Generally speaking, a plug valve and a ball valve may absolve the same function (fluid shut-off). The main differences are:   Plug valves are more economical than ball valves, generally, due to their simpler design   Plug valves are less prone to contamination by debris, and accumulation of dirt in the interstitial spaces, compared to ball valves (an issue that is frequently faced by ball valves, due to the spaces existing between the sphere and the body of the valve)   Ball valves require more maintenance than plug valves, especially after planned or unplanned plant shut-downs   Plug valves have a full port design, without pressure drops, ball valves may be reduced or full port (a full port ball valve would be heavier and bulkier than a plug valve of the same size)   In general, plug valves are good alternatives to ball valves, even if ball valves are still considered industry standard for shut-off operations at least in the oil & gas industry.

This year the holiday for family reunions, Mid-Autumn Festival, and for the country's founding, National Day, coincide.   As the two special festivals both fall on October 1 this year, Chinese cities, certainly including Xiamen where Dervos lays its root in, are festooned with flowers and lanterns and holding colorful activities to celebrate the joyful occasion.     And here in Xiamen, we have a traditional activity called Bo Bing, or "gambling for cakes", to celebrate the Mid-Autumn Festival. The game requires six dice and a wide mouthed bowl. Players throw the dice in turn and wins a specific prize depending on the dice combination. We divided into three groups. Screams and cheers rose up and fell down as every time dice being tossed. Because the quantity of gifts is limited, whoever tosses the specific number earlier, gets more presents till all are given out.   After the exciting game, we headed towards a beautiful and cozy coastal hotel for the rest of this happy time. In there, the games, the songs and the palatable food all added together to make a memorable occasion.  At the stretching beach and on the pleasant moment, we flew balloons that carry our best wishes and sang our company song --“we are a loving family”. Happiness and group cohesion drew a perfect period of this wonderful night.

The V-ball valves or V-port ball valves are similar to traditional ball in which there is a V-notch on a ball-shaped disc to control flow by a rotating quarter-turn motion. The “V-port" is a particular design that bring about precise flow and the ability to regulate and control flow by V balls of  different degrees. These special valves are used in a wide range of chemical applications, including the most challenging services with many advantages.   Flow Modulating The accuracy of V-ball valves provides equal percentage flow characteristics. As the ball rotates, desired flow rates can be achieved by positioning the ball anywhere between 0° and 90°.   Bubble tight shutoff V-ball valves have the ability to close tightly. Therefore, no other shutoff valves is required when using a V-ball valve on a globe valve.   Lower pressure drop V-ball valves also have a higher coefficient of flow (Cv) than the same size globe valve, which directs the flow and uses a plug to control the flow through the valve. This means that the flow rate achieved by one shut-off valve can be achieved with a smaller V-ball size.   Higher shutoff pressure. A 90°rotation of the ball allows the V-ball to close at a higher operating pressure. This therefore allows the use of lower torque actuators, resulting in cost savings and increased efficiency for the end user.

There are quite a few types of changeover valves, and according to different standards, there are different subdivisions. But in general, it is mainly four kinds, for motorized changeover valve, manual changeover valve, solenoid valve and electro-hydraulic changeover valve.   1. What is a changeover valve?   Changeover valve, from a professional point of view, is a kind of direction-change valve. It is mainly used to achieve the flow of hydraulic oil, cut off the machine changeover operations, pressure relieving, as well as sequential action control, so its use is very wide.   2. The working principle of reversing valve   The changeover valve uses a  driving mechanism outside the valve to rotate the drive shaft, and then activates the valve plate, etc. So that the fluid can flow into the outlet of the lower part of the valve, and can be changed from time to time to achieve the purpose of periodically changing the flow direction.   3. Changeover valve classification  (1) Motorized changeover valve, it is also known as a stroke valve.    (2) Electromagnetic changeover valve, electromagnetic changeover valve is the use of electromagnetic attraction to manipulate the spool changeover control valve.    (3) Electro-hydraulic changeover valve, electro-hydraulic changeover valve is a composite valve composed of solenoid valve and hydraulic changeover valve.    (4) Manual changeover valve, manual changeover valve is a changeover control valve with a manual lever to manipulate the spool shift direction-changing valve.  

Among the anti-corrosion materials, PTFE has incomparable excellent performance. In addition to outstanding chemical stability, it also has satisfactory anti-fouling and anti-stickiness, small dynamic and static friction coefficient, good anti-wear performance. Using it as a valve opening and closing the sealing material, the friction between the sealing surface and required operating torque will be reduced, hence product life increases. the application scope can also be extended to the food, pharmaceutical industry and so on. Fluorine lined valves, also known as anti-corrosion valves, are usually found in harsh working conditions. The media is either toxic and harmful chemicals, or pretty corrosive acids and bases or organic solvents. That means improper use and operation will elicit significant economic losses and serious consequences. Applicable media: various concentrations of acid and alkali salt and certain organic solvents. Fluorine is extolled as the world's most ideal anti-corrosion materials, has been widely used in the rotational molding of large equipment and piping lining. Correct use and maintenance of the valve can extend the service life of fluorine lined valves, then what can be done to effectively protect it? 1. Carefully read the instruction manual before use. 2. Use it within the range of pressure, temperature and media given by the nameplate or instruction. 3. To prevent fluorine lined valves from excessive piping stresses due to temperature changes, temperature changes should be minimized and U-shaped expansion joints should be added before and after the valve. 4. For some unstable and easily decomposed media (such media will expand after decomposition,  resulting in an abnormal pressure rise) and media that can cause valve damage or leakage, measures should be taken to eliminate or limit the factors that cause the decomposition of unstable media. 5. For fluorine lined valves in pipelines of toxic, flammable, explosive, highly corrosive media, it is strictly prohibited to replace the packing under pressure. Even the valves are designed with sealing part, it is not recommended to replace the packing under pressure either. 6. For pipelines with self-combustible media, measures should be taken to ensure that the ambient and working temperatures do not exceed the self-combustibility point of the media to avoid the danger from sunlight or external fires.

Dervos recently attained two new kinds of technical patent that refer to a kind of gate valve and a kind of globe valve with filtration ability. Most of the gate valves open and close by turning the handwheel connected to the stem, which causes the stem to move up and down in the guide groove and press the valve plate to the seat. However, the stem and the valve body press each other firmly, and if the gate valve is not used for a long time, it will take huge efforts to turn the wheel to open and close the valve, which impedes the valve use. Dervos new patent helps to alleviate the difficulty by inserting the valve plate into the groove of the valve body, the lifting assembly can quickly raise the valve plate so that the inlet and outlet can be connected and open the gate valve. On the other hand, the assembly can lower the valve plate to the lower surface of the valve plate and contact the bottom of the groove of the valve plate, so that the inlet and outlet cannot be connected and the gate valve can be closed. As for the globe valve, it is known as one of the most widely used valves to stop the flow of medium in a pipeline. The current piping system often fails to work properly due to impurities in the fluid in the pipeline, so it is necessary to add filtration function to the globe valve. By optimizing the internal structure, Dervos has innovatively installed strainers and other fittings inside the valve body, so that the globe valve has these advantages: 1. No need to cut off the medium when cleaning the strainer. 2. Easy replacement of filters. 3. Outstanding sealing performance. Dervos has been committed to bringing quality products to the market, and we also keep gonging on a creative development path.