subject: Why Valves And Gaskets Are Vital To The Processing Industry [print this page] Within many industries, there are a number of different process valves and gaskets that are out there. For the most part, many of the valves and gaskets that are out there depend on the type of industry they are used in. The types that will be discussed throughout this article are the pneumatic solenoid valves, shaft seals, and screw conveyor seals.
Pneumatic Solenoid Valves
This type of valve uses a solenoid in order to control the valve activation. These types of valves are used as a switch. They are responsible for routing the air to various types of pneumatic devices. In most cases, this involves an actuator of some type.
In general, the solenoid is composed of a core that is easy to move or balanced. Additionally, it channels the gas to the right port, while coupled to a smaller linear solenoid. Ultimately, the valve enables for the application of a small amount of current to the solonoid.
When this occurs, this cauuses the solenoid to change from a large amount of high pressure gas, which usually is around 100 psi. Depending on the solenoid, some of them have the capacity to operate at much higher pressures. They also vary on whether they have one, or two, or in some cases three output ports. The same applies with the requisite number of vents.
Commonly, these types of valves are used to control a linear actuator, or piston. A pneumatic solenoid works very similar to a transistor with the way that it works, since it has the ability to use a signal that is quite small in order to control a larger device. Additionally, it acts as the interface between pneumatic systems and electronic controllers.
Shaft Seals
Today, there are many types of shaft seals that are sold. The most common type consists of a rubberlike, elastic material ring that is bonded onto a metallic ring and pressed within the hole from which the shaft extents. This type of seal is used for the prevention of leaking fluids along the rotating shaft.
Anytime that a shaft extends past the housing enclosure with oil, then a seal is necessary. The way that the seal works is through the lip, which is pressed to fit around the shaft, in accordance to a helically wound garter spring. If the seal is properly constructed and installed, then the lip sits within a film of lubricant around 0.0001 inches thick. In the case that the film starts to get thick, the fluid starts to leak. On the other hand, if the film is too thin, then the lip will get too hot.
Screw Conveyor Seals
In most of the cases, electrical equipment is not provided for controlling the conveyors. Anytime equipment is selected for electrical control, the person must ensure they are using equipment that goes according to the national electrical safety code in addition to other national and local codes.
Generally, these kinds of seals contain such materials as slurries, pastes, and dry powders, which are effective for the use in screw conveyors in addition to other kinds of rotating equipment. In all cases, the installation of these types of parts should entail a thorough inspection for any type of damage it may have acquired throughout the time of shipment.
During this time, parts should be inspected for anything that is dented or bent. As for any type of minor damage, this can easily be repaired within the facility. Any type of assembly of the screw conveyor troughs should be straight. Therefore there should be no type of distortion with the assembly.
