D. Nageswara Rao

Influence of emulsifier content on cutting fluid properties

Abstract The use of cutting fluids has been well recognized for centuries. To cater for the needs of state-of-the-art machining processes, several fluid formulations are available in the present-day market. Of the available fluids, water-soluble fluids occupy a role of prominence. Although the need for cutting fluids has been well emphasized and much explored, the role of the different ingredients of the fluid has not been much investigated. The present work is an attempt to study the role of emulsifier content on the properties of cutting fluid.

Integration of CAD/CAM/CAE in Product Development System Using STEP/XML:

Everyday the companies make strategic business decisions to improve their position in the market. They examine the business value chain to improve the product innovation, customer intimacy, and operational efficiency. Product development is one of the key weapons in the war for a competitive advantage. Policy in product development is in the form of five ‘rights’, viz. the right information, in the right format, for the right people, in the right location, and at the right time. The design and development of the product in small-scale and large-scale industries are managed with CAD/CAM/CAE systems. All the systems are heterogeneous. The Standard for the Exchange of Product (STEP) model data [1] is used as the standard format for models created in the CAD/CAM/CAE systems. In this research, an interface program to communicate the product data in the client/server environment has been developed. The interface program converts the STEP file into an XML file. The XML format is the lightweight web-based communication format. With a properly secured web page communication for different users in the enterprise, the authors achieve the concurrent engineering environment throughout the product life cycle

Solid lubricants in machining

This article presents a review of solid lubricants application in different machining processes such as grinding, milling, drilling, and turning. Of late, several reasons have led to the increased usage of solid lubricants in machining. The heat generated in the cutting zone during machining is critical in deciding the workpiece quality. Although cutting fluids are widely employed to carry away the heat in machining, their usage poses threat to ecology and the health of workers. Hence, there arises a need to identify eco-friendly and user-friendly alternatives to conventional cutting fluids. Modern tribology has facilitated the use of solid lubricants as an alternative to cutting fluids in machining. Graphite, calcium fluoride, molybdenum disulphide, and boric acid are the general solid lubricants used in machining. Process performance is improved with the application of solid lubricants in machining. By reducing coefficient of friction, cutting forces and tool wear are reduced in machining with solid lubricants. Reduction in cutting forces results in lower specific energy requirement and thus reduces production cost. Surface quality of the machined workpiece is also improved with solid lubricants.

Prediction of Weld Bead Geometry in Plasma Arc Welding using Factorial Design Approach

The effect of various process parameters like welding current, torch height, welding speed and plasma gas flow rate on front melting width, back melting width and weld reinforcement of plasma arc welding on aluminum alloy is investigated by using factorial design approach. Variable polarity plasma arc welding is used for welding aluminum alloy. Trail experiments are conducted and the limits of the input process parameters are decided. Two levels and four input process parameters are chosen and experiments are conducted as per typical design matrix considering full factorial design. Total sixteen experiments are conducted and output responses are measured. The coefficients are calculated by using regression analysis and the mathematical models are constructed. By using the mathematical models the main and interaction effect of various process parameters on weld quality is studied.

Influence of emulsifier content on properties and durability of cutting fluids

The use of cutting fluids is well recognized for several years. To cater the needs of state- of- art machining processes, several fluid formulations are available in the present day market. Of such available fluids, water-soluble fluids are dominant. Though, the need of cutting fluids is explored, the functionality of different ingredients of the fluid is not much investigated. The present work is an attempt to study the role of emulsifier on the properties and performance of cutting fluid. In the present part of the paper, estimation of basic properties and microbial contamination of the fluids with varying emulsifier contents is dealt.

Surface model and tool-wear prediction model for solid lubricant-assisted turning

Mathematical models for surface roughness and tool wear are developed through regression analysis of the experimental data collected from machining. Different particle sizes and flowrates of solid lubricants are employed in the study. Experimental results show a significant effect of solid lubricant particle size and flowrate on surface roughness and tool wear. Decrease in the particle size resulted in reduced tool wear and surface finish improvement. Various machining parameters such as cutting forces, tool wear, and surface roughness improved with an increase in the flowrate of solid lubricant up to a certain level and remained constant at higher flowrates. To estimate the effect of solid lubricants on machining, exponential models are proposed in the present work to predict tool wear and surface roughness as a function of solid lubricant particle size, flowrate, machining time, and cutting force. Predicted values obtained from the developed model and experimental results are compared, and error<10 per cent is observed.

Implementation of interactive database system for STEP-geometric data from EXPRESS entities

Today information systems have become the key factor of current computer based engineering applications. So database are designed to support data storage, processing, and retrieval activities related to data management, and they are the key to implementing engineering information models. However, the current mainstream databases are mainly used for business applications, some new engineering requirements challenge todays database technologies and promote their evolvement. The main focus of this paper is to determining the requirements of a database for STEP-Geometry entities that supports integrity validation of versioned design artifacts through effective management of evolving constraints. In this paper develop a tool for separate and store the geometric data from STEP file using EXPRESS entities. Finally this tool operates around a version model that uses a well-defined configuration management strategy to manage and storage of geometric data.

A network model for material handling with split loads using AGVS in machine modules

The automatic guided vehicle system (AGVs) is an important element for material handling facility in the computer integrated manufacturing. The essential capability of an AGV is the ability to transfer loads to remote locations or through complex paths under computer control. They are used to move jobs between work stations on a factory floor. Research in this area is directed towards the development of a path layout design and routing algorithms for vehicle movement and control. The problem is to design a path layout and a routing algorithm minimising the distance travelled by AGVs considering sufficient but necessary conditions. Split loads concept is implemented for material handling for effective utilisation of AGVs. The capacity utilisation is analysed in terms of the distance travelled and the time required for AGVs to complete all pickup and drop-off jobs. Numerical results are presented to compare performance of the proposed model.