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This paper discusses the cutting temperature and cutting force in end milling difficult-to-cut materials cooled with several types of mists and low-temperature air. The cutting tool was a throwaway end mill with a carbide tip coated with titanium aluminum nitride. The Ti-6Al-4V titanium alloy and AISI D2 hardened steel were used as workpieces. The tool flank temperature and cutting force were measured simultaneously during side milling. The temperature was measured using a two-color pyrometer with an optical fiber. Oil mist and water mist from a mist generator were supplied to the cutting point along with cold air at approximately -27 °C. Compared with dry cutting, the cooling effects of supplying an oil mist and/or cold air were less than for other supply conditions in titanium alloy cutting. However, when water mist was added, the tool flank temperature clearly decreased. The cutting force increased for cases that included water mist. The adhesion of the titanium alloy to the cutting edge of the worn tool was significantly suppressed by supplying water and oil mist with cold air. Tool flank wear also decreased under those lubrication conditions.

Minimum quantity lubrication (MQL) or as it’s called semi dry cutting is a technique which spray a small value of lubricant flow rate to the cutting zone area. MQL has been used in many machining process with different cutting tools and workpiece materials due to its green environments and economically advantageous. MQL has become an attractive option to dry and flood cutting in terms of reduce the temperature in the cutting zone and reduce the cost of the product. However, in MQL seems to be machining limited by cutting temperature, because at high speed the effect of oil mist becomes evaporated. Therefore another alternative cooling approach was used with oil mist in this research. This research presents study the performance of nitrogen gas as a coolant and oil mist as lubricant in turning of hardened stainless tool steel (STAVAX ESR) with hardness 48 HRC. Using a gas as coolant with oil mist is a new solution for enhancing machinability. Turning experiments are carried out on CNC turning machine. The cutting insert grade is KC5010 (PVD-TiAlN wiper coated carbide). The experimental results were: 1) nitrogen gas with oil mist prolongs tool life compare with air with oil mist. 2) better product surface finish by using nitrogen gas with oil mist.

Conventional coolant/lubricants have some drawbacks such as high cost, pollution, and unsatisfactory product quality. New cooling approach by using gases to enhance machinability has been investigated. This study presents the finding of nitrogen gas and nitrogen-oil-mist as conditions when turning of hardened stainless tool steel (STAVAX ESR) with hardness 48 HRC. Turning experiments were carried out on CNC turning machine using rhomboid type wiper coated carbide cutting inserts. The result show that better product surface finish and longer tool life, as well as decrease cutting temperatures could be achieved by using nitrogen-oil-mist condition compared to nitrogen gas condition.

In order to well lubricate the industrial machine and decrease the consumption of lubricating oil, it is necessary to develop a system to monitor and control the density of oil mist. This paper introduces such a system based on LPC2214 of ARM7. The system can monitor 10 parameters, give an alarm to the status of factors which affect the quality of the oil mist and store the relative information into high capacity SD card through I2C bus and SPI bus. All the status information can be shown on LCD so that the operator can realize the system in real-time. System supplies input interface which can set some parameters and display other information on LCD, including history status information of system.Keywords: LPC2214, Oil mist, SD card, LCD

In the present research, a model of the cryogenic oil mist flow field of milling cutters with different interior oil channels was conducted to determine the effects of rotational speed, temperature and flow of cold air. For the milling cutters with single direct hole and double direct holes, the increase of the rotational speed has little effect on the velocity and temperature of the measuring points at different distances along the milling cutters. For the milling cutter with double direct holes the separated streamlines of double direct holes are nearer with the rise of the distance because of the viscidity of cutting fluid. When the distance exceeds 5mm, the separated streamlines combine with each other. For the milling cutter with double helical holes the streamlines of cold air present irregularly. At last, some of the simulated results were validated.

For a long time, the monitor and maintain of navy Vessels equipment is based on the traditional maintain theories and plan maintain. But with the development of electronically and digitization, this kind of traditional mode is more and more hard to satisfy the need of equipment, and restrict the formation and exaltation of troops fighting strength. Currently the technologies of fault prognostics and integrated health management are becoming regarded, especially on many Vessels equipment systems. There are many factors that influence the equipment environment safety, and Oil mist concentration is one of the important factors. So it is very critical to monitor oil mist concentration accurately and quickly. The paper designed a method to carry on the sampling of the air and get the original data. And forecasting the variety of oil mist concentration with grey model, it opens the air decontamination device before attaining the limited value. The calculation shows that the mode is effective, convenient, and has upper fitting precision.

There are many factors that influence the equippment environment safety, and Oil mist concentration is one of the important factors. So it is very critical to monitor oil mist concentration accurately and quickly. A kind of monitor device is designed to carry on the sampling of the air and get the original data. And forecasting the variety of oil mist concentration with grey model, it opens the air decontamination device before attaining the limited value. The calculation shows that the monitor device based on grey theory is effective, convenient, and has upper fitting precision.

An investigation of the cryogenic oil mist flow field of nozzle was carried out in this study. A domain of the nozzle jet area was modeled with Pro/ENGINEER. CFD (Computational Fluid Dynamics) analysis was used to state the velocity field of different distances from the outlet of nozzle. The simulating velocity field was verified with the experimental results. Experimental results on velocity were measured by SYT-2000 digital multipurpose wind speed gage. The orthogonal experiment was designed to investigate the main effects parameters on velocity and temperature. It indicates that higher flow of cold air and smaller diameter of nozzle’s outlet will generate higher velocity. The temperature of cold air has most influence on the temperature of measuring point. Finally the optimum structure of the spraying nozzle was proposed.

A lot of lubricating oil is consumed in the process of the cold rolling of stainless steel. The oil recovery is very important due to some reasons, such as the cost of production and environmental pollution. A set of lubricating oil recovery system is designed and constructed, which is equipped with a set of expanded size recovery oil pan for recycling splashed oil, a high efficiency two-level mist recovery system for recycling the oil mist, and an oil collection platform for recycling the oil rolled. The system is effectively to recovery more of lubricating oil through actual use and measurement.

Minimum quantity lubrication (MQL) is a new cooling technology used in machining process, which is friendly to environment and lower cost. This paper applied computational fluid dynamics (CFD) to analyze flow field of MQL in thread turning. Comprehensively applying droplet breakup method and capillary method, flow field of MQL in cutting zone were analyzed in detail. The results showed that oil mist could enter into cutting zone from sides of chip. And two vortexes existed around cutting zone which could reduce cutting temperature by accelerating heat exchange. Furthermore, flow rate of compressed air had great influence on velocity and diameter of droplets, velocity and pressure distribution of flow field. The effects of different flow rates indicated the larger flow rate was benefit for entering into cutting zone of oil mist.

Stricter environmental regulations are making the use of an ample amount of conventional coolant impossible because of its negative impact on the environment. Consequently, the use of minimum quantity lubrication (MQL) has been regarded as an promising alternative to conventional fluid coolant applications. Despite several studies, there have been a few investigations about the influence of the MQL nozzle position, such as distance from tool-workpiece contact zone, elevation angles, the included angle between jet direction and feed direction. The current study presents experimental investigations on influences of the above parameters on performance in end milling. Tool wear and surface roughness are experimentally studied to compare the effects of different positions. The results show that the setting location of the nozzle is an important factor regarding the effective application of MQL oil mist.

Based on the theory of Fluid Dynamics CFD and Fluid analysis software Fluent，we accomplished the flow field simulation of internal speed and internal pressure of pneumatic oil mist atomizer. Both the flow field simulation and the results of experiment are in good agreement，particle size and density of oil mist change very little when the pressure of compressed air is kept constant while the distance of nozzle and baffle is varied. When the distance from nozzle to baffle is fixed, and the pressure of compressed air is increased gradually, the density of oil mist will increase and the particle size of oil mist will decrease along with the increasing pressure of compressed air. This decreasing trend of particle size of oil mist will slow down when the pressure of compressed air increases to 0.35Mpa. The particle size of oil mist can reach 2μm.

Based on control equations in fluid dynamics, the main thought of oil mist process for cold heading machine is proposed according to the idea of green manufacturing. The computation fluid dynamics (CFD) software is applied to simulate the multi-phase oil mist flow in control box. The simulation results give some figures including distribution and stream line path of multi-phase flow of oil mist in the control box. The results show that the inlet position of oil mist effects on its process and three types of control box are compared, from which the best type is obtained.

Oil mist lubrication is currently widely used as a lubrication method now. It has some advantages as follows: low fuel consumption, uniform lubrication and high efficiency. In job site, oil mist condensation occurs in the pipeline, and this will not only reduce the efficiency, but also lead to accidents. Nowadays, CFD numerical simulation software has been widely applied in design, but the research of oil mist condensation in the transmission process based on CFD is very fare. In this paper, to choose the right the working parameters and a reasonable pipeline layout in job site, the oil mist condensation in the pipeline was simulated based on CFD. And it was found that, the diameter of oil mist particle is mainly influenced by temperature, and the best temperature range is made out.

Cold air cutting is a kind of environmetnally friendly cutting technology. The present study investigated the influence of cold air and cold air with oil mist on cutting temperature, cutting force and tool wear in the machining of Cr12 tool steel. For comparision, dry and flood coolant was also used as the cooling/lubrication conditions in the experiments. The findings of the study show that cold air with oil mist was the most effective cooling/lubrication condition in reducing the cutting temperature, cutting force and tool wear during the machining of Cr12 tool steel.

The density of oil mist in this paper is an important factor of oil mist lubrication technology, according to which the effect of lubrication will be known and from which the study on atomization effect will also benefit. In general, the oil mist density of oil mist lubrication system in working condition is 3-12g/ m3 , the median diameter is 1-3 [1], which is difficult to measure with conventional detection methods. The paper takes advantage of optical rotation principle as a measuring method for density of oil mist and achieves a good experimental result.

Large amount of cutting oil consumption is one of the issues for environment. The Minimum Quantity Lubrication (MQL) technique has been applied to the near-dry cutting process. However, MQL technique generates oil mist which is harmful to the working environment and the health of factory workers. In this study, a new lubrication system called Direct Oil Shot Lubrication System (DOS) was developed and applied to milling processes. The performances of DOS technique was evaluated by measuring the floating oil mist and carrying out the cutting tests. The amount of floating oil mist of DOS system was considerably reduced compared to the MQL. The behavior of small oil drops supplied from DOS nozzle to cutting edge was analyzed by means of a high speed video observation, and the optimum setting for DOS was obtained. The experimental result shows developed DOS system realized the smaller density of oil mist floating than the MQL technique while the DOS attained the almost same lubrication effect in milling process as the MQL technique.