Mixing unit is widely used for trenchless machine and trenchless rigs, like for pipe injection, tunneling or micro tunneling, etc…
Depends on the kind and size of the trenchless machine and limitation of the job sites, various sizes of mixing tank and various capacity of mixing units are equipped to suit for the trenchless activities.
Centrifugal pump is widely used at drilling mud mixing unit. It can be used as water pump, mixing pump, or transfer pump. Mixing tank and transfer pump is the most popular used for drilling mud tank unit.
Some mixing tank unit use 1 centrifugal pump, while some drilling mud mixing unit are equipped with 2 centrifugal pumps. The 1 centrifugal pump mixing unit also have the function of mixing and transfer. The cost of 1 centrifugal pump unit is surely lower than 2 centrifugal pump units. Why there are some clients prefer 1 mixing pump unit, while some clients prefer 2 centrifugal pumps unit. What is the major difference of the 2 proposals?
In the 1 centrifugal pump unit, the mixing pump can be used as transfer pump as well. There will be a T-pipe equipped at the outlet of the mixing pump. In this case, the mixing pump is also transfer pump. But in this conditions, mixing and transfer function cannot be used at the same time. While the pump used for mixing, the transfer must be stopped. While the pump used for transfer, mixing must be stopped. The shift of transfer and mixing can be switched by operators, or controlled by level meters or sensors.
In the mixing tank unit with 2 centrifugal pumps, a pump used for mixing, another pump is used as transfer pump. There is a separate transfer pump in the system. Some clients prefer a separate transfer pump, although their cost will be higher compared with single pump mixing tank unit. But in this conditions, the clients can use the other tank as backup pump. The mixing unit can mix mud and transfer mud at the same time. There is level gauge for high level transfer and lower level mixing.