Customer’s Initial Machining Process:

• Used a conventional lathe.
• Manual 3 jaw chuck.
• Feeding HSS pilot drill manually
• Feeding HSS finish drill manually. .
• Heat treating the material and then boring using a VMC
• Total machining time of 20-30 minutes.

Our machine concept & Implementation:

Features and Specs:

• Heavily ribbed, fabricated and stress relieved structure.
• Atop the base, a stationary fixture is provided. The fixture consists of V blocks and hydraulic clamps to clamp the component.
• On one side the fixture, drilling head is mounted on hydraulic cross slides. Sliding surfaces is made of LM guideways and blocks. The slide has a stroke of 300 mm.
• The drilling head is driven by a 20HP motor connected to the spindle through timer belt and pulley mechanism.
• The drilling head’s motor are routed through VFD for stepless speed variation from 300-1500 RPM.
• The slide is driven through a servo motor which is coupled to a ballscrew through a 1:4 ratio servo reducer to provide feed rates of 10mm/min to 7500mm/min.
• The machine is provided with spindle through coolant and chip flushing.
• The machine will be provided with complete machine enclosure.
• The machine will be provided with PLC programmed auto-cycle. A touch screen HMI will be provided for machine parameter setting and trouble shooting.

Sequence of Operation:

• Load the component on the fixture and press auto-cycle.
• The component gets clamped.
• Through coolant is switch on. The drilling head spindle starts, drills the component with 3 pecking cycles and retracts. Spindle stops
• The finish drilling head moves, drills the component to the finish bore and retracts. Spindle and coolant stops
• The component clamp disengages.

Cycle Time:

The cycle time of the machine from component clamp to unclamp condition consider the bore diameter Ø44x220mm is 180 seconds

Final Conclusion:

Lathe:

• Component setup time is high.
• Machining time is high
• Need of skilled operators.
• Due to manual feeding, operation is prone to operator’s fatigue, which may lead to loss in efficiency of production.
• Even though tooling cost is less, considering the machining time, operator’s salary, the overall cost is more.

U-Drilling and Boring SPM:

• No need of skilled operator. Cost of skilled operators is reduced.
• Uses U-drills with indexable inserts. Cost of tooling is reduced.
• The total drilling time is 3 minutes, instead of 15-20 minutes on a lathe. Efficiency is more than 6 times. Increases the productivity, increases profitability, increases the scrap generation rate.
• Machine provided with adjustable V blocks and clamps, which can accommodate a variety of components.

Video: