Roller Conveyor Research Articles

Contribution to the development of supplementary guidelines of embodiment design for roller conveyors

Currently the focus of planning and designing intralogistic systems lies on the technical quality rating in the form of maximum fulfilment of the mechanical requirements. This compliancy is often achieved by oversizing the mechanical components. A re-orientation in designing such systems is especially necessary because of the multitude of electrically-driven components. The current guidelines for embodiment design for intralogistic systems are not sufficient to optimise such plants regarding their service conditions. That is why adapted statistical models have been developed with the help of DoE based on measurands. These models conduce to generate new guidelines for embodiment design for such plants.

Interfaced multidirectional small-scaled modules for intralogistic operation

Logistics Journal, Vol. 01, Iss. 01 - This article examines options of an innovative design of intralogistic systems by interfacing small-scaled modules. Current intralogistic systems are quite customized with unique solutions and small production lots. In most cases these systems feature a central main control. To offer highly individual solutions, thus meeting the demand of shorter life cycles, there is a need for more flexible material handling systems. Hence, identical small-scaled modules with integrated intelligence present a promising approach. Requirements and options are analyzed to develop a small-scaled module as a basis for a flexible intralogistic system. An essential requirement for a small sized module is functional flexibility to allow configuring individual intralogistic solutions. Thus, these modules have to combine a variety of functions to provide not only a material flow function but also sorting and distributing functions, for instance. Furthermore, an easy extension of the system in any plane direction should be possible. Approaches based on existing technology, such as roller conveyors or belt conveyors are considered along with new solutions concerning this ambitious challenge. A further development of swivel wheel technology and some new ideas like a swivel disk present promising solutions. With a flexible mechanical solution we can design modules that can be developed into self controlling elements.

평면 디스플레이 기판 운송용 롤러 컨베이어 주위의 유동장에 관한 수치해석 연구

Flow field in a roller conveyor system, induced from the movement of a cassette in which glasses for flat panel display are loaded, is numerically studied in this paper. Contamination on the glass surface by dust particles produced from mechanical friction between roller and cassette is predicted from the analysis results of flow fields. Results show that a large swirl flow is formed under the moving cassette with constant speed. This swirl flow is confined only under the cassette because two main streams from the backward and the fan filter unit on the top ceiling are sufficiently strong. Therefore, it can be said that possibility of the contamination by the particles originated from the friction is relatively low. It is also revealed that flow direction between glass plates is changed according to the speed of the cassette movement due to the shear force of glass plates.

Hazard Analysis of Listeria monocytogenes Contaminations in Processing of Salted Roe from Walleye Pollock (Theragra chalcogramma) in Hokkaido, Japan

Hazard analysis of Listeria monocytogenes contamination during processing of salted walleye pollock (Theragra chalcogramma) roe was performed for a seafood plant in Japan from December 2005 to February 2006. As a result, L. monocytogenes number was detected on the pallet used for transport of barrels in the salting process and one of the rollers of the roller conveyor, which rotates while in contact with the bottoms of the barrels, but was not detected in any raw materials, interim products or final products. Thus, we believe that the pallet contamination initially occurred because of insufficient washing, that it was passed on to the bottoms of the barrels and that it was then passed on the roller of the roller conveyor by cross-contamination. Therefore, it is possible that interim and final products may become contaminated by processing devices and machinery. In addition, we conducted an inoculation study designed at the 1/20 actual factory scale using interim products with or without artificial color and seeded with L. monocytogenes to observe changes in its growth. In the inoculation study, multiplication of L. monocytogenes during the salting process was not confirmed in the samples with artificial color.

Innovations at Workplace: Improvement of Ergonomics

New physical overload factors (as working in the compulsory position or monotonously, where the strain of muscles is one-sided) have appeared for workers with the growth of information technology and logistics. The monotonous work is also a psychological hazardous factor, so the influence of work methods on workers’ health might be multilateral. The work-world is changing, however the physical overload from lifting weights and manual material handling may not disappear in the near future, as the long supply chain necessary for globalized production means that goods are often produced in one country and consumed in another. A calculation method (MODEL) for the assessment of the ergonomics of manual handling of loads is presented in the study. The results of the use of the method are given in manufacturing, for comparison in oldsters’ care hospital, where the physical overload is rather high. Innovations have been introduced in the last years. Musculoskeletal disorders (MSDs) connected with monotonous work are medically examined for garment workers. In parallel, the questionnaire for assessment of mental strain of workers was used. There is no mental strain observed in garment workers, but it is rather high for medical personnel. The results show the possibilities to improve the work environment and workers’ health through ergonomic analysis of workplace, good workplace design, education of special trained occupational hygienists and through them the education of blue-collar workers, the use of robot manipulators and roller conveyors, the increase of management interest and acceptance of ergonomics, the build-up of a bridge between planning and production departments.

계란 등급판정을 위한 파각란 자동 검사 시스템

Egg grading is determined by exterior and interior quality. Among the evaluation methods for the egg quality, a candling method is common to identify eggs with cracked shells and interior defects. But this method is time-consuming and laborious. In addition, practically, it is challenging to detect hairline and micro cracks. In this study, an on-line inspection system based on acoustic resonance frequency analysis was developed to detect hairline cracks on eggshells. A roller conveyor was used to transfer eggs along one lane to the impact position where each of eggs rotated by the roller was excited with an impact device at four different locations on the eggshell equator. The impact device was consisted of a plastic hammer and a rotary solenoid. The acoustic response of the egg to the impact was measured with a small condenser microphone at the same position as the impact device was installed. Two acoustic parameters, correlation coefficient for normalized power spectra and standard deviation of peak resonant frequencies, were used to detect cracked eggs. Intact eggs showed relatively high correlations among the four normalized power spectra and low standard deviations of the four peak resonant frequencies. On the other hand, cracked eggs showed low correlations and high standard deviations as compared to the intact. This method allowed a crack detection rate of 97.6%.

On Abnormal Vibration Generated in Flow Dynamic Conveyor

This paper describes a self-excited vibration of a Flow Dynamic Conveyor (FDC). The FDC is often used in power plants and in iron works because of superiority in noise control compared with a roller type conveyor. The FDC consists of a trough and a belt, and the air is supplied from many holes provided on the trough. A large vibration suddenly occurs when the flow rate becomes the critical value. In this paper, some measurements were performed in order to clarify the phenomenon. As a result, it was found that the phenomenon was the self-excited vibration based on the interference between two vibration systems such as the load·air-spring system and the trough·supporting system.

Specific features of the operations of an induction motor with a squirrel-cage rotor in a frequency-regulation system

Rational systems for the drives of hoisting cranes, roller conveyors, and elevators are solved taking into account specific features of the operation of inductions motors with the squirrel-cage rotor in a frequency regulation system. In addition to saving electric energy (in some cases up to 70%) operational parameters of equipment (accuracy, power efficiency, etc.) are improved, while the cost of investments is decreased.

Technology for the hot rolling of strip after modernization of the laminar-cooling unit on the roller conveyor of the 2500 hot-rolling mill

This article describes the modernization of the laminar cooling system on the 2500 hot-rolling mill at the MMK and its effect on the mechanical characteristics of the finished rolled product. Results are presented from studies of the mechanical characteristics of rolled strip made of tube steel. The distribution of the characteristics over the length strip was determined. The article also shows the dynamics of the change in the number of rolled products of steel 10 that failed to meet the existing specifications in initial tests.

Use of flatness gage IP-4 to check the shape of titanium alloy plates as they move along a roller conveyor

Flatness gage IP-4 scans the surface of a plate as it moves along a roller conveyor. The measurements are made at a frequency that prevents any local convexities or concavities on the surface from going undetected. The flatness criterion used is based on the angles of inclination of elements of the surface relative to the base plane. Comparison of measurements made with the IP-4 on a plate moving along a roller conveyor and static measurements made with an Optel unit showed good visual and statistical agreement between the two sets of results. Repeated measurements made on the same plate immediately after its planishing showed that the shape of the plate changes somewhat during its cooling. However, the information obtained on these changes is not presently reliable enough to serve as a basis for making any corrections to the planishing regime.

Performance parameters of TiN — AlN ceramic end seals frictionally coupled to steel

Performance parameters (friction moment, temperature in the friction zone, and surface roughness parameter Ra) of friction couples 50% TiN + 50% AlN (composite 1 ) steel and 25% TiN + 75% AlN (composite 2 ) used as end seal components of belt conveyor rollers have been determined experimentally.

The effect of a commercial UV disinfection system on the bacterial load of shell eggs

To study the effect of UV irradiation on the bacterial load of shell eggs and of a roller conveyor belt. The natural bacterial load on the eggshell of clean eggs was significantly reduced by a standard UV treatment of 4.7 s; from 4.47 to 3.57 log CFU per eggshell. For very dirty eggs no significant reduction was observed. Eggs inoculated with Escherichia coli and Staphylococcus aureus (4.74 and 4.64 log CFU per eggshell respectively) passed the conveyor belt and were exposed to UV for 4.7 and 18.8 s. The reduction of both inoculated bacteria on the eggshell was comparable and significant for both exposure times (3 and 4 log CFU per eggshell). Escherichia coli was reduced but still detectable on the conveyor rollers. The internal bacterial contamination of eggs filled up with diluent containing E. coli or S. aureus was not influenced by UV irradiation. There is a significant lethal effect of UV irradiation on the bacterial contamination of clean eggshells and recent shell contamination, contamination of rollers can be controlled and the internal contamination of eggs is not reduced. The penetration of UV into organic material appears to be poor and UV disinfection can be used as an alternative for egg washing.

Refinement of Geodetic Measurements in Construction and Operation of Float-Glass Lines with a Continuous Production Cycle

The authors justify the need to use geodetic measurements to detect deformation processes on rotating surfaces of roller conveyors on industrial sheet-glass production lines. The geodetic instruments used for this purpose are described and their principle of action is analyzed.

Capacity analysis of an iron foundry fettling-shop, using virtual manufacturing technology

The concept of virtual manufacturing has been attracting the attention of foundrymen. With this technology simulation models of real production systems can be built in computer based on data, logics, and layout of the systems respectively. The simulation model can help foundry management to analyze the existing production system and they can modify the layout or process route of the model on computer screen when necessary. Then the data will be fed back to show the effects of the modifications before actual modifications are made.This paper gives a brief introduction of virtual manufacturing technology and introduces a simulation model of the fettling shop of a leading iron foundry for engine castings in China. The bottlenecks of the fettling shop with different input levels and product mix have been found by the simulation analysis and the maximum capacity of the existing shop has been calculated with the model. The virtual fettling shop has helped the foundry management in making decision to modify the roller conveyor system.

Investigation of Salmonella contamination and disinfection in farm egg-packing plants.

As part of a field-based study of the distribution and persistence of Salmonella infection on commercial egg-laying farms, sampling was carried out on one or more occasions in egg-packing areas of 12 farms infected with Salm. Enteritidis. Salmonellas were isolated by cultural methods. Contamination was common, with Salmonella being found in 23.1% of floor swab samples, 30.8% of grading tables, 23.1% of conveyor belts or rollers and 23.8% of candlers. Four farms were sampled after cleaning and disinfection of packing plants had been carried out on the previous day, and residual contamination was found on 6.9% of samples from grading tables, 16.0% holding/sorting tables, 12.6% of conveyors or rollers, 16.7% of vacuum egg lifters, 21.4% of floor surfaces and 5.0% of egg store floor surfaces. Sterilized eggs passed through five farm packing plants showed a contamination rate of at least 16/5,948 (0.3%) egg passages. It is apparent that contamination in egg-packing plants may be a significant contributory factor to external contamination of shell eggs, and improved methods of cleaning and disinfecting egg-handling equipment are required. The presence of Salmonella contamination in egg-packing plants presents a contamination hazard for eggs from Salmonella-free flocks. Samples from equipment in the packing plant could also be used for screening for detection of Salmonella in the throughout of the plant.

Vegetable Transport Operations With Horizontal Roller Conveyors

Abstract. The action of horizontal roller conveyors on isolated vegetable products, or mass quantities of product, is examined and related to product orientation and size relative to roller diameter and spacing. An isolated specimen on a roller conveyor typically aligns its long axis with the roller axes and is subsequently not transported across the rollers. Efficient transport occurs only when the conveyor is loaded to a product density that provides contact between two or more product specimens. Roller diameters larger than three times the smallest product dimension are usually inefficient transporters. Roller spacing, or the slot width between rollers, can be varied to provide size grading functions by roller conveyors. Conveyor bed rollers may also be employed as devices to uniformly feed grading or packing line equipment from bulk containers.

An extended scheduling model for producing corrugated boxes

Today, custom and shipping regulations recognize the importance of lightweight and high performance corrugated boxes, and encourage wider usage of them. Usually, the boxes are produced by glueing layers of paper from roll stocks and cutting carton boards in certain sizes in the corrugater machine, drying them in the buffer area, and converting the flat boards into boxes in the converting machines. Similar to previous work, this study also deals with the cutting stock, buffer utilization and machine loading problems. Additionally, it includes set-ups in the converting machines and operating characteristics of roller conveyors in the buffer area. A binary linear program is proposed to maximize the total length of converted paper boards in one shift and to minimize the percentage trim loss. An optimal decomposition algorithm is developed to employ Successive Linear Programming Relaxations until the upper bound on the throughput is reached. An experimental study, with the real data obtained from a local company, indicates that implementable optimal solutions can be efficiently achieved. Furthermore, an approach is proposed for conducting the trade-off studies between the total throughput and the total trim loss.

Stresses, Slip and Abrasion of Rubber Covered Conveyor Rollers

Abstract Conveyors consist of rubber coated, fiber reinforced belts which are supported and driven by rollers. The rollers are generally coated to increase and stabilize the friction and to reduce abrasion, noise and dirt buildup. Pressures and shear stresses in the rubber layer depend on belt tension, driving forces, geometry and material properties of belt and roller. Most rollers fail due to abrasion when the shear stresses are higher than the friction forces. Slip due to pressure between the belt and the rubber layer is proportional to pressure. Additional slip arises from troughing transitions, uneven belts and rollers and from driving forces. Abrasion due to slip is proportional to the pressure of the belt to the power 1.5 to 3. Equations to predict stresses, slip and abrasion are presented. To reduce abrasion rates, conveyors should have large diameter rollers, low belt tension and a wide belt. Also, cylindrically machined pulleys, high quality belts and long troughing transitions should be employed.

Characteristics of a contract electron beam and bremsstrahlung (X-ray) irradiation facility of Radia industry

A contract electron beam(EB) and bremsstrahlung(X-ray) facility with use of NHV 5 MeV, 30 mA Cock-Croft Walton machine is operational for EB since April 1991, and X-ray commercial irradiation was started in 1992 summer. The facility is consisted of the EB machine, bremsstrahlung target, chain and roller conveyor, and automatic turnover machine for dual sided irradiation. The operation of the system is fully controlled by LAN of personal computers for client's order, EB characteristics, beam current control proportional to the conveyor speed, turnover of product in processing mid point, and output of processing record to clients. The control and recording systems avoid human errors. This paper mainly discusses X-ray processing.

Laboratory simulation of the wear process of belt conveyor rollers

Rollers used to support belt conveyors deteriorate as the result of a three-body wear process in which ore particles become trapped between the belt and roller to create abrasive wear under slight stress. Therefore, when a roller blocks as the result of a change in rolling motion, the combined action of the belt and abrasive particles transforms the steel roller into a sharp instrument that can cut the belt. New composite materials that prevent this from happening are currently the subject of experiments in plants and laboratories. The rubber wheel test simulates the type of wear that occurs when the roller is blocked. To correctly simulate the wear of rollers under normal conditions, the rubber wheel test apparatus was modified to allow the sample to turn and thus, more accurately duplicate in situ conditions. In this paper, we compare the wear resistance of a low carbon steel and polyester matrix composites containing hard particles. For all tests, the loss of weight converted into loss of volume was used to determine wear resistance.