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Burr formation in drilling intersecting and cross holes is extremely important in automobile and aerospace industry. Oil inlet holes in shafts is one of the example. The burr formed in this region are of critical in nature due to inaccessibility and three dimensional geometry. In components like crankshafts holes drilled are of intersecting in nature and exit burrs are formed inside, around the periphery. In many production situations drilling intersecting holes occur and variations of the work piece exit angle around the periphery, inclination and curvature at the exit, cause burrs of different geometries. The shape of the burrs around the on-centered holes is more uniform when compared to off-centered holes. Burrs on off-centered holes are unpredictable in nature. Miniature holes (ϕ 3-12mm) are drilled with complex geometries are of intersecting configuration. Burrs in these areas difficult to reach and not accessible. Ordinary methods like hand deburring results in incomplete burr removal and can cause damage during operations. Automotive engine and transmission components are frequently drilled with intersecting holes. These holes act as conduits for lubrication and cooling fluids. Burrs formed in these regions may cause turbulence and even blockage to the flow of liquids and gases. This can be disastrous and cause serious problems during operation. Complex geometry and limited accessibility of these burrs at intersections may become bottleneck in the manufacturing systems. In case parts having several intersecting bore holes, cross holes at the intersection areas, the presence of burr can adversely influence the correct operation of the hydraulic systems. The blocking and detachment of burr can cause catastrophic failures (Bolundut, 2010). The burrs are inaccessible and removing them by unsuitable method can damage the functionality of the components. Removing of these burrs pose challenge to the production engineers especially where many holes intersect with diameter ratios close to unity. Cross holes burrs are termed as potato chip burrs (Jim, 2015) are considered as nagging problems in manufacturing industry. These burrs are located inside the components with blind holes and intersections. Adding to the complexity burrs at angles and off-centers can create partial breakout and irregular edges. It has always been challenging for manufacturing engineers to device a suitable method to deburr these areas. Typical components include hydraulic manifolds, fittings, elbows, cam shafts, crankshafts, connecting rods, large oilfield parts and aerospace, medical, semiconductor components for industrial control applications.
Several researchers have contributed to solve the burr problem by ECD. Choi and Kim (1998), Jain (2002), and Sarkar et al. (2004) have explained deburring using CBN wheels, graphite balls with different electrolytes. Ghabrial and Ebeid (1981) have explained the electrolytic methods for deburring. ECD is applicable to stainless steels and was investigated by Shome et al. (2008). Xu et al. (2010) developed mathematical model with deburring time and burr height as variables. Pulse electrochemical deburring through a mathematical model is described by Ning et al. (2011). Kun Wang et al. (2016) proposed gelatinous electrolyte for ECD and to prevent stray corrosion. Without macroscopic liquid flow, this electrolyte restricts the area of deburring to the narrow region around the burr. Results here showed that original precision and surface quality is maintained which is not possible in conventional electrochemical deburring process. Xinghua Zheng et al. (2013) used the process of ECD to remove intersecting hole burrs and stainless-steel pipe inner wall burrs. Through experimentation, influence of process parameters like process time, electrolytic composition, and concentration on quality of deburring is explored. Here copper electrode is used, and quality of deburring is evaluated from concentration and deburring time point of view. Zefei Wei et al. (2013) established a mathematical model based on FE model with current density as the variable. Resulting expressions for time of deburring is recorded. Both theoretical and experimental verifications are carried out using brass tool on final bur height variations. Eun Sang Lee et al. (2012) investigated the deburring of microburrs on Magnesium alloy. The experimental conditions are studied and evaluated are electrolyte and its composition, applied currents, duty factors, and inter electrode gap.