial valve components dry, exposed to wear and damage from increased friction. A cavity devoid of lubricant will also permit the ingress and entrapment of contaminants in the valve cavity, such as corrosive fluids or sand.
This can cause severe valve operational problems, including damage to the component sealing surfaces, an increase in the required actuation torque or force, or worst case in seizure of the valve. Implementing a preventative maintenance program that includes a routine valve re-lubrication will ensure optimum valve protection.
A fundamental requirement of the valve lubricant is the resistance to liquid and gas phase hydrocarbons. To test a lubricant, a sample of the lubricant is applied to a glass plate, and then placed within a container of hydrocarbon fluid. The fluid breaks down the GP Valve Grease very quickly. In the valve, the grease will be washed out of the cavity when cycled just a few times. The lubricant should not be unaffected by the hydrocarbon fluid, regardless of exposure time, thus providing long term cavity retention.
March 2011 Referenced by http://www.rsclare.com/oil_gas.html
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Magnatrol now offers its popular stainless steel 2-way Solenoid valve in a 3-inch size. Valves are full port, and are said to require no differential pressure to open and are easily serviced while in the pipeline.
Applications include de-ionized water, ammonias, vegetable oil, fuel oil, gas, steam, solvents, cryogenics and oxygen. The valves are of a packless construction with continuous duty coils for all AC and DC voltages, available normally open or normally closed with 150- and 300-pound flanged connections.
Omega's SV-1200 miniature solenoid valves are suitable for applications in analysis technology, reliably handling difficult liquids such as acids, bases, pharmaceutical elements, and fluids in biotechnology processes.
Thermal isolation of the actuator and fluid ensures accurate measurements for metering applications. A perfluorelastomer separation diaphragm hermetically isolates the fluid medium from the actuator. Other features include universal functions, small size, and simple and fast electrical connection to reduce installation costs. An LED also provides safe and convenient monitoring.
Process Control Solenoid Valves For Water, Oil, Air, Gas, Steam, Cryogenics, Vacuum, Solvents, Brine, Oxygen, Corrosive Fluids
Every valve is manufactured and tested in-house following Quality Assurance Standards where production operations are under the control of our dedicated, experienced staff and workforce.
Many conveying lines consist of a single vertical upward line followed by a single horizontal line. If the horizontal line has an appreciable length, a velocity equal to or higher than the saltation velocity is required to maintain dilute-phase flow in the line. A significant reduction in the velocity required to maintain dilute-phase flow can be achieved if the horizontal line is angled downward as in Figure 1. A downward angle of only 15 degrees is enough to significantly reduce the velocity required to prevent solids salting out in the line.
Because it is more difficult to maintain solids in a dilute-phase mode in a horizontal line than in a vertical line, the saltation velocity is greater than the choking velocity. The ratio of the saltation velocity to the choking velocity ranges from approximately 3 to 6. This means that the minimum system velocity in a system composed of horizontal and vertical conveying lines in the saltation velocity. Many people try to decrease the diameter of the horizontal lines to simultaneously increase the gas velocity and to minimize the volumetric gas requirements of the system. However, decreasing the diameter of the horizontal lines also increases the solids mass flux in the lines, which means that the saltation velocity increases as well which generally results in no net gain by decreasing the line diameter.
Many solid pneumatic conveying applications have a requirement that the solids have to be conveyed in the dilute phase mode. In many of these applications, the conveying system consists of both vertical and horizontal pneumatic lines. The minimum velocity required to maintain solids in the dilute-phase mode in a vertical conveying line is called the choking velocity (Uch). The minimum velocity required to maintain solids in the dilute-phase mode in a horizontal conveying line is called the saltation velocity (Usalt).
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Ningbo Lida Pneumatic Complete Sets Co.,Ltd. specializing pneumatic components,solenoid valve,air cylinder & pneumatic fittings that these are inexpensive . It has with more than 15years.