Four micro-holes were made using micro-EDM on the rake face of the cemented carbide (WC/TiC/Co) tools. CaF2solid lubricants were embedded into the microholes to form self-lubricating tool (SLT-1). Dry machining tests on hardened steel were carried out with the SLT-1 self-lubricating tool and conventional tool (SLT-2). The cutting forces, tool wear and friction coefficient were measured and compared. It was shown that the cutting performance of SLT-1 self-lubricating tool was greatly improved compared with that of the SLT-2 conventional tool. Through the analysis of cutting force theory and test results, the mechanism of cutting performance improvement was considered to be the formation of a self-lubricating film on the rake face which decreases the shear stress and the reduction of contact length between chip and tool.

A method is presented for determining the pouring point location of concrete pump truck. The method does not change the structure of the concrete pump truck, only need to replace the hydraulic cylinders of booms with the hydraulic cylinders with displacement senor, and the displacement sensors are mounted in the inside of the hydraulic cylinders and do not need any extra protection. The relationship formulas between the contraction and expansion amounts of the hydraulic cylinders and the pouring point location are derived and programmed to input into a data processing unit. The contraction and expansion amounts of the hydraulic cylinders are timely acquired and inputted into the data processing unit, then the pouring point location can be displayed in real-time on the screen of radio controller, and the workers can quickly and accurately locate the pouring point of the concrete pump truck to poured point.

On the basis of study of traditional selection method about locking point, this paper made a large number of trial and comparative analysis for the selection of locking point, got a more effective method and gave the application example.