PD Blower (Positive Displacement Blower)

A PD blower also known as positive displacement blower, or rotary air blower, is a type of blower that is used to move gas or air for a variety of applications. To be precise, these devices utilize positive displacement technology by trapping a certain volume of air then discharging or forcing it out against the system pressure. This air is usually forced into some type of pipe or hose to propel materials or gas to a destination.

If we dissect a PD blower we will notice that the main parts of the machine are two rotors that are joined together by gears surrounded by a blower casing. Most of the blowers also come with a sound absorber, air screen and other parts to improve efficiency, but when explaining how the apparatus functions we only need to focus on the rotors, blower casing, inlet side and outlet side of the machine. PD Blowers are used in a variety of applications and industries to improve processes and cut lead times and hence making them a desired investment tool.

Low frequency noise tends to dominate when blower pitch line velocity is below the blower’s critical speed, and a reactive blower silencer is probably the right choice in that condition. In case the blower’s PLV is above its critical speed, then a reactive­ absorptive silencer should be used due to the presence of high mid­ to­ upper band noise, as well as low frequency pulses.

Positive Displacement blowers are prone to destructive low frequency pulse generated noise. Often, they can also have high mid­ to­ upper band noise levels. In many cases this means that blower silencers are necessary on both the open air inlets and pressurized discharges of PD blowers.

Everest Blowers is a leading manufacturer, distributor and service provider for positive displacement blowers, vacuum pumps, and related equipment.