Carly Wood Valves April 19th, 2019 - 12:33:53
So valved instruments are set up so that each valve, individually is in tune. Problems occur when performers must use valve combinations to adjust the pitch by more than three half steps. As you can see from the previous calculations, each time you add another half step, the working length must increase by more than the previous increase. Using the example of a 100" instrument, the third valve increases the length to 121.36" to produce an in-tune note three half steps below the original pitch. To lower the pitch a half step past this note, 8.09" of tubing is required. However, because the 2nd valve's length is only 6.67" this combination will be slightly sharp. This problem only compounds itself and in the 1-3 and 1-2-3 combinations, the deficit between the actual length and the "in-tune" length is 2.94" and 5.04" respectively. As you can tell, this creates a big problem, in fact, the 1-2-3 combination is about a fourth-step sharp!
A valve is a device which controls the flow rate, pressure or the direction. The controlled fluid can be the liquid, gas, the mixture of gas and liquid or the mixture of solid and liquid. The valve usually is composed of body, seat, bonnet, parts for opening or closing, actuating device, sealing element and so on. The controlling function of the valve depends on the actuating device or the movement of the fluid which drives the sliding, rotating or turning of the parts for opening or closing to change the area of the flow passage.
It is useful to say how counterfeit valves masquerading as the original. One of the techniques - misspelling the names of famous companies, such as, Bogati instead of Matca-Norca. Formally, this is not fake, because the original brand is not used. There are cases of writing only the names of countries, for example, USA, instead of adopting a made in Italy. The distortion of the famous logo, placing it, for example, not a diamond, but a square or a circle, also serves to confuse the buyer. Evidence of fraud may be the absence of any of the markings required for specific manufacturers. The sale of gas valves, and found such a primitive form of deception, as replacement faucet handles on native yellow - gas (gas valves are more expensive). Price savings may be too high, so choose the ball valves are safer from the range of recognized brands.
Butterfly valves are definitely useful. These seal the pipes, protecting them against impairment as well as being an energy saver. An instance would be on cold months, these lock in heat allowing liquid in the pipes to flow freely. These could also regulate the pressure level inside tubes and pipes. These also endure high levels of oil and corrosive properties of salt, a factor that makes these valuable aboard ships.
Now you're probably wondering how instrument makers know how much tubing to add so that the pitch is lowered by half step. And if you're not, I'm still going to explain it! Because of acoustical theory, to lower the pitch by a half step, the working length of the instrument must increase by about 1/15, or 6.67% of the working length. For explanation purposes I will be using an instrument which is 100 inches in length (which is actually close to length of a euphonium). This means the second valve should have a length of 100/15 or 6.67" in order to lower the pitch by one half step. Now, to lower it a half step past that you must add 106.67/15 or 7.11" so the first valve must have a length of 6.67"+7.11" or 13.77 inches. Now let me explain that last statement as it may have thrown some of you off. The reason the first valve would not be simply 2(6.67) is that in order to lower the pitch by a whole step, there must be enough tubing to lower the pitch by a half step (6.67") and then enough tubing to lower that pitch a half step (7.11"). This same theory goes for the third valve, and yields a length of 21.36 inches.
Swagelok Valves, as with all Swagelok products, are thoroughly tested, and the customer is assured that they will perform reliably, meet expectations of quality and are backed by the Swagelok Limited Lifetime guarantee. Valves are devices which are designed to open, close, or partially obstruct passageways in pipers, and in this way they regulate the flow of fluids and gasses. Valves have application over many different areas of many industries - this means they come in numerous designs and materials depending on the specifications they must meet. For this reason Swagelok produces top of the range Process, Instrumentation and Sanitary Valves, in a range of materials and end connections. Where necessary, Swagelok can manufacture or configure Valves to the special needs of a client's system requirements.