Options Available for DBS Drive Units
By Nils R. Young, PE, Managing Director
DBS Manufacturing is able to provide a number of useful options for your clarifier or thickener drive. If there is an option you need that is not included in this article, or not included in our product line found at www.www.dbsmfg.com, DBS will be glad to propose a design if it is feasible. Our engineering staff strives to keep up with the state-of-the-art developments in machine design and improvement. We are always monitoring the advances in machine design and control, utilizing the latest materials in innovative ways to solve clarifier and thickener drive needs.
DBS is familiar with many types and styles of electric motors. We offer motors from all of the major manufacturers and will be glad to provide any electric motor you wish to use. We can provide space heaters, thermistors, oversized conduit boxes, explosion proof protection, terminal blocks, special nameplates, topicalization and weatherproofing.
Metric components are available as an option on any drive unit. We offer electric motors in IEC frames with IP55 and IP65 protection. Metric couplings, fittings and piping are available for all primary speed reducers. Speed reducers are available from well-established gearbox manufacturers in Europe or Japan.
We offer traditional electromechanical primary reducers and were the first to introduce the use of hydraulics. The hydraulic primary reducer offers the ability to provide simple directional control for rake rotation. A manual or solenoid operated valve is available to provide this feature. All F-type and H-type primary reducers are available with directional control as an option. State-of-the-art variable frequency drives are offered as the modern approach to speed control. We also offer mechanical variable speed options, but strongly recommend using the modern approach. The VFD provides reversibility, overload protection and soft-start capability. DBS offers 4-20mA torque signal sensing on all our drive units. Our torque gauge mechanism is very accurate and customers have frequently used the 4-20mA signal to monitor sludge blanket depth.
At a large water treatment plant for a major metropolitan city in the Midwest, the customer raised concerns about condensate accumulation of up to one pint per day. In response, DBS developed our condensate control system (CCU). It is a simple retrofittable device that, in this customer's case, reduced the condensate accumulation to a negligible level. Our condensate control unit had the capability of being retrofitted to any existing DBS clarifier or thickener drive. The CCU has been discontinued because a new low maintenance option has been introduced. See Advantages of the Low Maintenance Drive (LMD) Vs. Condensate Control Unit (CCU) for more information.
We have recently developed a filler breather system for all the open ports on our drive unit that is for use in extremely dirty atmospheres. The system offers three-micron filtration with water absorption capability. This was developed in response to the environments found in the recaust circuit in paper mills, but is applicable to any "extreme" environment.
Loss of motion indication is sometimes required. DBS offers lost motion switches on any of our drive units. We take two approaches: We will provide a proximity switch, specified by the customer, which will provide a signal that can be processed by the customer's DCS system. We can also provide a switch closure that indicates loss of motion without requiring the customer to process the signal.
We can provide oil heaters in any of the main gear housings on our drive units. An oil heater may allow a customer to operate the drive unit through winter and summer seasons without changing the lubricant or using expensive synthetic oils. DBS offers oil level switches and oil temperature switches. Normally, these are used in hydraulic reservoirs, but they can also be fitted to the main gear housing.
Most DBS drive units are available with lift options. A lift mechanism allows the rakes to be raised, allowing the drive unit to operate under higher loading conditions. The lift mechanism offered on the Pier Mounted drive unit is totally self-contained in the drive unit itself, eliminating telescoping center columns.
DBS is familiar with many other forms of instrumentation and will be glad to offer proposals for any additional instrumentation that the customer may require. Please visit our web site at www.dbsmfg.com for more information on these options and DBS drive units. You may also contact us via e-mail at [email protected].