|
|
|
|
|
| What kind of blower should I consider - centrifugal or positive displacement? |
|
| Positive displacement and centrifugal blowers are found in wastewater treatment plants throughout the country. Both types have advantages and disadvantages, several of which are listed below: |
|
- PD blowers operate very efficiently because there is minimal slippage around the lobes. Whatever air goes in comes out. Centrifugal blowers are subject to more internal slippage around the rotor just like a centrifugal water pump, which makes them somewhat less efficient. Therefore, a larger motor may be required than with a PD blower to achieve the same performance.
- PD blowers are capable of high pressures up to 15 psi at both low and high flow rates. There are very few centrifugal blowers available that are designed to operate at flow rates below 400 CFM at pressures up to 8+ psi, while this performance can be achieved easily with various models of PD blowers. USABlueBook does offer several models of Siemens 2-stage blowers that cover much of this range.
- PD blowers are readily available in emergency situations. The M-D Competitor Plus, Roots URAI and Sutorbilt Legend series blowers, all of which are available from USABlueBook, are functional and dimensional drop-in replacements for one another.
- PD blowers can be noisier than centrifugals, even when equipped with silencers, because of gear noise and pulsating airflow. Most centrifugal blowers do not utilize a gear case and airflow is smooth, which translates to lower noise levels. This is a major reason for considering a centrifugal blower.
- PD blowers are generally belt driven. This is a plus in that blower speed can be varied to adjust blower output by changing the ratio of the V-belt sheaves. In addition, standard, off-the-shelf motors can be utilized. Centrifugal blowers with outputs less than 400 CFM are generally direct drive. Direct drive centrifugal blowers are very compact, quiet and competitively priced, especially in low-pressure (<4 psi) applications. However, direct drive centrifugal blowers have special motors that are often not economical to replace or service in the field. USABlueBook has two models of belt driven centrifugal blowers for applications up to 250 CFM at 9 psi.
|
|
|
Home | Site Map | About Us | Product Specials
Search Product | Quotes | Resource Center
Tech Help | Catalog Request | Contact Us
se habla español | World Service
Terms of Access | Sales Terms | My Account
All content © copyright 2008 Utility Supply of America, Inc.
|
