Dust Collection Validity and Effect of Hole Shape Accuracy of CFRP with Developed Hollow-Type Drill and Dust Collector

2016 ◽  
Vol 10 (3) ◽  
pp. 324-333 ◽  
Author(s):  
Masahiro Hagino ◽  
◽  
Takashi Inoue ◽  
Masanobu Mizoguchi ◽  
Wataru Aoki ◽  
...  
Keyword(s):  
Health And Safety ◽  
Machining Accuracy ◽  
Dust Collector ◽  
Dust Collection ◽  
Shape Accuracy ◽  
Collection Rate ◽  
Hole Shape ◽  
Spindle Unit ◽  
Reinforced Plastic ◽  
Boring Hole

The drilling of carbon fiber-reinforced plastic (CFRP) has many important aspects, such as collecting the fine cutting chips. Serious problems relating to machining accuracy can arise when the fine cutting chips diffused into the air are deposited or mixed in the sliding surface and spindle unit of a machine tool. Moreover, the environmental aspects of fine cutting chips can seriously affect the health and safety of workers. Our group has developed a new hollow-type drilling device with a cyclone-type dust collection system, which aspirates and ejects fine cutting chips from a penetration hole in the central part of the drill shank to outside the cutting area. We produced the tools with drills both without a point angle for the counter-boring hole processing and with a point angle for general drilling. In this study the effect of the dust collection rate for cutting chip and the drilling hole shape accuracy are evaluated for the hollow-type drill with two different cutting edge shapes. The results demonstrate the possibility of suppressing the occurrence of fine cutting chips when the hollow-type drill edge is similar to the shape of general twist drill edges. The hole-finish surface properties were improved, and we obtained a higher dust collection rate.

scholarly journals Application and Research of Swirling Curtain Dust Collection Technology in Mines

2020 ◽  
Vol 10 (6) ◽  
pp. 2005 ◽  
Author(s):  
Gang Li ◽  
Jinhua Hu ◽  
Xiaoli Hao ◽  
Huaidi Qu
Keyword(s):  
Health And Safety ◽  
Dust Removal ◽  
Water Volume ◽  
Dust Collector ◽  
Potential Hazard ◽  
Dust Collection ◽  
Metal Mine ◽  
Transfer Station ◽  
Air Speed ◽  
Low Efficiency

During the production process in mines, large amounts of dusts are produced. The dusts pose a potential hazard to the health and safety of miners. Traditional dust removal methods, such as ventilation, water sprays and foam technology, cannot completely solve the problem of dust pollution, due to low efficiency or high consumption of water or large resistance (>2000 Pa). Therefore, a swirling curtain dust collector (SCDC) was proposed to collect the dust in mines. The device was combined swirling atomization with spray curtain for dust removal. The performance of SCDC was investigated. According to the results, the optimum working condition of the device was: air pressure: 0.35 MPa, water volume: 30 L/h; liquid–gas ratio: 0.15 L/m3; air speed: 14–16 m/s. Under these operation parameters, the suppression efficiency of total dust and respirable dust were over 99.8% and 97%. The proposed device was applied at transfer stations of Luohe Metal Mine in Anhui, China. The application results showed that the dust concentration at the outlet of SCDC in the transfer station is lower than 20 mg/m3, which is stipulated by Chinese standard GB 28661-2012. The proposed device is expected to replace the traditional Venturi wet scrubber in mines.

scholarly journals Design and Optimum of Dust Collector with Corrugated Plate for Underground Mine

2018 ◽  
Vol 2018 ◽  
pp. 1-5
Author(s):  
Ming Li ◽  
Chao Wu ◽  
Zhi-yong Zhou ◽  
Wei-chun Lian ◽  
Zhi-xiong Chen
Keyword(s):  
Removal Efficiency ◽  
Three Dimensional ◽  
Surface Characteristics ◽  
Dust Removal ◽  
Dust Collector ◽  
Dust Collection ◽  
Ansys Fluent ◽  
Metal Mine ◽  
Lead Zinc ◽  
Dimensional Simulation

A set of dust collectors was designed with corrugated plate for an underground metal mine, which has low ventilation resistance, simple maintenance, and strong environmental adaptability. A three-dimensional simulation model was built based on ANSYS-Fluent software, and it was used to analyze the influence law of key parameters on the comprehensive dust removal efficiency; the angle of corrugated plate to the horizontal plane, the surface characteristics of plate, pressure loss and dust removal efficiency were discussed. The optimal design scheme of the dust collector was determined according to the simulation results. The dust collection was carried out in the Fankou lead-zinc underground metal mine in China, and the total dust removal efficiency was more than 95%, and for respiratory dust, it was more than 85%. This dust collector can be widely used in similar underground metal mines.

On-Machine Profile Measurement of Arc Grinding Wheel in 3-Axis Machine Using Non-Contact Displacement Sensor

2010 ◽  
Vol 37-38 ◽  
pp. 773-782
Author(s):  
Hao Huang ◽  
Xiang Yang Lei ◽  
Qiao Xu ◽  
Yin Biao Guo ◽  
Wei Luo
Keyword(s):  
Measurement Data ◽  
Measuring Method ◽  
Grit Size ◽  
Displacement Sensor ◽  
Grinding Wheel ◽  
Machining Accuracy ◽  
Profile Measurement ◽  
Shape Accuracy ◽  
Wheel Profile ◽  
Contact Displacement

Grinding is a processing method that involves duplicating shape accuracy, so the shape accuracy of the grinding wheel plays a crucial role in machining accuracy. However, this accuracy is difficult to obtain. This paper describes an on-machine wheel profile measuring method that uses a non-contact displacement sensor to obtain the shape accuracy of an arc grinding wheel in a 3-axis aspheric surface grinding machine. This method involves data processing with object radius confined filtering, as well as evaluation using the methods of fitting residual error, measurement uncertainty, and machining result simulation. To verify the feasibility of this measuring method, experiments were performed using two diamond grinding wheels (FEPA D91 with grit size 75-90 μm, and FEPA D15 with grit size 10-25 μm). The experimental results indicate that the method is accurate enough to give the arc grinding wheel profile measurement, while the measuring uncertainty is of the same order of magnitude as the grit size (that is, tens of μm). Moreover, the simulation of the grinding effect with wheel profile measurement data can derive the relationship between the wheel profile error and the machining form error, and can be used to instruct the truing time determination for precision grinding.

scholarly journals Dust emissions’ reduction into the atmosphere by environmental-engineering systems of smallsize devices with counter-swirling flows (CSF)

2019 ◽  
Vol 138 ◽  
pp. 01037
Author(s):  
N.M. Sergina ◽  
A.A. Sakharova ◽  
V.N. Azarov ◽  
D.V. Azarov ◽  
M.A. Nikolenko
Keyword(s):  
Collection Efficiency ◽  
Swirling Flows ◽  
Environmental Engineering ◽  
Emissions Reduction ◽  
Dust Collector ◽  
Engineering Systems ◽  
Collection System ◽  
Dust Collection ◽  
Dust Emissions ◽  
Dust Collection Efficiency

The article discusses the features of using environmentalengineering systems of small-size devices with counter-swirling flows (CSF) to reduce dust emissions into the atmosphere. The reasons for the decrease of the dust collection efficiency by CSF systems are analyzed. The layout diagram of the dust collection system with CSF devices and the organization of suction from the dust collector hopper are given.

Influences of Processing Parameters on Hole Shape Accuracy in Drilling Carbon Fiber Reinforced Composite

2011 ◽  
Vol 325 ◽  
pp. 375-380 ◽  
Author(s):  
Gui Yu Li ◽  
Jian Feng Li ◽  
Jie Sun
Keyword(s):  
Production Efficiency ◽  
Processing Parameters ◽  
Frequency Domain Analysis ◽  
Defect Production ◽  
Shape Deviation ◽  
Shape Accuracy ◽  
Hole Shape ◽  
Reinforced Composite ◽  
Drilling Parameters ◽  
The Relationship

Drilling parameters have great influences on hole accuracy and defect production. In this study, single factor test is applied to obtain the relationship between the torque deviation and the spindle speed n at different feeds per revolution fr. White Light Interferometer (WLI) is applied to measure the hole shape. Based on the frequency domain analysis of torque deviation, the cause of hole shape deviation is investigated. Relationship between the hole shape accuracy and drilling parameters is established, which can be used to predict the hole shape by analyzing the torque deviation. Moreover, the reasonable processing parameters can be selected to obtain drilling hole with ideal shape and satisfying production efficiency.

Ultra-precision grinding of asymmetric curved surfaces by line contact with cup wheel

2012 ◽  
Vol 227 (1) ◽  
pp. 111-119 ◽  
Author(s):  
Guang Feng ◽  
Fengwei Huo ◽  
Dongming Guo ◽  
Renke Kang ◽  
Zhuji Jin
Keyword(s):  
High Surface ◽  
Work Piece ◽  
Machining Accuracy ◽  
Curved Surfaces ◽  
Line Contact ◽  
Wheel Wear ◽  
Shape Accuracy ◽  
High Surface Quality ◽  
Novel Approach ◽  
Cup Wheel

The wheel wear is a crucial factor affecting the shape accuracy while grinding the asymmetric curved surface components. To decrease the effects of the wheel wear and improve the machining accuracy, a novel approach of grinding with large-size and fine-grained cup wheel was suggested. This method has many advantages: a full line contact of the cup wheel against the work-piece can be realized, the wheel shape can be well maintained, and the wheel wear is uniform and can be compensated just by feeding along its axis. Moreover, a mathematical model was developed to analyze the grinding motion and the grinding principle deviation. Two hydrodynamic seal rings with wavy surfaces used in reactor coolant pumps were taken as examples to verify the practicability. It is expected to be an efficient method to manufacture more complex asymmetric curved surfaces with high shape accuracy and high surface quality.

scholarly journals Study of dust collection effectiveness in cyclonic-vortex action apparatus

2021 ◽  
Vol 1 (3(57)) ◽  
pp. 21-25
Author(s):  
Andrei Torsky ◽  
Alexander Volnenko ◽  
Leonid Plyatsuk ◽  
Larysa Hurets ◽  
Daulet Zhumadullayev ◽  
...  
Keyword(s):  
Turbulent Diffusion ◽  
Particle Deposition ◽  
High Efficiency ◽  
Collection Efficiency ◽  
Dust Collector ◽  
Fine Dust ◽  
Dust Collection ◽  
Contact Stage ◽  
Fractional Efficiency ◽  
Overall Efficiency

The object of research is the efficiency of dust collection of fine dust in an apparatus with an intense turbulent mode of phase interaction. One of the most problematic areas of the existing dust and gas cleaning equipment is the low efficiency of collecting fine dust. Effective cleaning of exhaust gases from dust involves the use of multi-stage cleaning systems, including wet and dry dust cleaning devices, which entails high capital and operating costs. These disadvantages are eliminated in the developed design of the cyclone-vortex dust collector with two contact zones. The device implements both dry and wet dust collection mechanisms, which allows for high efficiency of dust removal at high productivity. The conducted studies of the total and fractional efficiency of dust collection when changing the operating parameters of the developed device showed that the efficiency of collecting fine dust is 98–99 %. The increase in the efficiency of dust collection in the dry stage of the device is due to an increase in centrifugal force. In the wet stage of contact, the efficiency reaches its maximum values due to the vortex crushing of the liquid in the nozzle zone of the apparatus. Studies of the fractional efficiency of the apparatus show that with an increase in the diameter of the captured particles, the efficiency of the dust collection process for dry and wet stages, as well as the overall efficiency, increases. With an increase in the density of irrigation, the overall efficiency of dust collection in the apparatus increases. It has been established that an increase in the efficiency of capturing highly dispersed particles occurs due to turbulent diffusion, the value of which is determined by the frequency of turbulent pulsations and the degree of entrainment of particles during the pulsating motion of packed bodies. To describe the results obtained, a centrifugal-inertial model for a dry contact stage and a turbulent-diffusion model of solid particle deposition for a wet contact stage are proposed, which make it possible to calculate the dust collection efficiency of the contact stages, as well as the overall efficiency of the cyclone-vortex apparatus. The results obtained show the prospects of using devices of this design at heat power plants and other industries.

scholarly journals Study on the Stiffness, Longevity and Reliability of the Spindle Unit of Eclipse 300 CNC Lathe with Different External Load

2021 ◽  
Vol 31.2 (149) ◽  
pp. 58-64
Keyword(s):  
Machine Tools ◽  
Spindle Assembly ◽  
Machining Accuracy ◽  
Initial Stiffness ◽  
Spindle Unit ◽  
Cnc Lathe ◽  
The Relationship ◽  
External Loads ◽  
Remaining Time

The stiffness of the spindle assembly of machine tools in general and also CNC machines in particular is an important criteria to evaluate the quality of machining. The initial stiffness of the spindle assembly is due to pre-load. During operating, the spindle assembly is wear under the influence of external loads including cutting force and speed. It reduces the stiffness of the spindle assembly, as well as decreasing machining accuracy. This study presents the results of various stiffness of the spindle assembly under external loads in laboratory conditions. Based on the relationship between the stiffness and the amount of axial wear of the spindle assembly according to the working time, as well as the permissible stiffness limit to predict remaining time, reliability and time of adjusting the pre-load to maintain stability and machining accuracy.

Atomistic Simulation and Experimental Investigation of Ultra Precision Cutting Processes

1999 ◽  
Vol 578 ◽  
Author(s):  
R. Rentsch
Keyword(s):  
Process Development ◽  
Semiconductor Industry ◽  
Cutting Process ◽  
Effective Control ◽  
Machining Accuracy ◽  
Process Data ◽  
Shape Accuracy ◽  
Ultra Precision ◽  
Precision Machine Tools ◽  
Cutting Processes

AbstractTypical applications for components and equipment with extreme quality requirements regarding surface roughness, shape accuracy and integrity of the generated surface structure can be found in optical and semiconductor industry. Ultra precision machine tools equipped with sharp, single crystalline diamond provide the necessary machining accuracy. Here the actual cutting process can take place at atomic level, which makes the acquisition of typical cutting process data difficult or impossible. However a detailed characterization and understanding of the process is vital for its effective control as well as for further tool and process development.Therefore an approach is made that focuses on linking results from atomistic simulations with results and observations from cutting experiments. In this work the potential of molecular dynamics (MD) modeling for studying phenomena related to ultra precision cutting processes will be demonstrated. Observations and first results for machining copper will be presented.

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