Lifting Equipment

Objectives To determine whether advice and training on working techniques and lifting equipment prevent back pain in jobs that involve heavy lifting. Data sources Medline, Embase, CENTRAL, Cochrane Back Group’s specialised register, CINAHL, Nioshtic, CISdoc, Science Citation Index, and PsychLIT were searched up to September-November 2005. Review methods The primary search focused on randomised controlled trials and the secondary search on cohort studies with a concurrent control group. Interventions aimed to modify techniques for lifting and handling heavy objects or patients and including measurements for back pain, consequent disability, or sick leave as the main outcome were considered for the review. Two authors independently assessed eligibility of the studies and methodological quality of those included. For data synthesis, we summarised the results of studies comparing similar interventions. We used odds ratios and effect sizes to combine the results in a meta-analysis. Finally, we compared the conclusions of the primary and secondary analyses. Results Six randomised trials and five cohort studies met the inclusion criteria. Two randomised trials and all cohort studies were labelled as high quality. Eight studies looked at lifting and moving patients, and three studies were conducted among baggage handlers or postal workers. Those in control groups received no intervention or minimal training, physical exercise, or use of back belts. None of the comparisons in randomised trials (17 720 participants) yielded significant differences. In the secondary analysis, none of the cohort studies (772 participants) had significant results, which supports the results of the randomised trials. Conclusions There is no evidence to support use of advice or training in working techniques with or without lifting equipment for preventing back pain or consequent disability. The findings challenge current widespread practice of advising workers on correct lifting technique.

One of the differences between industrial manufacturing or processing plants and construction sites is the temporary nature of the construction site, which has traditionally precluded installation of sophisticated production monitoring systems. Monitoring of pro- duction progress, cost, and quality is performed almost exclusively manually, with the result that it is expensive and approximate, and is commonly delivered with a time lag that does not allow for an effectively closed control loop. Automated monitoring of construction lifting equipment to provide useful feedback information for project management is a strong potential candidate; almost all components and materials must be transported by machines, and monitoring of machines is relatively straightforward. A system concept, employing a "black box" monitor and an electronic building information model, was developed. A field study was conducted to test the feasibility of the concept. The results indicate that the system is technically feasible, and offers the potential to deliver real-time, accurate project control information at very low cost.

The over-all objective of the research project Efficient Lifting Equipment With Extra High Strength Steel (LiftHigh) was to obtain a better utilisation of extra high strength steels, in this context defined as steels with yield strengths in the interval 460 - 1100 MPa, and thereby expand the limits for structural steels available for crane manufacturers as well as for other applications. The work within the project has included actions focusing on the fatigue resistance, the resistance to global and local buckling and development of methods for advanced design with non-linear FEM. A specific aim for the project was to show that using extra high strength steel makes it possible to obtain a 20-40 % reduction of weight for a given function. This aim is in accordance with the desire amongst the crane users, which also was proven by an enquiry performed in the early beginning of the project. The enquiry showed that the opinion among crane users was that a decreased crane weight should be the first priority for future development. Examples on how to use FEM for design are given in Chapter 5 of this report, covering generation of finite element models, determination and application of appropriate geometrical and structural imperfections, conduction of static calculations and evaluation of the results. In Chapter 6 it is shown, by redesign of an existing trolley structure and a telescopic boom, that it is possible to achieve a substantial weight reduction by using extra high strength steel. In these two particular examples the weight reductions were 38 % and 18 %. Concerning global and local buckling and fatigue, the conclusions are summarised in Sections 7.2 and 7.3. For global and local buckling, the experimental and theoretical investigations has covered cold formed rectangular and circular hollow sections, as well as welded square hollow sections. In short, the results obtained gives no indications that the design models already in use, for instance in EN 1993-1-5, for steels with regular yield strengths can not be applied also for high strength steels with yield strength up to 1100 MPa. However, regarding welded plates, the design rules in EN 1993-1-5 seem to slightly overestimate the resistance (concerning a modified slenderness greater than 0.9). For fatigue, it is concluded that the investigated steel grades fit to the detail categories given in EN 1993-1-9 and can be classified as good as mild steels although, for some details differences appear in the calculated slope of the S-N-curves. For these details a classification with slope m = 4 can be considered in EN 1993-1-9. As it is known from former investigations, the fatigue resistance is influenced by the design of the weld detail on the one hand and the quality and the execution of the weld on the other hand. In constructions where fatigue is the decisive factor, elevated concentration should be laid on the geometry of details and quality of the weld. In this context advantage can be also achieved using post weld treatment. Nevertheless, it has to be mentioned that with the same stress variation range, the fatigue loads of high-strength steels can be applied on a correspondingly higher level than it is possible for mild steels. This fact does not arise from the classification in detail categories, as it is carried out in EN 1993-1-9.

The slewing bearing of the full-revolving super large lifting equipment bears all loads above the rotating platform. Due to the effect of bending moment, the load conditions of the slewing bearing structure is complex and large, which leads to the non-uniform of stress and uneven deformation and final seriously affects the work performance of lifting equipment. The numerical example in this paper considers three kinds of sliding-friction models between slewing bearing structure and orbit. By numerical analysis results, we adjusted the structure arrangement and stiffness distribution. Finally the non-uniform of stress of the slewing bearing structure has been improved and tended to be uniform. Thus the paper presents a new approach for the design of the slewing bearing in super large lifting equipment.

It is known from the principle that the pump-vessel combined ore lifting method has high head, large ores lifting capacity, and long-term working reliability. When applied to the deep-sea rigid pipe mining system, the main pump and power equipment installed on the mining ship is more convenient to operate and maintain. According to Bernoulli's equation and two phases of hydrodynamics theory, the ore lifting equipment parameters have been calculated and analyzed. It is known that the pump head H of 1000 m sea mining system is 124-172 m and that of 5000 m sea mining system is 652-760 m. It is known that the pump-vessel combined lifting method is feasible in both theory and practice, therefore it is an ideal ore lifting method for a deep-sea rigid pipe mining system.

Recently, not only around Korea but also other countries shows a pattern of arising high-rise building construction project which was delayed or aborted during global economic crises and recession. Although the market starts to stretch, It is getting competitive to win a contract in high-rise construction project between contractors due to lack of competitive advantage especially to Korea contractors. To get that, Korean contractors needs lifting equipment plan. But currently, they depend on the empirical methods and that cause schedule delay, not controlled cost management problem. Therefore, this research is to improve the accuracy of Lifting plan by analyzing the current issues of Lifting plan system and deducing the types of failures with planning factors, as well as analyzing the impact on schedule and cost control and safety management by each failure mode. Also, by analyzing detail risk factors per Lifting Equipment with FMEA, to infer the critical risk factor on high-rise construction project.

A new kind of hydraulic lifting equipment for large load lifting and conveying is introduced.The operating principle,composition and features are presented as well as some specific applications,and on the basis,the trends in and improvement to this equipment are discussed.

Due to pipe-laying process changed for Offshore Oil 201 pipelay vessel requires to place sand blasting machine equipment in suite place, to meet the sand-blasting machine to complete the process of laying pipe work cycle which demands for subsea pipelines sandblasting, then the sand-blasting lifting equipment was designed. The equipment consists of a hydraulic lifting platform system, rail trolley system and control system. The experiments showed that the sand-blasting lifting equipment could securely connect with sand-blasting machine, the sand-blasting machine could be lift fast, installation fast in the suite place, meeting the production requirements.

At present,there are no any rules or specifications on how to detect and assess the internal quality of the lifting wire rope in all the current technical specifications and standards for the safety detections on the hydraulic facilities.The necessity,main study content and main study methods of the research made on the weak electromagnetic method based technology of the flaw detection on the wire rope of hydraulic lifting equipment for hydraulic facilities are expounded herein.It is pointed out that a "technical rule for flaw detection on internal quality of wire rope of hydraulic lifting equipment for hydraulic facilities" must be compiled,so as to guide the detection on the internal quality of the wore rope for ensuring the safety operations of the lifting equipment(on-service ones or new ones) concerned.

To meet the urgent demand of maintenance and lifting equipment for wind turbine, combined with designation demand, two kinds of primary structure of the maintenance and lifting equipment has been proposed, analyzed and compared. By means of the Solid Works software the initial design on the two kind of the machine, the self-climbing crane and the trailed hoisting platform, have been conducted, the static analysis has been performed based on the mechanics model, and the advantages and disadvantages of these methods have been pointed out and compared in the paper. Compared with the self-climbing crane, the mechanical structure of the trailed hoisting platform is simpler, the control system presented more reliable, simple, easier realized etc, and the cost is lower. The self-climbing crane is high-automatic, but the design of crane high in the free degree and high in difficulty, and the climbing force focused on the wind turbine tower is too large. Conclusion The trailed hoisting platform is determined as the main design method to design the maintenance and lifting equipment for wind turbine.