Here we have an ideal situation where Boreline is absolutely, the ideal solution. This open-pit mine has issues with internal scaling, corrosion, regular pump failures and is in a remote location.
When calculating the cost a well, the Life Costs need to be kept in mind. These include all the costs associated with operating the well.
In this case, the pumps are removed every 4 months, as there is a considerable internal build-up of calcium carbonate. Externally, the steel pipe below water level is corroding within a couple of years. Site and water conditions are aggressive and with these wells forming part of a larger dewatering system designed to keep the pit dry, safe and stable, we cannot take any chances.
In the following pictures, we will first see the removal of the rigid column followed by the reinstallation of the pump on Boreline Flexible Drop Pipe.
Rigid column pipe removed 20ft at a time
The rigid column pipe is available in 20ft (6m) sections. This is removed in sections using a crane, wrenches, cheaters, and numerous crew who go “running” around the well.
Rigid pipe being removed laid on the side
As each length is removed, it will be laid on the side away from the well. In this way it is not obstructing the removal of the other sections.
Unscrewing rigid column pipe
No, the man at the back is not holding a whip! He is simply making sure no one gets caught in the power cable that is laid on the side as each section is removed. Note the removed sections in the back-ground.
This pump is set at 600ft (180m) so this little “Well Jig” is going to take place 30 times!! (During this time, I did see the guys trip numerous times, cables got tangled, the wrench slipped and often fell but thankfully, no one got hurt)
It did however take the better part of 5 hours to have the pump out.
As the pipe is removed the internal build-up, which was a layer almost ¼” (6mm) thick was brown and dried to white. This build-up has already reduced the diameter of the pipe by ½” within 6 months!
The Engineers keep a close eye on proceedings
Power Cable Straps
The Boreline is laid on the ground away from the well. The Cable Straps are inserted into the Boreline rib and the power cable is supported along the entire length.
Pump, cable and clamp attached
The pump and power cable have been attached. The Boreline lifting clamp grips the Boreline and we are ready to install.
All 600ft of Boreline will be installed in one continuous length.
Clamp is attached and pump and Boreline raised
The Boreline clamp simply squeezes the Boreline. This can then be lifted and lowered into the well. The clamp will rest on the well casing while a second clamp is attached further along the Boreline. The second clamp is then raised, lifting the first clamp off the well casing. This first clamp is removed and the entire length lowered until the second clamp comes to rest on the casing. In this manner, the pump and Boreline are lowered down simply, safely and efficiently. There are no joints, no welding, no twisting and no turning.