Planer (machining) (9:50 am 01.04.2011)
Planer and shaper are popular single point precision machining methods. A shaper operates by moving a cutting tool backwards and forwards across the workpiece. The workpiece mounts on a rigid square table that can traverse sideways underneath the reciprocating tool, which is mounted on a ram. The table motion is controlled by a precise feed mechanism. The ram slides back and forth about the workpiece and the tool can be positioned to cut the flat surface on the top of the workpiece. A Planer is a type of machining tool analogous to a shaper, but larger and with the entire workpiece moving beneath the cutter instead of the cutter moving above a stationary workpiece. Planers and shapers are generally used for two types of work: generating large accurate flat surfaces and cutting straight microgrooves. Modern planers are used for producing precision stamping dies and plastic injection molds for light-guiding plates of liquid crystal displays, large scale linear fresnel lenses.
( J. Paulo Davim, Mark J. Jackson, Nano and micromachining, page 178)
Carriage ( about lathe) ( 10:04 am 01.04.2011)
Carriageis mounted on the outer guideways of lathe bed and it can move in a direction parallel to the spindle axis. It comprises of important parts such as apron, cross slide, saddle, compound rest and tool post. The lower part of the carriage is termed the apron in which there are gears to constitute apron mechanism for adjusting the direction of the feed using clutch mechanisms and the split half of nut for automatic feed. The cross slide is basically mounted on the carriage, which generally travels at right angles to the spindle axis. on the cross slide , a saddle is mounted in which the compound rest is adjusted which can rotate and fix to any desired angle. The compund rest slide is actuated by s screw, which rotates in a nut fixed to the saddle.
(Rajender Singh, Introduction to basic manufacturing processes and workshop technology, page 410)
Planer and shaper are popular single point precision machining methods. A shaper operates by moving a cutting tool backwards and forwards across the workpiece. The workpiece mounts on a rigid square table that can traverse sideways underneath the reciprocating tool, which is mounted on a ram. The table motion is controlled by a precise feed mechanism. The ram slides back and forth about the workpiece and the tool can be positioned to cut the flat surface on the top of the workpiece. A Planer is a type of machining tool analogous to a shaper, but larger and with the entire workpiece moving beneath the cutter instead of the cutter moving above a stationary workpiece. Planers and shapers are generally used for two types of work: generating large accurate flat surfaces and cutting straight microgrooves. Modern planers are used for producing precision stamping dies and plastic injection molds for light-guiding plates of liquid crystal displays, large scale linear fresnel lenses.
( J. Paulo Davim, Mark J. Jackson, Nano and micromachining, page 178)
Carriage ( about lathe) ( 10:04 am 01.04.2011)
Carriageis mounted on the outer guideways of lathe bed and it can move in a direction parallel to the spindle axis. It comprises of important parts such as apron, cross slide, saddle, compound rest and tool post. The lower part of the carriage is termed the apron in which there are gears to constitute apron mechanism for adjusting the direction of the feed using clutch mechanisms and the split half of nut for automatic feed. The cross slide is basically mounted on the carriage, which generally travels at right angles to the spindle axis. on the cross slide , a saddle is mounted in which the compound rest is adjusted which can rotate and fix to any desired angle. The compund rest slide is actuated by s screw, which rotates in a nut fixed to the saddle.
(Rajender Singh, Introduction to basic manufacturing processes and workshop technology, page 410)
Abrasive Wear (16:04 03.04.2011)
Abrasive wear is defined as wear due to hard particles or hard protuberances forced against and moving along a solid surface. This form of wear in metals is most frequently caused by non-metallic materials but metallic particles can also cause abrasion. Generally a material is seriously abraded or scratched only by a particle harder than itself.
(Joseph R. Davis Surface Engineering for Corrosion and Wear Resistance, page 56)
Addition Polymerization (16:34 03.04.2011)
Addition polymerization is the polymerization of the monomers by a chain mechanism involving active sites on the growing chain. Addition polymerization is frequently accomplished with unsaturated monomers, it is also called vinl polymerization when the unsaturated monomer contains the group -CH2=CH2-
(Charles A. Harper, Edward M. Petrie, Plastics materials and processes: a concise encyclopedia page 13)
Addition Polymerization (16:34 03.04.2011)
Addition polymerization is the polymerization of the monomers by a chain mechanism involving active sites on the growing chain. Addition polymerization is frequently accomplished with unsaturated monomers, it is also called vinl polymerization when the unsaturated monomer contains the group -CH2=CH2-
(Charles A. Harper, Edward M. Petrie, Plastics materials and processes: a concise encyclopedia page 13)
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