Excavator Bucket Research Articles

New type of high-strength flexible cover plate to prevent engineering failure in oil and gas pipeline engineering

Reinforced concrete cover plates are the main engineering protection measure for oil and gas pipelines in densely populated areas with high consequences. However, they have disadvantages such as high cost, difficult construction, long construction time, and inability to promptly and effectively warn mechanical operators. On-site excavation tests were carried out in order to verify the warning performance and impact resistance of a high-strength flexible cover. In the warning performance verification test, when an excavator hits the high-strength flexible cover plate set above the oil and gas pipeline during operation, the excavator driver should immediately receive obvious warnings that there are obstacles underground and that the digging should be stopped immediately. In the impact resistance verification test, the high-strength flexible cover plate should provide sufficient mechanical protection to withstand the penetration of the cover plate by an excavator weighing at least 30 tons and to avoid the damage of a pipeline below. At the same time, it is necessary to determine the one-time impact depth of the excavator bucket by designing the working condition under which the high-strength flexible cover is not buried in the soil, and is affected by the vertical action of the excavator bucket. This depth value serves as an important data support for the minimum safety distance between the high-strength flexible cover and the oil and gas pipeline. This paper proposes the application of a new type of the high-strength flexible cover plates instead of reinforced concrete cover plates above pipelines. Field tests verified the important role of the high-strength flexible cover plates in the protection of oil and gas pipelines. When long-distance oil and gas pipelines pass through densely populated high-consequence areas, they can replace traditional reinforced concrete cover plates to achieve an effective pipeline protection. At the same time, they have a simple structure, their construction is convenient, they are reliable and stable, and economical and rational. By using the high-strength flexible cover plates, savings that exceed 70% of the project investment may be achieved.

Method of State and Residual Resource Assessment of Excavator Bucket Tooth Caps

Method of State and Residual Resource Assessment of Excavator Bucket Tooth Caps

AC Electric Drive for Opening the Bottom of an Excavator Bucket

AC Electric Drive for Opening the Bottom of an Excavator Bucket

ANALYSIS OF THE OCCUPATIONAL ACCIDENTS CHANCE IN MINING, PROCESSING, AND WHORKSHOPS AT PT. LEMON ISLAND, SOUTH MANOKWARI DISTRICT, MANOKWARI REGENCY

The importance of task identification using the job safety analysis method is to detail the works based on work sequences and risks possibly arising. Job safety analysis can be used as a first step to find out the potential accident and to make accident controls. The results show that the potential accidents can be identified based on their severity. High risk, causing physical disability to death, occurs in gravel processing work using jaw crusher, gravel hauling, concrete mixing, and casting. Moderate risk, causing treatments at the hospital, includes welding, repairing excavator buckets, stacking and tidying material, screening stones and sand, and cutting iron. Low risk, which can be handled with first aid, includes excavating material, loading, painting iron frame, curling and straightening iron, repairing bulldozer body, repairing bulldozer machine, repairing dump truck glass, replacing dump truck coupling, replacing dump truck tires, replacing dump truck brake, repairing dump truck bucket, repairing excavator engine, repairing excavator crawler, and repairing the engine of concrete pump trucks. In addition, PT. Pulau Lemon has not properly implemented the use of personal protective equipment and work protective equipment for their worker, therefore it is still needed to do some required improvement.

Research of the Dependence of the Pipeline Ends Displacement Value When Cutting Out Its Defective Section on the Elastic Stresses in the Pipe Body

In the process of repairing main oil and gas pipelines with cutting out defective sections, due to the elastic stresses in the body of the pipeline at the end of the first cut, there is a sharp displacement of the pipeline ends on both sides of the cutting site. This sharp displacement poses a threat to the lives of workers, and also complicates the further process of welding a new section of the pipeline due to the need to center its ends relative to each other. At the same time, to reduce the displacement of the ends of the pipeline, it is often pressed down with an excavator bucket before cutting, which contradicts the safety rules for conducting repair work. This article examines the dependence of the displacement value of the ends of the pipeline on the existing elastic stresses in it in order to substantiate the need to take into account the elastic stresses in the body of the pipeline in the used repair methods, as well as the need to develop safe and technologically efficient equipment for fixing the position of the pipeline before cutting and further centering its ends relative to each other.

Increasing the Resource Capabilities of Technological Machines in Reclamation Works

The need for repair actions was determined depending on the resource of technological machines and their parts. On the example of an excavator bucket, directions for increasing resource capabilities are shown.

Mathematical model of soil digging spherical excavator bucket

Introduction. The article presents a new design of a bucket of a single bucket hydraulic excavator, which allows you to increase the performance of these machines. Increased efficiency is achieved due to the installation of buckets of larger volume without changing characteristics of hydraulic drive. The purpose of the presented work is to select the volume of the spherical ladle for the digging process. The task of research is to obtain the dependencies of ladle and soil speeds on the parameters of the digging process. Selecting the volume of the spherical ladle will determine how much it can be increased compared to the volume of the serial ladle to carry out the digging process.Materials and methods. The process of digging a new bucket was considered in the form of a two-scale KelvinVoigt rheology model. This model was described by a system of second-order differential equations. The system solved the Cauchy problem, which made it possible to determine the general solution of the equation satisfying the two equations of the system. As a result, derivatives from ladle and soil movements were determined, which are nothing more than ladle and soil speeds.Results. The solution of the above system made it possible to obtain dependencies of ladle speeds and soil masses on parameters of the digging process. The digging process is possible at positive speed values. When substituting depending on the process parameters under the condition of velocity positivity, you can determine the volume of the spherical ladle.Practical significance. To simplify and put into practice the obtained dependencies, an algorithm was compiled to calculate the volume of the spherical ladle. The presented algorithm can be implemented in a computer program.

The evaluation of forces acting on excavator bucket and its capacity

Excavators are commonly used machines in mining, material transport operations, ground levelling, agriculture, forestry applications and construction. The design of an excavator hoe type bucket is a critical task in the context of the digging forces developed by the actuators during the digging operation (Material Removing). The bucket is a highly essential component of the backhoe loader since it carries the entire load of excavated material. The important criteria for the design to be safe is that, the digging forces of the actuators must be greater than the resistive force offered by the terrain to be excavated. Due to an excessive quantity of resistive loads, an adverse effect on the bucket parts occurs, and it may fail during excavation operations. The bucket is being held back by a variety of forces that are preventing it from moving into the soil such as gravitational force and remolding force. This method can be used to predict digging forces and to run an excavation task autonomously. Bucket capacity, bucket life, poor design of tool, results in weak excavation of the ground, high wear of the tool, wastage of the time and power thus reducing the productivity and efficiency of a product. Prediction of resistive forces is a difficult task so soil tool interaction model plays an essential role also soil parameters such as density, cohesiveness differs as per material type. As the resistive forces are applied, steps such as penetration, separation, and escape are considered. The resistive forces for the worst soil condition characteristics have been estimated here. The reformulated basic Fundamental Earth Moving Equation,considers the terrain slope and interaction of the bucket as it moves through the soil. It is modified to support inclined soil surfaces and transient tool motion states. This paper focuses on the method of evaluating bucket capacity and digging forces, as well as the resistive forces provided by stiff soil, in accordance with ISO and SAE standards.

Electric drive for opening the bottom of the excavator bucket

Electric drive for opening the bottom of the excavator bucket

Influence of rock type on regularities of excavator bucket tooth crown wear

Influence of rock type on regularities of excavator bucket tooth crown wear

Increasing in service durability of excavator bucket teeth by alloying in casting mould

Effective technology for producing of bucket teeth for increased operational durability excavators is described. Surface alloying of working elements in casting mould by wear-resistant PG-S27 powder and hardening of fastening holes by painting with fi ne chips of high-manganese steel are used. Production tests have shown the advantages of excavator bucket teeth cast using the proposed technology in comparison with steel 110G13L excavator bucket teeth using traditional technology. The prime cost of 1 ton of castings made according to the developed technology turned out to be significantly lower than prime cost of 1 ton of casting produced according to the traditional technology.

Ірі түйіршікті топырақты өңдеуге арналған грейферлі экскаватордың жаңа жұмыс жабдығының негізгі параметрлерін негіздеу

Traditional designs of working bodies of earthmoving machines are not adapted for the development of large-block soils of mudslides and other blockages in emergency situations, which leads to a decrease in their productivity. Therefore, it is necessary to create special working bodies of single-bucket excavators for the development of mudflows with large-block inclusions, allowing to expand the functionality of these machines. The subject of the study is to determine the kinematic and power parameters of the mechanism of extension of a special working body of an excavator based on analytical studies and computer modeling. The article proposes a method for determining the links of the mechanism of a special excavator working body and algorithms and methods for determining the positions, coordinates of the points of the links. As result of the study there have been obtained closure equations of independent contours of the jaw extension mechanism of a special excavator bucket in vector form for determining angular velocities and accelerations of the links and numerical and graphical parameter values.

METHODS OF LAND PREPARATION TO DELAY GANODERMA OR BASAL STEM ROT (BSR) DISEASE IN OIL PALM REPLANTING IN INLAND MINERAL SOILS - EXPERIENCES AND OBSERVATIONS

Three methods of land preparation in oil palm replanting are described, attempted and observations recorded for a period of 11 to 14 years. In method A carried out in 2006 replanting, the land was prepared by excavating only the stumps of Ganoderma infected fallen and vacant palms through the construction of pits. Here, after 11 and 12 years of replanting resulted in 18 and 21 per cent of BSR infections respectively, while, after 14 years the infection increased to 28.5 per cent in the same replants. In method B, comprising of two fields replanted in 2009 and 2008 after clean clearing or 100 per cent removal of boles of living, dead and vacant palm points followed by two rounds of thorough disc ploughing and single rotovating of the soil, showed 5.8 and 8.5 per cent of Ganoderma infections after 11 and 12 years, respectively. Although method C was a slow and expensive operation, 100 per cent excavation of living, dead and vacant palm boles followed by deep ploughing or tilting of the soil with the excavator bucket showed 2 per cent Ganoderma disease after 11 years of replanting. Among the three modes of land preparation, methods B and C showed a delay in infection of Ganoderma in replants compared to method A. The excavator bucket used in method C for deep tilting prompted the search for other tools like Howard ripper and fabricated steel ripper mounted on a bulldozer, of which the latter was found suitable and has been implemented commercially. However, the cost of such operation was 2.6 times (i.e. RM2 030 against RM769 per hectare) higher than the preparation of land by method A in replanting. Another study was conducted to understand the relationship between the visually observed Ganoderma palms and normal appearing palms with Ganoderma infection at the sub-clinical level. This may be helpful for planters to predict the total Ganoderma infected palms present in the field prior to replanting. The relationship appeared to be a cubical expression between the visual and total Ganoderma population in a field prior to replanting. Keywords: Ganoderma disease, basal stem rot, clean clearing, land preparation, replanting, deep ploughing.

Restoration and alloying of working bodies of earth-moving machinery

During the operation of road-building and earth-moving machinery, their working bodies are subjected to the greatest wear, in particular: crowns of rippers, blades of dumps, teeth of excavator buckets. The limiting state of parts is characterized by a 2535 % loss of mass of worn elements of working bodies that have direct contact with the ground. Rejected during repair parts are sent for recycling or restoration. The service life of some of the most loaded parts when working with heavy soils is several hours. The need for crowns for earthmoving equipment from enterprises involved in road construction and quarrying in the Far East region is measured in tens of thousands of pieces per year. Replenishment of stocks of wear parts makes it necessary to implement complex logistics schemes due to the remoteness of facilities from the centers of production of parts, and is always accompanied by significant costs. Therefore, the problem of restoring and strengthening worn crowns of rippers and teeth of excavator buckets is very relevant. Various industrial and scientific organizations have been solving this problem for a long time, and quite good results in this direction were obtained after a number of developments at the E.O. Paton Electric Welding Institute in the direction of the method of electroslag facing (ESF). Based on this method, various technological processes for the restoration of massive parts were created. The use of ESF allows not only to restore parts with significant wear, but also to obtain the corresponding design requirements or improved functional properties. These, when restoring the working bodies of construction and road vehicles, will increase their durability. The paper considers the possibility of restoring worn crowns of working bodies of earth-moving vehicles by the ESF method, using ore concentrates mined in the Far East as alloying additives.

Design and analysis of biomimetics based excavator bucket and tooth

Within the scope of this paper, various bucket tooth designs and a biomimetic bucket design were created in order to produce a solution on digging efficiency which is one of the general problems of construction machines. These designs were inspired by giant anteater and American badger front claws. The inspiration aspect was diversified by integrating the paw and claw curves of the giant anteater and by bringing American badger claws into the design in different ways. Furhermore, the designed biomimetic bucket alternatives were compared between each other and the standard bucket equipment used in the market by making a computer aided static analysis. The compared criteria were the equivalent stress and total deformation formed on the bucket itself, the excavation equipment and the excavated soil. According to the analysis results, when the bucket tooth named P2 is mounted to the standard bucket, it has 42% lower Von-Mises stress on than standard bucket tooth. Additionally, it is exposed 4,7% less total deformation than standard tooth. Also, in terms of maximum Von-Mises stress formed on the soil model, P2 causes 17,5% greater stress than the standard bucket tooth.

Analysis of the Effects of Failure of a Gas Pipeline Caused by a Mechanical Damage

Natural gas continues to be one of the basic energy sources used as fuel in the power sector, in industries and in households. The potential and attractiveness of this fuel is gaining special significance in the current energy transitions from coal-based power engineering to power generation based on renewable energy sources. Natural gas is supplied to consumers mainly through a network of pipelines, which ensures a relatively high reliability of the supply. Still, failures occur due to the corrosion of pipeline walls, material defects or human errors, which can result in uncontrolled release of gas. The released gas can trigger dangerous phenomena, such as fires and explosions. This paper presents an analysis of the causes and effects of damage to a medium-pressure pipeline caused by earthworks carried out within an area where a pipeline is located. Holes in the pipeline due to the impact of an excavator bucket are analysed. The impact of the excavator bucket may cause a rupture equal to 50% of the pipeline’s cross-sectional area. Hazard zones related to fires and explosions due to the released natural gas are presented. For the analysed pipeline with a diameter of 0.5 m and a gas pressure of 5 MPa, the range of hazard zones arising due to pipeline damage caused by an excavator bucket can reach about 200 m.

РАБОЧЕЕ ОБОРУДОВАНИЕ ЭКСКАВАТОРА ДЛЯ ВЫБОРОЧНОГО РЕМОНТА ТРУБОПРОВОДА

Work objective. Modernization of the excavator's working equipment design intended for islands of pipeline repair together with confirmation of its operability by checking the machine for stability, carrying out the necessary calculations of the hydraulic system.
 Methods. The main idea is in accessorizing the main working equipment of the excavator with a structure consisting of three teeth, which is in a body with an excavator bucket form a pickup mechanism. To confirm the operability of the proposed design, theoretical studies have been carried out aimed at determining the stability of the machine for the most dangerous design operating positions, and permissible pipe sizes have been established so that working with these sizes provides the stability of the machine. 
 Results. A variant of improving the design of the excavator working equipment of the third size group has been developed. The equipment is intended for carrying out random repair of the pipeline by the excavator without involving other road construction equipment (for example, a pipelaying crane). The proposed design of the working body allows speeding pipeline repair by reducing the time spent on changing or relocating the equipment, which as a result reduces the cost of repair work.
 Conclusions. Calculations of the excavator hydraulic system have been carried out. In addition, as a result of theoretical studies, calculated dependences have been obtained, which made it possible to establish the stability coefficient of the excavator of the third size group when working with upgraded equipment and the pipeline diameter in the range of 720 ...1420 mm. As a result of the research, it was found that the proposed equipment is effective for carrying out random repairs of pipelines with diameters of 720, 1020 and 1220 mm. The stability of the machine in the most dangerous positions is being carried out. The calculation shows that when the excavator does demolition works of a pipeline with a diameter of 1420 mm, there is a danger of overturning the machine due to a decrease in the Ku coefficient below the permissible value.

Design Based on Changing the Bucket of Small Hydraulic Excavator to Clamp Brick Machine

Small hydraulic excavators have the characteristics of multi-function and wide application range. It is an important mechanical equipment widely used in mechanized construction. It can not only be used for excavation of earth and stone, but also plays an irreplaceable role in various engineering constructions. Moreover, through the replacement of working devices, it can also be used for various operations such as lifting, loading, grabbing, piling, and drilling. This article takes a small excavator as an example. By disassembling the original bucket, the newly designed brick clamping mechanism is installed in the position of the bucket, so as to realize the purpose of clamping or moving bricks and increase the scope of use of the original excavator.

Evaluating the impact of excavator bucket capacity on the output of a haul truck in different variants of their positioning

When studying the influence of excavator bucket capacity on haul truck loading time, it is necessary to assess the technical and economic performance of the complex. If the cost of the machine shift of the complex will not cover the increase in productivity, then it is inexpedient to use this complex. This issue requires further, more detailed study and performance of detailed technical and economic analysis. Also, it is necessary to consider classical recommendations about ratio of excavator bucket capacity and haul truck body. It should be noted that at present, there is a significant divergence in the size range of excavators: powerful, with a large capacity bucket, rope shovels are used for mining the coalless zone; small maneuverable hydraulic shovels – for mining the coal-bearing zone. In this paper, we will try to combine the first and the second: consider hydraulic excavators with maximum bucket capacity, which is reasonable to use when mining overburden. In addition, a detailed study of the options of mutual arrangement of excavator and haul truck has not been performed until recently, this work is intended to fill this gap.

Numerical Evaluation of Contemporary Excavator Bucket Designs using Finite Element Analysis

Bucket is key and primary component of heavy construction machinery such as excavators. It has to bear high impact loads during digging process, resulting in large stress and deformations. This research work has been focused on reducing stress and deformations produced in excavator bucket due to digging. For this purpose, different design patents of excavator buckets (including ornamental designs) were considered. Various models of excavator buckets were developed by varying geometrical parameters such as number of blade teeth/tips and bucket curvature. Finite element analysis of these models was carried out by using ANSYS in order to determine stress and strains. Maximum values of Von Mises stress, principal stress, factor of safety and total deformation were evaluated numerically for all three-dimensional geometric models. Excavator bucket with least values of stress and deformations, but largest factor of safety, was identified through numerical computations. Mechanical performance of ornamental buckets having quarter circular curvature with 6 blade teeth was observed to be better as compared to designs having single blade strip or 5 blade teeth. Mass reduction up to 2.5%, while the stress reduction and factor of safety enhancement up to 9.6% was achieved by incorporating 6 blade teeth in ornamental design of excavator bucket.