Model DB - Double Orifice Plate
Double orifice plate regulators are available with capacities from 30 l/s up to 10,000 l/s – see diagram. They are designed for submerged installation and may be used for all types of discharge water, i.e. storm water, sewage water or mixed storm and sewage water. The special feature of the DB flow regulator is that it is capable of controlling large volumes at low heads. It is ideal in situations when the required discharge volume is so large in relation to the head that a vortex chamber brake cannot be used owing to the required size.
The DB flow regulator has infinitely adjustable orifice plates, which may be adjusted to ±25% of the capacity in mean position. The capacity may be changed on site without replacing any components; just loosen four screws with a hexagon socket head wrench and adjust the orifice plate. For a change of capacity, please contact Mosbaek A/S. We identify the regulator by means of its reference number and calculate the setting of the orifice plate to suit the new capacity.
Owing to the patented orifice plate system the DB flow regulator is the only of its kind on the market.
The flow regulator is available in a variety of dimensions and is specially designed to suit the specific application, so that it will always be possible to obtain optimum characteristics within the range of application.
In general, the DB regulators ensure that the flow, Q, is almost constantly equal to the nominal capacity, Qdim, over a large interval of upstream heads. The capacity, Qdim, may be obtained at the top of the ”bump” of the characteristics as well as in the design point. This is illustrated on the characteristic curve of the DB flow regulator.
The inlet orifice plate is inclined following to the flow direction, which makes the water move onwards in the pipe system until the water level is on a level with the sides of the flow regulator when the outlet orifice plate starts operating.
The outlet orifice plate is inclined against the flow direction, which results in a strong contraction of the outlet water jet, and consequently, a considerable increase of the braking effect. Thus a larger orifice opening is obtained.
Low construction, operation and maintenance costs
DB flow regulators are designed for embedment. As the cast banquettes are sloping from all sides towards the bottom race, the build-up of deposits is reduced to a minimum because the water is directed to the regulator. Also, it is easy to clean the structure by flushing it from the top before descending. Thus, inspection, service of change of capacity may be carried out under the most hygienic conditions.
The DB flow regulator takes up very little space and may therefore often be installed in existing or planned wells or tanks.
Other features of the DB regulators are:
- Straight flow
- Mired flow with 20‰ downgrade
- Constantly large orifice opening
- No moving parts
- No electrical components
- Made of stainless, acid-proof steel AISI 316L (Werkstoff 1.4404)
In the aggregate these features contribute to low plant construction, operating and maintenance costs.
Generally the DB flow regulator is used in connection with:
- Outlet from detention basins
- Overflow structures
- Pipe storage
- Capacity limits in hydraulic nodal points
- Inlets to pumping stations
- Inlets to separators and waste water treatment plants