DREDGING SYSTEMS AND THE BASIC DREDGE LAWS©
Each dredge law provides you with a fundamental and convenient relationship between two or more of the factors which affect dredge production. By the judicious application of these laws, you will be able to understand the complex dredging cycle and to make the changes in design or operating procedure to maximize the output of a given dredge.
| Abbreviations USED |
| ~ |
= |
Varies as |
| Vs |
= |
Velocity in suction pipe |
| ds |
= |
Diameter of suction pipe |
| As |
= |
Area of suction pipe |
| hv |
= |
Velocity head |
| hE |
= |
Entrance loss |
| hf |
= |
Friction loss |
| hsg |
= |
Head requirement for specific gravity over 1.0 |
| H |
= |
Total dynamic head |
| D.D. |
= |
Digging depth |
| S.G. or sg |
= |
Specific gravity |
| hb |
= |
Barometric head |
| g |
= |
Acceleration due to gravity |
| hs |
= |
Suction head |
|
| |
1 - PRODUCTION VARIES AS FLOW X AVERAGE % SOLIDS.
2 - AVG. % SOLIDS = PEAK % SOLIDS X DREDGE EFFICIENCY.
3 - PEAK % SOLIDS VARIES AS VS; TYPE OF SOLIDS:
4 - MAXIMUM (SHORT LINE) PRODUCTION VARIES AS AREA OF SUCTION PIPE
5 - OPTIMUM VS VARIES AS DIGGING DEPTH
6 - DISCHARGE LINE LENGTH VARIES AS PUMP HP
7 - PRODUCTION IS LIMITED BY
(1) Suction Conditions (Barometric Head)
(2) Pump HP Available (Discharge Head Requirement
(3) Velocity (Conveying Capacity) |
