Investigation of Drilling Process Parameters of Palmyra Based Composite

The drilling process is the most essential in the final assembly of the mechanical parts. Natural fiber based composites replace traditional materials due to their advantages, such as strength to weight ratio, availability, and environmental hazards. In this work, an attempt has been made to find the minimum thrust force produced by the drill tool at specified drilling process parameters. The drilling process parameters used for the investigation are rotational speed, tool feed, and resins. The spindle speed and feed rate are selected with three levels. Three resin materials were used, namely, epoxy, polyester, and vinyl ester. Taguchi’s L27 orthogonal array was implemented. The result shows that the candlestick drill bit generated lesser thrust force at the specified drilling process parameters, followed by the twist and step cone drill bits.

Experimental Study on the Insulation Layer Thickness of a Novel Ice Coring Device in Loose Sandstone-Type Uranium Deposits

The target strata of sandstone-type uranium deposits are usually located in the fragile and loose strata, which makes it difficult to obtain core samples; consequently, a novel ice coring device for loose sandstone-type uranium deposits is proposed to solve this problem. Experiments proved that the artificial sample can replace the natural sample, and the coring method has high reliability. Ensuring the allegro formation of an ice valve with a given cold source is critical for this coring system, and reducing the loss of cold energy with help of insulation layer is one of the methods to speed up the formation of ice valve. Since the diameter of the drill tool is limited by its working scenario, the thickness of insulation layer is limited to ensure the size of core. Therefore, this paper conducted laboratory experiments of the insulation layer with different thicknesses to study the effect of the insulation layer on the formation of the sand–ice valve. Results show that the insulation layer can reduce the loss of cold energy during the freezing process and significantly affect the formation time of the sand–ice valve. When the thickness of the aerogel insulation layer is 2 mm, the freezing time is 44% shorter than that without insulation layer. According to the tests, the novel ice coring device is expected to solve the coring problem in loose sandstone-type uranium deposits.

INFLUENCE OF PROCESS PARAMETERS IN FRICTION DRILLING OF TITANIUM TI-6AL-4V ALLOY

Friction drilling is a process of using the friction between the rotating conical tool and the workpiece to generate heat and deform the work piece’s material and penetrate the hole. The softened material is pushed sideward and downward to make the bushing. This paper aimed to study the influence of friction drilling parameters. Thrust forces and torque forces were analysed. Experiments were carried out with a friction drill tool made of tungsten carbide on titanium grade Ti-6Al-4V. The parameters used in this study were spindle speed and feed rate. It was found that the thrust force and torque decreased with increased spindle speed and with decrease of feed parameters. The microstructure reveals that deformed grains at hole’s surface relate to hardness on the cross-section of workpiece. The highest value of microhardness was 813.2 HV and reduced to the original hardness of the matrix material.

Hole geometry and surface integrity assessment in drilling of inconel 718 using laser texture filled solid lubricant tools

Purpose Inconel 718 is used in gas turbine engines for aerospace applications due to high creep resistance but generating a hole with good surface integrity is challenging because the γ′′ interface is very strong so that slip is difficult in the grain boundary. So, the purpose of this work is to enhance the performance of drilling using a micro texture drill tool filled with solid lubricant. Design/methodology/approach Three different micro textures such as star shaped with 6-sharp apex, rectangular slots parallel and perpendicular to drill axis are created using laser on the drill tool. Deep cryogenic treatment is done on the textured tool to improve the strength and wear resistance before it is filled with solid lubricant. A detailed experimental investigation is performed to analyse the hole geometry and surface integrity of the drilled hole. Findings The accuracy of the drilled holes is enhanced in the star shaped texture drill tool over other textured and non-textured tools. A significant improvement in surface finish and hardness are observed and moreover cylindricity error, burr height of the hole is less for the above condition. It is also inferred that, at lower feed rate and higher speed produce hole with an accuracy of 96%. Originality/value Aerospace industry is focussing on improving the hole geometry and surface in Inconel 718. This work demonstrates the novel technique to improve drilling of Inconel 718 using laser textured tool filled by the solid lubricant.

Effect of Mass Variation on Vibration Properties of the Tooth in Drilling Operation

Dental cavity represent one of the widespread illness of the tooth. Method for treating of the tooth is to drill the cavity and to fill the hole with suitable material. Measurements show that during drilling the tooth vibrates with increasing mass that causes unpleasant feeling for patient. The aim of the paper is to give the theoretical explanation for this phenomena and to give suggestion for vibration elimination. During drilling, mass of the tooth is decreasing and the so called ‘reactive force’ occurs. Drilling and reactive force cause tooth vibration. The system is modeled as a nonlinear time variable system. An analytical procedure for solving of the equation of vibration is developed. The solution is assumed in the form of the generalized trigonometric function with time variable amplitude and phase. It is obtained that not only the amplitude but also the frequency of tooth vibration in drilling are increased. In addition to reactive force the drilling velocity, diameter of the drill tool and spindle speed affect the vibration level. The appropriate values of these parameters would eliminate or decrease the patient bad feeling.

EVALUASI KESESUAIAN LAHAN UNTUK TANAMAN KACANG TANAH DI KELURAHAN PARDAMEAN KECAMATAN RANTAU SELATAN

Land evaluation is useful as a basis for sector development in an area that is useful for reorganizing existing land use so as to assist in making land use planning decisions. Peanuts have great potential to be cultivated and developed commercially because they have wide adaptability, high productivity, are resistant to plant pests, and are more resistant to marginal conditions. This research is descriptive with survey methods. The sampling method used is based on land map units with a free grid system for data. climates classified by climate type Schmidt and Ferguson. The land evaluation was carried out using the matching method by matching and comparing land characteristics with land suitability class criteria so that to obtain land suitability classes for peanut plants in Rantau Selatan District, Labuhanbatu Regency, there were 6 sample points so that the determination of soil characteristics values for soil samples was carried out using a soil drill tool. at a depth of 0-60 cm. Research results for peanut plants in Pardamean Village, Rantau Selatan District according to marginal / S3. Land suitability for peanut plants cultivated in Rantau Selatan District Labuhanbatu Regency 2.017 ha. The actual land suitability class for peanut plants is Nwa, while the potential land suitability class is S2tcwa.Keywords: Land Evaluation, Peanut Plants, Rantau Selatan, Labuhanbatu