Asco: A Pioneer In Solenoid Valve Technology
Asco solenoid valves are among the best established lines of valves on the market, and serve as crucial components in a great many industries. Essentially, a solenoid is nothing more than a spool or spiral of engine wire. This inductive coil produces an electromagnetic field whenever a current is passed through it. When activated, depending on the polarization of the coil, that field will exert a horizontal pulling or pushing force on anything within the coil. Typically, a coil will have an armature (a slug or cylindrical piece of metal) which is drawn into or expelled from the coil when the solenoid is activated. The force of the solenoid’s coil is balanced by a spring which, either stretched or compressed by the armature during activation, returns the armature to its initial position when the solenoid is deactivated.
Via this inline motion, the armature can in turn be used to perform a variety of functions, such as ringing a doorbell, or, in more outlandish modern cases, serving as the jumping mechanism for a toy robot. Most commonly, though, solenoids are used to control the flow of gases or fluids through valves. In the case of Asco solenoid valves, the solenoid’s armature itself is the pin that prevents fluids or gases from flowing through the valve. Once activated, the solenoid coil pulls the pin into itself, allowing gas or fluid to flow directly through the device. Asco solenoid valves are reliable enough to be used in large factories to control the movement of bulk fluids, such as milk, as well in small, handheld devices such as paintball guns, where they are responsible for controlling the pressurised gas that propels ammunition through the barrel.
Solenoids are also responsible for a common part of most peoples’ everyday lives. Anytime you successfully start your car, you’ve activated an inline solenoid. When you turn the key in the ignition of your car, the starter solenoid of your engine receives a supply of electric current, coming partly from the ignition switch but predominantly from your car’s battery. The armature of the starter solenoid then pushes together a pair of heavy contacts, relaying the current it receives to the starter motor.
If you’re looking to get hold of valves for building or repairing any sort of product, there are a few companies that top the list in terms of the reputation of their products. First is unquestionably the company I’ve already mentioned, Asco. There are lines of Asco solenoid valves capable of controlling the flow of air, water, gas, steam and oil. The company’s products range from the most simple, bipositional on-and-off valves to complete flow control solutions. Asco was actually the first company to develop and manufacture solenoid valves (way back in 1910) and continued its domination of the market throughout the 20th century, expanding into new product fields by manufacturing air operated valves, micro-miniature solenoid valves, pneumatic controls, sensors and position indication technology. With nearly a century’s worth of refinement, its products are about as streamlined and perfect as you’re likely to find.
Another award-winning company in this department is MAC valves, which has been in operation since the late 1940’s. The company that came from the creators of the (now patented) oval armature, MAC manufactures 3-Way, 4-Way and In-Line valves in all manner of sizes. The company is also one of the top suppliers of proportional air-controlled valves. Alternatively, if you’re looking for a good custom manufacturer of in-line solenoid valves, FESTO is probably the best company to call.
Due to their polarisation, solenoid coils will only pull or push – no solenoid can do both. Thus AC power is unnecessary, though there are of course coils that are designed to be used with AC current – such coils have a ‘shading coil’, which delays the collapse of the magnetic field of the solenoid due to current-crossing, thus ‘averaging out’ the magnetic field so that it acts as if it were DC-powered.. One does need to keep in mind, however, that using DC power on an AC coil will probably result in the coil burning up, while using AC power on a DC coil may result in the coil not developing the full force required to adequately shift the armature (due to the limitations place on it by inductance).
