Patent ID: 7407022

Claim:
A method of moving drill cuttings, the method comprising placing drill cuttings in a hopper, said hopper including a swing tube member communicating between a discharge port and alternately with first and second pumping cylinders, the method comprising alternately reciprocating respective piston heads within said first and second cylinders in synchronization with movement and positioning of said swing tube member to repeatedly: (i) draw drill cuttings into said first cylinder while at the same time forcing drill cuttings from said second cylinder through said swing tube member to said discharge port, (ii) pause while said swing tube member is transitioned from alignment with an outlet from said second cylinder to alignment with an outlet from said first cylinder, (iii) subsequently draw drill cuttings into said second cylinder while at the same time forcing drill cuttings from said first cylinder through said swing tube member to said discharge port and (iv) pause while said swing tube member is transitioned from alignment with the outlet of said first cylinder to alignment with the outlet of said second cylinder, the method further comprising creating a pressure of at least 50 bar (735 psi) within the swing tube member during operations (i) and (iii), said pressure within said swing tube member dropping by at least 80% during operations (ii) and (iv).