Advantages of lapping

Advantages of Lapping

•  Improves surface finish by eliminating the peaks and valleys. 
• Create maximum bearing area between the mating surfaces. 
•  Improves service life of the moving parts which are subject to wear. 
• Improves geometrical and dimensional accuracies. 
•  There is absolutely no distortion in the component after lapping since no clamping devices are used. 
• Minimizes the necessity of re hardening hardened parts because of less heat generation. 
• Accessible flat surfaces of parts of any shape and size and any type of material can be lapped.        
• Simple carrier plate design is enough to accommodate the component for lapping (i.e.) complicated fixture is not required. 
• Any unskilled operator can work on the machine.

Accuracy, applications and features of GMT Planetary Lapping Machines

Accuracy:		Planetary Lapping Machine Lap plate with work carriers Optical flat
	One light band to two light band over 75Ø component. (i.e. 0.3µ to 0.6µ over 75mmØ).
	Surface finish : 0.2µ Ra.
	Parallelism : 0.002mm over 75mmØ.
Applications :
These machines can be very sucessfully used in:
	Electronic industries for lapping silicon wafers, germanium wafers, ferrite and piezo electric ceramics.
	Pump industries for lapping mechanical seals made of tungsten carbide and ceramics.
	Air compressor industries for lapping compressor valve plates.
	Automotive industries for lapping thrust washers and distance pieces used in power steering.
Features :
	The machine is constructed on a rigid welded hollow section steel frame, which houses a AC motor offered with variable frequency drive and a worm and worm wheel reduction gear unit.
	The central gear, internal ring gear and work carriers are driven a AC motor.
	The drive from the AC motor is taken through a worm and worm wheel reduction unit and then goes centrally through the main spindle to the central gear to the internal ring gear, through the work carriers.
	The drive from reduction gear unit is through a unidirectional clutch arrangement. This arrangement ensures a smooth motion when the machine is started. This feature also eliminates breakage of fragile components like silicon and germanium wafers while starting and stopping the machine.
	Both the lap plates are stationary. The differential motion given to the work carrier results in a random figure of '8' motion. This ensures that the component comes in contact over the entire area of the lap plate in so far as is feasible in line with the geometry of the component.
	A special camel back straight edge permits rapid and accurate assessment of the flatness of the lap plates.
	A set of special cast iron lapping gears are supplied with the machine for relapping the top and bottom lap plates.
	An independent slurry pump feeds the mixture of abrasive and oil to an abrasive feed assembly.It is then distributed through a spider to the working face by means of strategically located holes. A separate stirrer motor is attached with the pump to continuously stir the abrasive with oil.
	The main spindle bearings are sealed against ingress of the abrasive slurry. The used slurry is carried away by a suitable arrangement and is collected in a removable tank.

Advantages of lapping

What is lapping? Lapping is the first mechanical precision finishing  operation in done to achieve high dimensional accuracy. It helps you achieve positive sealing by obtaining high degree of flatness and surface finish. The advantages of lapping for obtaining fine flatness and surface finish have long been recognised by production and design engineers. Advantages: A wide variety of materials can be lapped. Flatness to one light band (0.0003 mm) on 100 dia. Surface finish to less than 0.2 µRA.
	Some reasons why lapping machines help to transform a costly, rarely used, hand operation to a fine accuracy, economical process:-
Parts of different shapes, thickness and material can be lapped.GMT has supplied lapping machines to lap various metals, plastics, glass, ceramic and granite. Because the lap plate continuously maintains its flatness, production is not interrupted. Appropriately selected diameters of the conditioning rings result in optimum lapping area. Lapping cycles are controlled by an automatic and adjustable digital display times.