Model test of the cutting properties of a shearer drum

According to similarity theory, we carried out a dimensional analysis of the shearer drum correlation parameters and built similarity criteria. Based on these, similarity models of shearer drums were developed. Simultaneously, based on an estab- lished cutting testbed of the coal and rock, cutting tests of different pick arrangements of the drum models were carried out, where the compressive strength of the analogous cutting material was 2.48 MPa and the drum rotary speed 67.5 r/min. The variance, the mean values, maxima and mean maxima of the torque load were analyzed for different type drum models. Moreover, the relation-ships between the type of pick arrangements and the cutting lump coal percentage were studied. The results indicate that the load fluctuation of the sequence drum is larger than that of the punnett square drum in the cutting process and the lump coal percentage and economic benefits of the sequence drum are inferior to the punnett square drum. We conclude that the punnett square drum is superior to the sequence drum.

Design and construction of HYSY981

This paper focuses on the independent design and construction of HYSY981. HYSY981,which China National Offshore Oil Corporation(CNOOC) possesses its intellectual property right,is brought forward by advanced research,concept design and combined basic design. The key technologies are the researches concerning global design,system integration,platform positioning,global performance analysis,structural strength and fatigue analysis,environment effect assessment of South China Sea,basin test and tunnel test,and construction technology of platform. Core technology of design and construction for the 6th deep water semi-submersible rig is held. Independent detail design and construction are also accomplished. These have improved technology of key equipment for China offshore oil exploitation.

Design of comprehensive test system for detecting overlying strata mining-induced fractures on surface with radon gas

Based on radon gas properties and its existing projects applications, we firstly attempted to apply geo- physical and chemical properties of radon gas in the field of mining engineering, and imported radioac- tive measurement method to detect the development process of the overlying strata mining-induced fractures and their contained water quality in underground coal mining, which not only innovates a more simple-fast-reliable detection method, but also further expands the applications of radon gas detection technology in mining field. A 3D simulation design of comprehensive testing system for detecting strata mining-induced fractures on surface with radon gas (CTSR) was carried out by using a large-scale 3D solid model design software Pro/Engineer (Pro/E), which overcame three main disadvantages of ''static design thought, 2D planar design and heavy workload for remodification design'' on exiting design for mining engineering test systems. Meanwhile, based on the simulation design results of Pro/E software, the sta- bility of the jack-screw pressure bar for the key component in CTSR was checked with a material mechan- ics theory, which provided a reliable basis for materials selection during the latter machining process.