Machine Tools and Metalworking Processes: A Comprehensive Look
Filer (Roughing and Finishing of Parts)
A machine tool is characterized by the cutting motion it has. The tool has the advance and penetration of making the piece. The machine consists of a base casting that houses the drive system coupled to an oscillating crank mechanism with a fixed and a hinged fulcrum. This provides reciprocating linear motion to a sliding carriage, called a ram, in which the tool is fixed. The length of the advance stroke of the ram can be adjusted by varying the length of the crank. The piece is secured to the table by means of some clamps. The movements can be performed manually by acting on cranks paths coupled to screw drives, or can be automatic.
Planer
Variation of the shaper, for larger pieces. It carries a table where the pieces make a reciprocating linear motion, so that it is cut when the tool strikes the workpiece, which is slower than the kick. The tool is mounted on a swivel attached on a vertically moving beam that regulates the penetration and the forward movement does the tool moving horizontally on the beam by means of a screw nut.
Drill
The exercise machine tool movements and cutting penetration.
Lathe
It is a machine tool in which the motion is rotary cut and piece while it has the forward movement and penetration of the tool.
- Bed: Is the support of the rest of the machine and is usually constructed of cast iron molded in one piece.
- Fixed head: It is a box located on the side of the bed where the main axis normally adjusts the hole. The part is fixed by a plate and in the internal or are mounted the gears and pulleys that regulate speed.
- Mobile head: It is situated on the bed, the other end of the fixed head and slides down the droughts of the bed, possibly anchored to the bench by screws. It supports in turning very long items, when not enough restraint to the plate.
- Home Shopping: Slides on the guide rails of the bed by a rack and pinion system with a manually operated steering wheel and that is the tool provides the forward movement and penetration. In it are mounted on cross slide, that provides insight to the movement of the tool, and the saddle, that is used to approximate it to the workpiece.
- Safety of progress: The head is positioned below a fixed speed gearbox, that regulates the rotation of the screw thread.
- Tray: Located below the machining area and its mission is to collect the detached chip during machining.
- Capacity: Is the production of straight cylindrical surfaces of revolution.
- Facing: It consists in obtaining a flat surface perpendicular to the axis of rotation of the piece.
Sawing
- Characteristics of a saw:
- The disposal of the tooth (that prevents the piece brush with heated wavy toothed, jagged frolicking)
- Degree of cut (number of teeth per cm leaf length)
- Step (distance between two consecutive teeth)
- Thread per inch (number of teeth per inch, step 6-7 coarse teeth per cm, step through 8-9 teeth per cm and fine pitch of 12 to 13 teeth per cm)
- Material (carbon tool steel and the tungsten alloy or chrome)
- Size (measured in mm)
- Angle of Ataka is 20 to 30 º.
Blade
- Characteristics of material: That has to be machinable, because that influences the hardness of the tool, the temperature.
- Tools used: Special steel Carbon tool, vidi wolfragmio carbide and diamond.
- Movements of work: Cutting motion tangent to the surface of the material, forward movement parallel to the surface of the material and penetration movement perpendicular to the material.
- Cutting speed: Relative speed of the workpiece and the tool. The softer the material, the faster.
- Cutting force: Force required to perform the operation (Fc, F, Tp).
- Cutting angles: Alpha, angle of incidence, tool surface, beta, edge angle, face to face of the blade, range, angle of Ataka, the tool perpendicular to the surface; alpha + beta, cutting angle.
- Lubrication in the cut: Always be lubricated and that is done is drilling in the ratio 1 to 100 of water coolant.
Drawing
Is hammering on the side of a bar to give the required form, reducing and increasing section length.
Upsetting
Is the process contrary to the drawing. Is to hit the ends of the billet to reduce its length and increase its section.
Degüello
Sudden loss of section by first cutting the starting point and then make a stretch and finished with a flat.
Bending
Performed on guides prepared for this purpose. If the radius is small is called bent.
Punching and Drilling
Separates from a thin piece a portion of the material by a blow to press a certain way.
Pattern
Block out objects based on the shape of a mold. This piece is placed between two molds and put through a press or hammer blow.
Extrusion
Involves heating a metal billet to a second temperature near the melting point and pass through pressure through a hole shape.
Trokel
Drilling into sheet metal with holes sized quickly and without deformation of the sheet.
Stamping
Is a process that is to deform a metal plate so that it acquires a certain way. The thickness of the sheet will remain constant.
Drawing
A method for obtaining wire. Consists of passing a wire through a hole whose diameter gradually diminishes, reducing its section and its length increased.