JUSTIFICATION OF THE STRUCTURE OF THE CRANE WHEEL WITH ELASTIC INSERT

The article considers the modernized design of the crane running wheel with anelastic insert.The purpose of the study is to substantiate the rational design of the running wheel onthe basis of determining the dynamic forces that occur when moving the truck and the crane bridge.Crane equipment is of great importance for the mechanization of lifting and transportoperations in various industries. Bridge cranes perform various lifting and transport operations.Installation and dismantling of equipment and machines. Also take part in the technologicalprocess of the metallurgical industry.The costs associated with the replacement and restoration of the running wheels are 15-17%of the cost of repairing the entire crane. At the same time more than 90% of crane wheels fail due towear of flanges.The main tasks for the diagnosis of crane wheels and rail tracks are usually solved duringscheduled maintenance by visual inspection of the wheel and rail and identify their wear. But thisdiagnostic tool does not quite satisfy the modern conditions of the cranes, namely, the compatiblecondition of the wheels and rails is not assessed, and it is impossible to carry out such controlconstantly during operation.Mechanisms for moving bridge cranes have several designs. The mechanism for moving thetruck, as a rule, has one drive, which transmits motion to the two drive wheels. The mechanisms ofmovement of the crane can be with the central and separate drive. The mechanisms of movement with the central drive can be with a low-speed transmission shaft, with a high-speed transmissionshaft and with a medium-speed transmission shaft.With this design, the gearbox shafts are connected to the drive wheel shaft by means of aclutch and a transmission shaft. This impairs the operation of the entire mechanism, because thepresence of the transmission shaft increases the complexity of the manufacture of the crane and itsweight and requires a very precise installation.To overcome these shortcomings, a separate drive of the end beams of the bridge is used.If the load on one of the support beams of the bridge is less than on the other, the enginespeed on this support increases and the support begins to run forward relative to the more loadedsupport. But the first engine begins to receive increased load, which is transmitted through themetal structure of the bridge and unloads the engine of the second support, due to which the speedof the first engine decreases and the speed of the second engine increases until they are equalized.Thus, in the process of moving the crane with a separate drive is the redistribution of loadbetween the two engines. Although the scheme of the mechanism with separate drives requires twoengines, two brakes and two gearboxes, it is the cheapest, light weight and easy to manufacture.The design of running wheels of cranes and crane carts should exclude a possibility ofderailment of wheels. To do this, the running wheels have two side flanges - flanges, which serve toguide the running wheels on the rails.The dynamic forces that arise when moving the trucks of cranes are quite large and cannot beignored when designing cranes. Most of all, they are manifested by wear of wheels and rails duringthe occurrence of distortions on the cranes.Thus, improving the performance and operational reliability of crane running wheels is avery important task of modern crane construction.The research technique is based on analytical methods of research of dynamic efforts in themechanism of movement of the truck of the bridge crane. The decision of three mass dynamicschemes of movement of the cargo cart is received.The analysis of the received decisions showed that at application of a running wheel with anelastic insert, dynamic factors at movement of the truck decreases. Dependences for determinationof dynamic forces which arise at movement of a running crane wheel taking into account rigidity ofan elastic ring which is inserted into a running wheel are received. The design and a technique ofcalculation of a running crane wheel with the vulcanized ring are offered.

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INCREASE OF OPERATING RELIABILITY OF THE TRAVEL WHEEL USING THE USE OF THE ELASTIC INSERTS

EUREKA Physics and Engineering ◽

10.21303/2461-4262.2020.001387 ◽

2020 ◽

Vol 5 ◽

pp. 69-76

Author(s):

Nataliia Fidrovska ◽

Evgen Slepuzhnikov ◽

Oleksiy Larin ◽

Ivan Varchenko ◽

Voloymyr Lipovyi ◽

...

Keyword(s):

Rational Design ◽

Theoretical Data ◽

Operating Mode ◽

Operational Reliability ◽

Overhead Crane ◽

Dynamic Factors ◽

Repair Costs ◽

Urgent Task ◽

Dynamic Forces ◽

Crane Wheel

The aim of research is to substantiate the rational design of the travel wheel based on the determination of the dynamic forces arising from the movement of the freight carriage and the crane bridge. The research methodology is based on analytical methods for studying dynamic forces in the mechanism of movement of the cargo carriage of an overhead crane. The obtained solution of the three-mass dynamic scheme of the movement of the freight carriage. To verify the theoretical data obtained, an experiment was carried out on an overhead crane with a lifting capacity of 5 , span of 22.5 m, lifting height of 8 m, operating mode of 7 K. The study of the vibration state was carried out on the crane beam in the middle of the span, on the axis of the driven wheel of the crane trolley with an elastic insert and on the axis of the drive wheel of the crane trolley of a conventional design. Crane wheels are the fastest wearing parts of a crane. A decrease in their durability leads to an increase in repair costs and crane downtime. Therefore, increasing the durability of crane travel wheels is an urgent task of modern crane construction. All designs of travel wheels are quite rigid and do not perceive shocks and distortions arising from the deviation of the rail track from the recommended values and lead to significant wear of the flanges and rails. The analysis of the obtained solutions showed that when using a travel wheel with an elastic insert, the dynamic factors during the movement of the freight carriage decrease. Dependences are obtained for determining the dynamic forces arising from the movement of the travel crane wheel, taking into account the rigidity of the elastic ring, which is installed in the travel wheel. The analysis of the regularities of the formation of vibration signs at different points of the overhead crane structure is carried out. The proposed design and calculation method for a travel wheel with an elastic insert improves its operational reliability

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Reciprocating internal combustion engines. Test code for the measurement of structure-borne noise emitted from high-speed and medium-speed reciprocating internal combustion engines measured at the engine feet

10.3403/01266755 ◽

2001 ◽

Keyword(s):

High Speed ◽

Internal Combustion Engines ◽

Internal Combustion ◽

Combustion Engines ◽

Medium Speed

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Reciprocating internal combustion engines. Test code for the measurement of structure-borne noise emitted from high-speed and medium-speed reciprocating internal combustion engines measured at the engine feet

10.3403/01266755u ◽

2015 ◽

Keyword(s):

High Speed ◽

Internal Combustion Engines ◽

Internal Combustion ◽

Combustion Engines ◽

Medium Speed

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Two-Phase Short Circuit in the Power Grid Powered by a Transformer with a Y/Δ-11 Winding Connection

Elektrotekhnologii i elektrooborudovanie v APK ◽

10.22314/2658-4859-2020-67-3-25-30 ◽

2020 ◽

pp. 25-30

Author(s):

Aleksandr S. Serebryakov ◽

Vladimir L. Osokin ◽

Sergey A. Kapustkin

Keyword(s):

High Speed ◽

Short Circuit ◽

Relay Protection ◽

Electric Circuit ◽

Operational Reliability ◽

Research Purpose ◽

Industrial Complex ◽

Two Phase ◽

Short Circuit Currents ◽

Secondary Winding

The article describes main provisions and relations for calculating short-circuit currents and phase currents in a three-phase traction transformer with a star-triangle-11 connection of windings, which feeds two single-phase loads in AC traction networks with a nominal voltage of 25 kilovolts. These transformers provide power to the enterprises of the agro-industrial complex located along the railway line. (Research purpose) The research purpose is in substantiating theoretical equations for digital intelligent relay protection in two-phase short circuits. (Materials and methods) It was found that since the sum of instantaneous currents in each phase is zero, each phase of the transformer works independently. We found that this significantly simplifies the task of analyzing processes with a two-phase short circuit. In this case, the problem of calculating short-circuit currents in the traction network can be simplified by reducing it to the calculation of an ordinary electric circuit with three unknown currents. (Results and discussion) The article describes equations for calculating short-circuit resistances for one phase of the transformer when connecting the secondary winding as a star or a triangle. The currents in the phases of the transformer winding at short circuit for the star-triangle-11 and star-star-with-ground schemes are compared. It was found that when calculating short-circuit currents, there is no need to convert the secondary winding of the traction transformer from a triangle to a star. (Conclusions) It was found that the results of the research can be used in the transition of relay protection systems from electromagnetic relays to modern high-speed digital devices, which will increase the operational reliability of power supply systems for traction and non-traction power consumers.

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Use of running plates by floor housed rats: A pilot study

Laboratory Animals ◽

10.1177/00236772211036572 ◽

2021 ◽

pp. 002367722110365

Author(s):

Jessica Frei ◽

Marcus Clauss ◽

Daniela E Winkler ◽

Thomas Tütken ◽

Louise F Martin

Keyword(s):

Pilot Study ◽

Animal Experiments ◽

Feeding Experiment ◽

Running Wheel ◽

Running Wheels ◽

Rats And Mice

The outfit of husbandry facilities of, and the enrichment provided for, experimental rodents plays an important role in the animals’ welfare, and hence also for the societal acceptance of animal experiments. Whether rats and mice benefit from being provided with running wheels or plates is discussed controversially. Here we present observations from a feeding experiment, where rats were provided a running plate. As a pilot study, six identical cages, with three animals per cage, were filmed for six days, and the resulting footage was screened for the number of bouts and the time the animals spent on the plates. The main activities observed on the plate in descending order were sitting (18.5 ± 13.8 bouts or 8.0 ± 13.7 min/animal per day), standing (10.2 ± 11.6 bouts, 3.8 ± 4.2 min), running (8.2 ± 13.3 bouts, 10.1 ± 21.4 min), grooming (2.0 ± 2.8 bouts, 6.7 ± 25.7 min), sleeping (1.0 ± 2.6 bouts, 24.0 ± 61.8 min) and playing (0.5 ± 0.9 bouts, 0.1 ± 0.5 min). Most of these activities (91% of all bouts, 90% of total time) occurred at night, similar to previous studies on running wheel usage. The running plate seems well-accepted as cage enrichment, even though in further studies, the motivating triggers and the effects of long-term use could be evaluated more in-depth.

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Anticorrosion Protection of Welded Joints of Oil Pipelines

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.284.1129 ◽

2018 ◽

Vol 284 ◽

pp. 1129-1133

Author(s):

M.A. Ivanov ◽

P.A. Danilkin ◽

V.D. Kvashnin

Keyword(s):

Welded Joints ◽

High Speed ◽

Operational Reliability ◽

Polymer Coatings ◽

Mechanical Tests ◽

Technical Standards ◽

Oil Companies ◽

Oil Pipelines ◽

Metal Properties ◽

Protection Coating

Currently, a problem of destruction of field and interfiled pipelines is topical. One of effective ways to increase an operational reliability of pipes is to protect them with different coatings. To protect the inner surface of oil pipelines the polymer coatings are used which cover the full length except the end sections – zones of mounted welded joints. Oil companies are interested in development of a technology of metal coating applying to the end sections, which provides both reliability of protection system of inner surfaces of pipes, and workability and high speed of mounting of pipelines. This paper shows the analysis of protection methods of pipeline end sections. The tests of metallized coatings are held. We identified the significant shortcomings of metallized coatings. There is a held experiment on applying of corrosion resistant coating by surfacing. There are the calculated heating zones while the surfacing operation. We defined the minimum necessary length of section for applying the protection coating. A chemical analysis showed that the expected structure in a surfaced coating is an austenite with inclusions of ferrite and martensite. Metallographic research showed that the protection layer is fully melted with a base metal of a pipe and represents a homogeneous structure without pores and slag inclusions. Mechanical tests confirmed the compliance of pipe metal properties to the requirements of normative and technical standards.

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The mechanisms of ‘neck-like’ deformation in high-speed melt spinning. 1. Rheological and dynamic factors

Journal of Non-Newtonian Fluid Mechanics ◽

10.1016/0377-0257(88)85021-3 ◽

1988 ◽

Vol 30 (2-3) ◽

pp. 141-155 ◽

Cited By ~ 20

Author(s):

Andrzej Ziabicki

Keyword(s):

High Speed ◽

Melt Spinning ◽

Dynamic Factors

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The Effect of Strain-Rate Upon the Tensile Deformation of Materials

Journal of Engineering Materials and Technology ◽

10.1115/1.3443275 ◽

1975 ◽

Vol 97 (2) ◽

pp. 151-155 ◽

Cited By ~ 49

Author(s):

R. G. Davies ◽

C. L. Magee

Keyword(s):

Flow Stress ◽

Strain Rate ◽

High Speed ◽

Tensile Deformation ◽

Rate Sensitivity ◽

Al Alloys ◽

Reinforced Plastics ◽

Strain Behavior ◽

Static Testing ◽

Dynamic Factors

The tensile strength of seventeen engineering materials including steels, Al alloys, and fiber-reinforced plastics, has been determined at strain-rates from 10−3 to 103 sec−1. Variable effects on the stress-strain behavior were found in the different materials with the Al alloys showing minimal strain-rate sensitivity and the plastics highest. All results exhibit a logarithmic dependence of flow stress on strain-rate and thus the dynamic factors (ratio of dynamic to low rate or quasi-static strengths) are as dependent upon changes in quasi-static testing speed (∼1 in./min (0.42 mm/s) as they are to changes at high speed (50,000 in./min or 50 mph (22.35 m/s). No significant influence of strain-rate on elongation or reduction in area has been found for any of the materials. Steels, which comprise the majority of the presently investigated materials, exhibit a higher rate sensitivity for yielding than for higher strain deformation. It is shown that the flow stress results for these steels leads to an internally consistent scheme when (1) strength level and (2) strengthening mechanisms are properly accounted for.

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