Design, development and modelling of ginning clutch fixture for productivity improvement

. Fixture is one of the important part of machining processes which use for enhancing the efficiency of the process. The conventional ginning clutch fixture is positioned with single fuse body on vertical machining centre. During machining, more time is consumed for loading and unloading which resulted high production time and cost. The solution to an industrial challenge of the design and fabrication of fixture is attempted in the present work. SolidWorks software is used for 3D modelling of novel fixture and stress analysis is performed using ANSYS software which determines the maximum stresses and deformation. Based on the ANSYS results, fixture is fabricated and use for further testing. The ginning clutch fixture was tested during production and was found that the efficiency of the production of ginning clutch was increased by 33%.


Introduction
Ginning is the main tool used in gin industries, and its job is to extract the fibre from cotton seeds while maintaining the fiber's inherent qualities.For the purpose of preparing raw or semi finished cotton for the cotton mills, cotton ginning machines are used.By using a cotton ginning machine, mechanically harvested cotton is transformed into a marketable good.Ginning clutch is one of the major components of gin.During the manufacturing of ginning clutch the sequence of process is forging, turning, drilling, milling and slotting.Milling is one of the machining processes during the manufacturing of the ginning clutch which is done on the vertical machining centre (VMC).In the manufacturing industry, a single job (ginning clutch) is machined at the VMC, one at a timewhich requires more loading and unloading time for a work-part.Researchers analysed the design, development and fabrication of fixture using modelling and simulation approaches is presented in Table 1.After studying various processes and understanding different types of processes in depth.It is noticed that cycle time, loading and unloading time, overall machine time, machining parameters are responsible for improving productivity.Therefore, an attempt has been made for redesigning the fixture which hols multi work-parts.

FIXTURE DESIGN PROCESS:
While designing the fixture, the following 3 major factors should be considered such as locators, clamps and supports.It can also improve the stability of the fixture-workpiece system.There is no limitation to thenumber of supporting elements used in fixtures.To took the main idea of making fixtures by taking a general aspect from the previous setup of manufacturing operation (milling) which helpus to understand the major of freedom which has to be restricted.
The design planning of a fixture is based on the data collected of the ginning clutch manufacturedin the industry and which aim to increase productivity.The data which is mainly required as a draftingsheet of the ginning clutch which shows all the dimensions with proper accuracy in Fig 1.

Design and experimentation:
The data of the VMC machine on which ginning clutch is manufactured such as bed of the VMC machine is 550×1000 mm.Tool material was EN8.The design process also included the analysis such as the clamping position, load distribution and material selection, etc.The modelling of the fixture is done using SolidWorks designing software.By using all the data, the following design dimensions of the fixture is presented.= 344 mm While designing fixture there were various restrictions and parameters which were supposed to be kept in mind for failure less designed.After creating and plotting basic ideas of fixture which were supposed to hold four components at a time.So after the changes, baseplate length is 515 mm Which was supposed to hold a pillar of the square dimension of 140 mm and having a thickness of 23mm.The base plate was supposed to hold the various forces acting on the parts resulting in reason forces on the baseplate.Dimension of the baseplate is 200x23 mm.Further going on the pillars which make up the overall height of the component and hold the top plate which directly attached the part to it install.To make a new change to its motion for vertical playing while machining forces come into action.So this pillar plays an important role and has the dimensions of 140 × 140mm.In this work structure, the degree of freedom is equal to 0. To hold the clutch, upper part of the plate designed having a length of345x140x40 mm.To keep a safe distance from clutches, have to provide allowances at each side as wellas from the outer diameters of clutches.SOLIDWORKS software is used to design fixture.Figure 2 shows the final design based decision.Figure 3 shows various views of the fixture.Design analysis: The analysis of the design of the fixture was executed using SolidWorks software.The first analysis which executed was static loading to find out how different types of stresses, strain, and displacement forces can act upon the fixture.Figure 4 is the model information; it is the fixture information that shows us the   Mesh information: Meshing is one of the important factors during the simulation of any engineering drawing.Mesh is the most significant for correctness, convergence, and rapidity of the simulation.Table 3 presents the mesh information.After simulation of the fixture using static loading, stress, strain, and displacement are analysed loading on the fixture.The results of the fixture after stress, strain, and displacement analysis came out successfully and were ready for the dynamic analysis.Figure 6 shows the stress analysis of the fixture.Figure 7 showsthe displacement analysis of the fixture.Figure .8 shows the strain analysis of the fixture.Dynamic loading: After successful results of the static analysis, moved forward toward the dynamic analysis of the fixture.For dynamic analysis, free vibration is considered over the fixture.Fixture is tested, 5 times applying different amplitudes each time.Figure 9 shows the dynamic loading analysis for the first analysis whose amplitude ranges up to 500 hertz.After applying dynamic loading which is free vibration for different amplitudes and frequencies on the fixture it was found that the fixture design was safe and ready to fabricate.Table 4 shows us the mode list of the dynamic loading for different frequencies.Table 5 shows the mass participation of the fixture during various frequencies applied to the fixture in X, Y, and Z, directions.Following design analysis, it is time to create a working model for the fixture and manufacture various fixture parts.The manufacturing processes for the various parts take different paths, but the first process for each component was the same, which was gas cutting.To begin with different parts, the base plate as shown in Fig. 16 was followed by the top plate because it has the most processes attached to it.The components and processes are discussed further below.This plate had its overall required dimensions after the first gas cutting process, and it was held on a machine bed for drilling holes on four corners.After drilling and increasing the hole diameter on the VMC, the plate was ready to use.These pillar plates as shown in Fig. 17 were brought on a drilling machine after being cut to the required dimensions and have a total of four side holes, four of which are peck holes and the remaining two are through holes.Threading is present in the peck holes as well.This middle plate has also gone through the primary process of gas cutting and comes to its dimensions after which it was given for another process of drilling which includes making 4-peck holes and has also gone through the processes of internal threading.After threading the small holes, the plate was held on its length and drilled with the largest drill possible.After drilling process, increased the hole diameter on VMC, and then the plate was ready to use as shown in Fig. 18 Top plate: This plate goes through several machining processes, the first of which is cutting the plate and then making the small holes, which are through holes, to hold the plate with the pillar plates, thus the 4 and through holes.After the pillar holes, the clamping holes are supposed to be made to hold the clamps, so these holes have additional threading in them, totalling 8 threaded holes.These eight holes on each side of four large holes are supposed to keep the clutch in its cavity.Drilling is created and then modified using a milling process as shown in Fig. 19.The fabrication of fixture is presented in Fig. 20.

Results and discussion:
Successfully designed and developed fixture for the ginning clutch is manufactured for productivity enhancement.The basic process applied for the manufacturing of the ginning clutch fixture was to define the parameters for designing the fixture.Modelling of fixture is done through SolidWorks software.Using the ANSYS, fixture is analysed for various stress, strain, and displacement.The results came out to be successful for manufacturing the fixture as shown in Fig. 20 AISI 1020 steel, cold-rolled material is used to manufacture the fixture.The fixture is tested on the VMC machine which used to manufacture ginning clutch on the VMC machine.After testing the fixture for manufacturing four ginning clutches at a time.It is observed that the time required to mill 4 ginning clutch (loading and unloading time) has been decreased.Hence, manufacturing productivity using novel fixture (holding 4 ginning clutch parts at a time) has been increased by 33% compared to conventional fixture.Shop floor industries would be benefited by using muti-part holding novel ginning clutch fixture.

Conclusion:
• The ginning clutch fixture was successfully designed, modelled and simulated by considering various stress, strain loading, and free vibrations.
• The ginning clutch fixture was successfully fabricated.• The ginning clutch fixture was tested during production and found that the efficiency of the production of ginning clutch was increased by 33%.

Fig 2
Fig 2 Final design of the fixture /doi.org/10.1051/e3sconf/202343001288288 430 volumetric properties of the fixture.The volumetric properties of the fixture include the mass, volume and ddensity.The material used during the manufacturing of the fixture is AISI 1020 Steel, cold rolled.1020 steel has a tensile strength of 350MPa.1020's modulus of elasticity is 205 GPa and the shear modulus is 80 GPa.It has good mechanical properties.Such propertiesare highly efficient for the manufacturing of fixtures.1020 steel has high strength which can help the fixture to increase its shelf life.The model information of ginning clutch fixture shown in figure-4 and material properties shown in Table2.

Fig. 5
Fig. 5 Fixed geometry and force components on the fixture

Fig 7 Fig 8
Fig 7 Displacement analysis (Static loading) Fig 10 shows the dynamic loading analysis over the fixture whose amplitude ranges up to 1000 hertz.Fig 11 shows the dynamic loading analysis over the fixture whose amplitude ranges up to 1000 hertz but for different nodes.Fig 12 shows the dynamic loading analysis over the fixture whose amplitude ranges up to 1500 hertz but for different nodes.

Table 3 :
Mesh Information

Table 4 Mode list Table 5 Mass
participation ➢ Fabrication of fixture: