BRUKS Rockwood has supplied a fixed, shuttling, and slewing shiploader to the Port of Portland in Portland, Oregon.The system is being supplied by Kinder Morgan Company, a terminal operator in bulk material products. Designed to handle soda ash material, this system loads at 2,450tph (metric tonnes per hour) while using a telescopic chute which is positioned by shuttling and slewing of the shiploader.

The shiploader is designed as a fixed unit mounted on the wharf. A four-legged structural tower steel truss assembly supports the shiploading boom conveyor and loading spout. The loader’s boom will run in a horizontal plane and extend outward to provide accommodation to the loading point on the ship. There is a conveyor that extends out with the boom, so the material will discharge while the boom is being extended/contracted. This process is called shuttling. The shuttling boom has two sets of counter weights. One is a static weight that mounts to the truss structure. The second is a dynamic weight that moves as the truss moves in and out, that acts as an additional balance for the assembly. Along with the shuttling process comes the slewing process.

Slewing is the process of means to turn circularly without change of place. The slew bearing assembly is a high capacity ball bearing mounted to the top of the base of the truss right below of the loading boom. Slewing permits the booms to rotate a certain amount of degrees, for this specific loader it approximately moves 200° of rotation. These multiple processes are used to accommodate Handysize vessels on up to Panamax vessels ships. To assist with material control and efficient loading, the boom is equipped with a telescopic spout created by Cleveland Cascades.

The Cleveland Cascade chute is designed to cascade material using interlocking steel funnels to close in the bottom of the chute while sealing in material and dust. The chute is controlled by an electric motor; gear reducer and two lift pulleys. Sheaves mounted at the four corners of the upper support provide for even lifting and stability. The chute can discharge up to 2,500tph while having a volumetric rate of 2,400 cubic metres/hours.

After the ship has been properly positioned at the dock, the operator can position the loading conveyor over the appropriate hold by shuttling and slewing the boom into the operating zone, and lowering the telescopic spout into the hold. The shuttling and boom slewing features will enable the operator to position the loading spout in multiple areas within the hold area. The operator performs these functions using a portable radio controller.

Once the ship is filled to maximum or preferred load the operator moves out of the holding cavity by reversing the previous controls, and the ship heads on its way to its destination. In all, the Port of Portland shiploader is a perfect example of maximizing the efficiency of material handling.