The pig is forced down the pipeline by hydrostatic or pneumatic pressure that is applied behind the pig. |
This model has four speed fully automatic transmission and hydrostatic drive steering. |
The servos are attached to the control shaft of the hydrostatic pump on each wheel. |
In operation, hydrostatic head pressure forces stormwater flow into the housing where primary separation of insoluble contaminants occurs. |
This is best achieved by a constant hydrostatic pressure exerted by the fluid itself. |
This can happen through leverage by rigid levers, or it can occur in pliant hydrostatic cylinders of constant volume. |