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All students must be constantly aware of the safety hazards associated with the use of machinery and must know all safety precautions to avoid accidents and injuries. Universal milling machine: As in the picture Mill-3, it includes horizontal and vertical milling, and is used in a peripheral and surface milling. Ram: It is the upper part of the grinding machine and is supported by the bracket.
It is a shaft on which the cutting tools are held by collets, and it takes its movement from the main spindle. Automatic key: It is used to turn on the main spindle and change the direction of rotation of the main spindle.
To save milling cutter
Review Questions
Milling Processes
Or angle milling, where the flat grinding surfaces must be neither parallel nor perpendicular to the milling axis. The steps of the slotting process in the milling machine are similar to the surface preparation process, but the depth of cut is greater and the width of the cut is smaller. It is a type of angular milling, where the flat milling surfaces must be perpendicular to the milling axis.
It is a form of shoulder milling in which the flat milling surfaces must be parallel to the milling axis. Hold the workpiece, as shown in Figure Mill-16, with the vise (the workpiece surface must be parallel to the milling axis). It is a form of shoulder milling in which the flat milling surfaces must be perpendicular to the milling axis.
The steps of the miter sawing process on a milling machine are similar to the sawing process on a milling machine. The steps of the common process on a milling machine are similar to the sawing process on a milling machine.
Turning Workshop
- Objectives
- Introduction
- Workshop prerequisites
- Main parts of lathe
Gearbox: It takes its motion from the motor and gives these speeds to the power screw shaft to get various speeds for the carriage. Tail stock: As in figure Lathe-2, it is located on the lathes in the opposite direction from head stock, and it can be adjusted to any position on the lathe bed with a screw. The carriage: It holds the cutting tool, and it slides on the bed in a longitudinal direction.
Drive Screw Shaft: It is a cylindrical column that extends down the bed and rotates from the gearbox. Splined Shaft: It is a threaded cylindrical shaft that rotates from the gearbox and is used to move the carriage automatically. Main Spindle: As shown in Turn-3, it supports the chuck and provides a rotating main cutting motion for the workpiece at different speeds.
Turret: As in Figure Turn-4, it holds at the top of the composite rest, and is used in the cutting tool holder. Cross slide: It is located at the top of the bed and carries the composite rest.
Turning Processes
As in Figure Turn-14, feed the raw material and adjust an appropriate machining length to prevent a collision between the cutter and the drill chuck. As in Figure Turn-15, adjust the height of the cutter so that it is in the middle of the raw material surface to get a fairly turning process. Feed the raw material and adjust a suitable machining length to prevent collision between cutter and drill chuck.
As in Figure Turn-20, the tail stock is moved to close the gap between the cutter and the raw material surface. As in Figure Turn-23, drill a suitable hole in the required surface to allow easy access to the internal turning tool (this can be done on a drill or lathe). Feed the raw material and adjust a suitable machining length to prevent a collision between the cutter and the chuck.
As in figure Draai-25, a grinding device -with a special electric motor- must be fixed on the carriage instead of the turret as shown in the following figure. Feed the raw material and adjust an appropriate length to prevent a collision between the grinding wheel and drill hole. As in figure Turn-26, hold the raw material with chuck jaws in a suitable and secure manner.
Move the carriage by hand to make the grinding wheel close to the raw material level. As in figure Turn-29, adjust the height of the cutter precisely to avoid curved edges of tapered surfaces. Adjust an appropriate depth of cut (workpiece is machined to the larger diameter. See figure Turn-30).
As in Figure Turn-31, parting is the process of cutting a piece from stock while it is in the lathe. As in Figure Turn-32, this process uses a sharpened tool with a 5° side bevel and no back bevel. As in Figure Turn-34, the steps of the lathe shoulder process are similar to the longitudinal turning process.
As in Figure Turn-35, the steps of the shoulder process on a lathe are the same as with square shoulders, using a side turning tool set at the desired angle of the shoulder. The most commonly used types of grooves are square, round, and V-shaped, as shown in Figure Turn-36.
Shaping Workshop
Objectives
Classification of shaping machine: As in figure Shaper-2
Cutting tools of shaping machine
Review questions
Shaping Processes
Manually push the workpiece up towards the cutting tool - until a proper and tight position is achieved between the cutting tool and the workpiece - with the appropriate handle of the machine table. At the beginning of the operation, there should be a slow manual contact between the surface of the workpiece and the teeth of the cutting tool. The steps of this procedure are similar to the previous steps of the procedure, but the width of the incision is smaller than in facial contouring.
Grinding Workshop
- Grinding machine components: See figure Grind-1
- Purpose of the grinding processes
- Grinding wheel
- Final product of grinding process
A grinder, often shortened to grinding machine, is any of several power tools or machine tools used for grinding, which is a type of operation using an abrasive wheel as a cutting tool as in figure Grind-2. As in figure Grind-3, grinding is used to finish the workpieces with a high surface quality (low surface roughness) and high accuracy of shape and dimensions.
Grinding Processes
Drilling Workshop
Geometry of drilling cutting tool: As in figure Drill-2
Drilling operations
Types of drilling machines
The components of a radial boring machine are similar to conventional boring machines, but with more heads and tools.
Drilling Processes
In this case, the steps of opening the large hole in a drilling machine are the same steps of the previous process, but the cutting procedures must be repeated several times. Each time, a larger drill bit must be used to get a larger hole than a previous hole, and this must be done until the required hole diameter is reached.
Sawing Workshop
Types of sawing machine
Sawing Process
In this case, the miter saw steps are the same as the previous cutting process, but the vise must be tilted at the proper angle to set the workpiece at the desired angle.
Sheet Metal working and forming Workshop
Sheet Metal Process
As in figure Sheet-6, the hydraulic shearing process depends on the shearing rules between the two blades.
Welding Workshop
Types of connector
Types of welding methods
Gas welding is one of the most common welding methods, where the edges of the base materials, but also the filler material, melt due to the generation of heat generated by the combustion of a gas mixture (suitable gas fuel) with air or pure oxygen. The welding process is completed after the molten metal has frozen in the weld zone. One or more types are used to isolate the welding area from the air.
The welding process is completed at the point or place where the heat is increased by pressure through polarity. This method of welding is easy to complete with high productivity, so it is considered an economical method compared to other welding methods.
Welding Processes
As in Figure Weld-12, holding the electrode too close to the joint lowers the welding voltage, increasing the likelihood of the electrode sticking to the base material. As in Figure Weld-14, adjust the driving angle: the driving direction about 0 to 15 degrees. As shown in Figure Weld-15, adjust the advance speed: Your advance speed should allow you to keep the arc in the first third of the weld pool.
As in Figure Weld-16, too high travel speeds also reduce penetration and will create a thinner/undersized bead. Resistance spot welding (RSW) is a process in which contacting metal surface points are joined by the heat obtained from resistance to electric current. The attractive thing about spot welding is that a lot of energy can be delivered to the site in a very short time (approx. 10-100 milliseconds).
Spot welding is generally used in sheet metal working or, for example, when joining steel plates in bodywork and vehicle production. As in Figure Weld-17, when joining the workpieces by spot welding, the workpieces must be accurately aligned with each other, since correction after welding is not easy. As in Figure Weld-19, when the electrodes are placed correctly, the current flows, the current turns on and flows from one electrode to the other at very high power.
The time during which the electric current must flow through the workpieces varies depending on the material and workpiece thickness. As in figure Weld-20, if the parts are tightly connected, the electrodes are removed to repeat the process at the next weld point.
