Contact of working surfaces for spherical washers and recommendations for determining the gap in the joint

In article analyzes the technical requirements for spherical washers used in threaded connections of pumps, which made it possible to highlight contradictions in paragraphs of the current standards for pump fasteners. They regarding recommendations for manufacturing technology and control of the working surfaces of washers. Publication analysis in the spherical surfaces lapping showed the absence of research in the spherical surfaces contact after lapping and the dependence of contact parameters by the technological parameters for this operation. The presence of a gap in conjunction with spherical washers after the lapping process was proved geometrically. Its location was determined, and a mathematical dependence was obtained to determine the maximum gap value in conjunction. It was found that the gap depends on the design parameters of the washers' conjunction and the abrasive material grain size used for lapping. Recommendations for selecting the abrasive material grain size for the lapping operation for the most common values of the roughness parameters for the working surfaces of spherical washers have been formed. In the article was proposed to introduce into the technical requirements for the spherical washers drawings changes concerning the gap size allowable in the conjunction, and as well as tolerances value changes of the radii of the working surfaces of the washers, thus increasing their manufacturability without conflicting with the requirements of the current standards

Transforming growth factor beta-1 (TGFB1) and peak bone mass: association between intragenic polymorphisms and quantitative ultrasound of the heel

BACKGROUND: Variance of peak bone mass has a substantial genetic component, as has been shown with twin studies examining quantitative measures such as bone mineral density (BMD) and quantitative ultrasound (QUS). Evidence implicating single nucleotide polymorphisms (SNPs) of the transforming growth factor beta-1 (TGFB1) gene is steadily accumulating. However, a comprehensive look at multiple SNPs at this locus for their association with indices of peak bone mass has not been reported. METHODS: A cohort of 653 healthy Caucasian females 18 to 35 years old was genotyped for seven TGFB1 SNPs. Polymorphisms were detected by restriction endonuclease digestion of amplified DNA segments. RESULTS: The frequencies of the least common allele at G-800A, C-509T, codon 10 (L10P), codon 25 (R25P), codon 263 (T263I), C861-20T, and 713-8 delC loci were 0.07, 0.33, 0.41, 0.08, 0.04, 0.25 and 0.01, respectively. A significant association was seen between QUS Stiffness Index (QUS-SI) and the SNP at codon 10 and the linked promoter SNP, C-509T. This association remained significant after multiple regression was used to incorporate important clinical covariates – age, BMI, level of activity, family history, and caffeine intake – into the model. CONCLUSION: The association of QUS-SI with -509T is consistent with a gene-dose effect, while only individuals homozygous for the codon 10P allele showed a significant increase. In this cohort of young healthy Caucasian females, the T allele at position -509 is associated with greater bone mass as measured by calcaneal ultrasound

Betacellulin inhibits osteogenic differentiation and stimulates proliferation through HIF-1α

Cellular signaling via epidermal growth factor (EGF) and EGF-like ligands can determine cell fate and behavior. Osteoblasts, which are responsible for forming and mineralizing osteoid, express EGF receptors and alter rates of proliferation and differentiation in response to EGF receptor activation. Transgenic mice over-expressing the EGF-like ligand betacellulin (BTC) exhibit increased cortical bone deposition; however, because the transgene is ubiquitously expressed in these mice, the identity of cells affected by BTC and responsible for increased cortical bone thickness remains unknown. We have therefore examined the influence of BTC upon mesenchymal stem cell (MSC) and pre-osteoblast differentiation and proliferation. BTC decreases the expression of osteogenic markers in both MSCs and pre-osteoblasts; interestingly, increases in proliferation require hypoxia-inducible factor-alpha (HIF-α), as an HIF antagonist prevents BTC-driven proliferation. Both MSCs and pre-osteoblasts express EGF receptors ErbB1, ErbB2, and ErbB3, with no change in expression under osteogenic differentiation. These are the first data that demonstrate an influence of BTC upon MSCs and the first to implicate HIF-α in BTC-mediated proliferation

Utrzymanie ruchu – identyfikacja i analiza luki kompetencyjnej

The efficiency of maintenance processes in an enterprise largely depends on ensuring adequate resources for its implementation. The main factor that affects the quality of these processes is competent employees. Their knowledge, skills and ability to respond to unexpected situations largely determine the efficiency of the functioning of the technical infrastructure in an enterprise. In the light of the prospects for the development of the Industry 4.0 concept, and, thus, for the development of highly automated systems, the demand for qualified maintenance employees will increase. Therefore, in order to ensure the right level of competency of maintenance workers, through the proper assessment and identification of their competency gap, is an important task of managers. In many enterprises this is not implemented. The aim of the presented work was to developed a comprehensive model of the competency assessment of maintenance workers. The implementation of the developed model enables the identification of the current level of employees’ competencies and identification of the competency gap, as well as it allows to assess the effects of a failure to meet the required level of competency. Additionally, the results of the identification of the real activities taken by the surveyed enterprises concerning the competency assessment of maintenance services employees are presented in this article. The study was carried out in manufacturing enterprises in different industries on a specific area. The results were analysed and presented in a graphic form.Efektywność działań utrzymania ruchu w przedsiębiorstwie w dużej mierze zależy od zapewnienia odpowiednich zasobów do jego realizacji. Podstawowym czynnikiem, który ma wpływ na jakość realizacji tych działań są kompetentni pracownicy. Ich wiedza, umiejętności i zdolności reagowania na nieprzewidziane sytuacje, w dużej mierze decydują o sprawności funkcjonowania posiadanej infrastruktury technicznej w przedsiębiorstwie. W świetle perspektyw rozwoju koncepcji Przemysł 4.0, a tym samym rozwoju wysoce zautomatyzowanych systemów, wzrośnie zapotrzebowanie na wykwalifikowanych pracowników utrzymania ruchu. Dlatego ważnym zadaniem menedżerów przedsiębiorstw jest zapewnienie właściwego poziomu kompetencji pracowników utrzymania ruchu, poprzez ich odpowiednią ocenę i identyfikację luki kompetencyjnej, co w wielu przedsiębiorstwach nie jest realizowane. Celem przedstawionej pracy było opracowanie kompleksowego modelu oceny kompetencji pracowników utrzymania ruchu. Zastosowanie opracowanego modelu umożliwi identyfikację aktualnego poziomu kompetencji pracowników, identyfikację luki kompetencyjnej, jak również pozwoli ocenić skutki niezapewnienia wymaganego poziomu kompetencji. Dodatkowo w pracy przedstawiono wyniki badań, których celem było zidentyfikowanie rzeczywistych działań realizowanych w przedsiębiorstwach w zakresie oceny kompetencji pracowników służb utrzymania ruchu. Badania przeprowadzono w przedsiębiorstwach produkcyjnych, w różnych branżach przemysłu na określonym obszarze. Wyniki badań opracowano i przedstawiono w postaci graficznej

The improvement of vendor assessment process based on the example of production company

In many cases the quality of the products depends of the materials which were used to the production process. That's why many companies, which are carry out of the high quality of products, want to have good relations with their vendors. The organizations, which has implemented the quality management system according ISO 9001 standard are obligated to fulfillment the requirements according point 7.4 this standard . purchase process. The elaborating the right method of vendors assessment is the one of the most important tasks of continues improvement in the production company. In the article the analysis and improvement of vendor assessment process based on the example of production company was presented. This company produce the connection elements and cardboard packages. Its polish company which sells products on polish and European market. The analyze was made in the following steps: - the analyze of the actual method of vendors assessment, - the classification of the vendors according to the actual assessment criteria, - the analyze of vendors assessment points, - the identification of the drawbacks of the actual assessment method, - the proposals of the new possibilities (solutions) of the assessment, - the classification of the vendors according to the new assessment criteria, - the analyze of vendors assessment points according to the new method. This method can show the right directions of working in the company. This method can help to: - choose the right types of assessment criteria, - elaborate the points scale, - allocate the adequately importance of criteria, - choose and find the properly assessment method, - can help rightly interpretation of the assessment scores. Although the new method will help the company to identify the best vendors. This vendors will deliver the best quality materials with favorable price

Problems of Modern Methods Implementation of Stock of Technological Machines Management

Productive management of possessed infrastructure is one of the factors that determine competitiveness specific efficiency and production ability. In fact, the proper operating of devices in the enterprise is a very important element of system of machine operation management. Proper operating demands specific actions due to having certain production demands, priorities and supervision. Issues connected with traditional and modern stock of machine tools management were presented in this paper. Methods of technical infrastructure management of enterprise and their advantages and drawbacks were discussed too. Special importance is given to TPM - an innovative approach towards machine operation, the reduction of stoppages and elimination of sources of wastage. Key aspects of TPM implementation process which requires eg. systemic everyday work (5S), were presented. Beside technical and personal problems, the area of fulfilling the rules of safe work with machining devices was discussed. Stages of searching for incompatibilities, generating of necessary documents and establishing essential areas of technical condition of machines conditions were showed

Wyniki badań dotyczących identyfikacji działań realizowanych w zarządzaniu infrastrukturą techniczną w dużych przedsiębiorstwach

Działania realizowane w zakresie nadzoru nad infrastrukturą techniczną są szczególnie istotne dla dużych przedsiębiorstw. Powszechnie panuje przekonanie, że w dużych przedsiębiorstwach istnieje duży zakres zadań realizowanych w ramach nadzoru nad infrastrukturą techniczną. Dotychczas przeprowadzone badania wskazują jedynie na stosowane w przedsiębiorstwach strategie nadzoru nad maszynami, jednakże nie wskazuje się, jakie działania są konkretnie realizowane. W rzeczywistości mimo zasad przyjętych dla każdej strategii w praktyce nie są one tak do końca stosowane. Celem badań, których wyniki przedstawiono w niniejszej pracy, było zidentyfikowanie rzeczywistych działań, które są prowadzone w przedsiębiorstwach w zakresie nadzoru nad infrastrukturą techniczną w dużych przedsiębiorstwach. Badania dotyczyły przedsiębiorstw produkcyjnych funkcjonujących w różnych branżach przemysłu na określonym obszarze. Wyniki badań opracowano i przedstawiono w postaci graficznej. Wyniki badań wskazują zarówno na te działania, które są powszechnie realizowane, jak i na te, które rzadko występują w tej grupie przedsiębiorstw.The activities realized within the technical infrastructure supervision are particularly important for large enterprises. It’s commonly believed that in large enterprises there is a wide range of tasks realized within the technical infrastructure supervision. The studies done so far indicate only the machine supervision strategies used in enterprises, yet it doesn’t indicate what activities are specifically realized. In fact, in spite of the rules adopted for each strategy, they are not used entirely in practice. The aim of the survey, of which the results are presented in this paper, was to identify the real activities conducted in enterprises within the technical infrastructure supervision in large enterprises. The survey concerned production enterprises functioning in different industries on a specified area. The results were drawn up and presented graphically. The results indicate both the activities which are commonly realized and those which are rare in this group of enterprises