Dependence of static strength of large single crystals of synthetic diamond type and Ib octahedral habit after heat treatment on their size

This article focuses on the problem of using large single crystals of type Ib synthetic diamond in single crystal and drilling tools. According to the literature review for the use of large diamonds in drilling equipment relevant conditions. The is shown possible negative effects of the temperature load on the diamond single crystal. The is presented developed technique for estimating the static strength of large diamond single crystals. It has been shown that microcrystals in the form of octahedra and cubes are formed as a result of heat treatment on the surface of synthetic diamond single crystals. The results of studies of the strength of large single crystals of synthetic diamonds of millimeter size are shown. In contrast to the classical approach, when IIb crystals are used for the production of drilling equipment, we present Ib crystals because they are closer to natural diamond in terms of physical and mechanical properties. The static strength criterion was used to assess the strength. It has been shown that crystals with a size of 1000 ... 1100 μm have a higher value of static strength than crystals with a size of 1200 μm and larger.

Safety related study of Expanding Pin systems application in lifting and drilling equipment within Construction, Offshore, and Marine sectors

A questionnaire-based survey has been performed among original equipment manufacturers (OEMs), sub-suppliers, engineering companies, end-users, service & maintenance, and “others”, as part of an investigation to clarify their relationship to expanding pin system, compared to standard, cylindrical pins. In addition, a short literature study on onshore cranes is conducted. The survey is based on 9 questions about safety for personnel and machine, breakage, and wear of pins and supports, and installation and retrieval easiness of pins. The analysis of the responses indicates that safety for personnel and machines/equipment is regarded mainly as either “Important” or “Crucial and decisive”, and that the expanding pin solution is regarded as “better” or “equal” compared to the standard, cylindrical pin, both for “safety level”, “risk for breakage of pin & support”, “tear & wear on pin & support” and “installation and retrieval time”.

Phase Transformations and Microstructure of the Alloyed Steels for Mining Application

The dilatometer study of the austenite transformations in steels with different chemical composition was conducted. The studied steels were classified as the air hardened steels of different alloying systems (Cr-Ni-Mo, Cr-Mn-Si-Mo and Cr-Mo-V) designed for the mining applications (rock drilling equipment, drilling instrument). The microstructure of the steels was investigated after continuous cooling at the rates of 0.1...30 °C/s from the austenitization temperature down to the ambient temperature. The CCT diagrams of the studied steels were plotted showing that the alloying with different set of elements can provide the desired hardenability and microstructure.

Process Transferability of Friction Riveting of AA2024-T351/Polyetherimide (PEI) Joints Using Hand-Driven, Low-Cost Drilling Equipment

The present work deals with the transferability of Friction Riveting joining technology from laboratory equipment to adapted in-house, low-cost machinery. A G13 drilling machine was modified for the requirements of the selected joining technique, and joints were performed using polyethermide plates and AA2024 aluminum alloy rivets of 6 mm diameter. This diameter was not previously reported for Friction Riveting. The produced joints were mechanically tested under tensile loading (pullout tests) with ultimate tensile forces of 9500 ± 900 N. All tested specimens failed through full-rivet pullout, which is the weakest reported joint in Friction Riveting. In order to understand this behavior, FE models were created and analyzed. The models produced were in agreement with the experimental results, with failure initiated within the polymer under stress concentrations in the polymeric material above the deformed metallic anchor at an ultimate value of the stress of 878 MPa at the surface of the joint. Stresses decreased to less than half of the maximum value around the anchoring zone while the rivet was removed and towards the surface. The paper thus demonstrates the potential ease of applying and reproducing Friction Riveting with simple machinery, while contributing to an understanding of the mechanical behavior (initialization of failure) of joints.

DRILLING OF COMPLEXES WITH HYDRAULIC TRANSPORT OF A CORE FOR INCREASE OF EFFICIENCY OF GEOLOGICAL EXPLORATION WORKS

On the basis of an in-depth analysis of domestic achievements and the results of experimental and methodological works and practice the expediency of widespread use of improved technical means and technologies for drilling geological exploration wells with complexes counterflush coring (CCD) till the depth of 300 m upon sedimentary strata is substantiated. During the exploration of brown coal deposits and titanium placers, which convincingly confirm the high efficiency of CCD with appropriate modifi cations of equipment, technology and testing methods for specific productive horizons and host rocks. The best results of industrial application of CCD were obtained during the exploration of the Paromivske ilmenite placer deposit (2016). High technical and economic indicators of completion of work in difficult socio-economic and geological and technical conditions were achieved thanks to CCD application. The main argument in favor of CCD is undoubtedly proven by ultra-high productivity with a significant reduction in cost and improved quality of the work. The operational geological informational content of the method allows timely adjustments and responsibly choose the most optimal flexible schemes and methods of geological research. Due to the significantly reduced timing of drilling operations, field research can be carried out shorter at the most favorable climatic conditions and seasons of agricultural activity. The mobile circulation system excludes the construction of earthen sedimentation tanks, which signifi cantly reduces the size of disturbed soils, their contamination and prevents the loss of flushing fluid. The peculiarities of the technology and organization of work promote close cooperation, mutual control and understanding of technical, geological, geophysical and other personnel serving and actively mobilize for high-quality and highly efficient performance of geological tasks. A reduction of heavy operations in the technological process significantly improves the working conditions for the service personnel, increases the production culture, and contributes to the attractiveness of the drilling profession. Ukraine has sufficient production facilities (at Kiev Drilling Equipment Plant, Dnepropetrovsk Drilling Equipment Plant, Discovery - Drilling Equipment. Ukraine LLC, etc.), which are capable of providing geological exploration companies with modern CCD. The main reasons that hinder the development of modern highly efficient geological exploration technologies are recognized and the optimal ways to solve the problem of widespread introduction of CCD are featured.

Microstructure and Mechanical Properties of High Strength Low Alloy Steel Q550D

Drilling equipment is the key of oil and gas drilling development. Its manufacturing quality and service performance have important influence on oil and gas drilling development safety. The application of high strength grade steel plays an important role in improving drilling equipment manufacturing level and service performance. In this paper, the chemical composition, microstructure, tensile properties, impact properties and hardness of TMCP Q550D and Q-T Q550D high-strength low-alloy steel were tested and compared, and the application feasibility for drilling equipment manufacture was analyzed comprehensively. The experimental results show that the mechanical properties of Q550D by two different methods were obviously higher than the requirement of national standard. Q550D steel had excellent plasticity and toughness, which meets the requirement of drilling equipment manufacture. The main difference between different steel lied in their chemical composition and micro-structure. Carbon content of TMCP Q550D steel plate was lower than that of QT Q550D, and TMCP Q550 was mainly depend on TMCP technology and micro-alloy elements, whose micro-structure was mainly granular bainite. Q-T Q550D was mainly depend on Q-T technology, and its microstructure was tempered sorbite with obvious banded structure and slightly low toughness.

Microstructure and Properties of Q690D High Strength Low Alloy Steel

As one of the core equipment components of oil and gas drilling rig, derrick is also the main heavy-duty component. Working environment of derrick is quite bad, the material for which should have not only high strength, but also good plasticity, toughness and weldability. In this paper, the chemical composition, microstructure, tensile properties, impact properties and hardness of three typical Q690D high strength low alloy steel manufactured from different methods were studied. The application feasibility of Q690 for drilling derrick manufacture was analyzed. The experimental results show that the carbon equivalent, tensile properties and impact absorption energy of Q690D steel with different thickness obtained by TMCP and Q-T process were obviously higher than the requirement of corresponding standard. TMCP Q690D steel had better toughness, lower carbon content and carbon equivalent, and its micro-structure was granular bainite. Carbon content of Q-T Q690D steel plate was relatively higher than that of TMCP Q690D, and the toughness was slightly lower than that of TMCP Q690D. The microstructure Q-T Q690D was tempered sorbite, and there was certain zonal segregation in center part. The thickness of steel plate used in derrick was usually less than 40 mm, whose manufacturing technology of Q690D was mature. There is broad application prospect in the field of drilling equipment. The application of Q690D for drilling equipment not only improve the strength grade of equipment materials, but also help to optimize the design of components and ensure service safety.