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Purpose The wax deposition in oil wells and pipelines is very viciously negative to the petroleum extraction and crude oil transportation, and it even causes severe blockage accident. This study aims to describe cleaning experiments performed on wax deposition of different deposition layer and experimental conditions to investigate the removal and tribological properties and chip formation. Design/methodology/approach An optical arrangement was used to visually record the cleaning process, whereas the friction forces were measured by a custom-built tribometer. Various measurements were performed with tool rake angles of 45° and −30° and cleaning depths from 1 to 5 mm. Findings Results from experiments and modeling suggest that the transition of chip was dependent on rake angle, wax performance and cleaning depth. While the cleaning depth increased, the friction and cleaning resistant force also increased. With the increase of cleaning depth, the wax layer cleaning quantity increased and the chip strengthened; hence, the curvature radius of chip was enhanced to form platy chip. The chip of wax–oil mixture was discontinuous units, and it was easy to adhere on the rake face with the increasing depth of cut. With an increase in cleaning depth, the friction and cleaning-resistant force also increased. Originality/value It is concluded that for effectively cleaning and stabilizing of pipeline cleaning machine, different cleaning parameters should be applied to accommodate wax layer or wax–oil mixture.

Under the background of the construction of new engineering and the strategy of “making China 2025”, the society has also put forward new requirements for the personnel training of mechanical specialties. Therefore, combining the training goal of mechanical design, manufacturing and automation in Beijing (Beijing), it is necessary to cultivate new direction and cultivate new growth point for “old” mechanical specialty. And social and economic development has a very important significance.

In order to improve the control performance of the nanopositioning and nanomeasuring machine (NPM) system, the microtribological behavior of thin fluorocarbon (FC) film under water lubrication was investigated by a microtribometer based on laser interferometers. Experimental results indicate that, on the transition from rigid to soft contact, the friction force under water lubrication firstly decreases and then increases. It is thought that the contact property plays a role in determining the microtribological properties. A simple physical explanation is provided based on the lubrication and mechanics theory. A systematic characterization of the frictional properties of the FC film is crucial for the further development of the NPM system.

Transient thin-film lubrication of the grease occurs in many machine elements including bearings, gears and cams. It also occurs in rolling-element bearings at the start or stop of motion. Thus the lubricant supply and film formation are important in ensuring the successful operation of a bearing.

Based on the characteristics of mobile target, a practical mobile target-identifying model of opposing forces has been put forward. According to the multilayered trait of target information, we will give a multisensor reasoning model of target identification and decision-making model.