The Winning Choice

ADO-TRS 3-flute coolant-through carbide drill and VPO-DC-MT synchro tap enable stable drilling and tapping in the production of planetary bearing hubs for gearmotors in spheroidal cast iron

Andrea Severi | OSG Italia

Time savings in the production of large-size components can often make a significant difference to a manufacturer’s bottom line. Achieving a 50 percent reduction in tapping time was one of the recent key objectives of MPC Srl of Cesena (FC), Italy, a precision machining company that is always attentive to new technologies and process optimizations.

Founded in 1973, MPC is a leading solution provider of precision mechanical machining. MPC’s core business focuses on the production of gearbox components and corresponding parts. With over 40 years of experience, MPC has established a name for itself within the earthmoving and wind energy sectors. In addition to precision machining, the company is also versed in processes such as milling, turning, drilling and assembly, as well as custom manufacturing requests that fall within the metalworking and precision engineering sectors.

Founded in 1973, MPC is a leading solution provider of precision mechanical machining. MPC’s core business focuses on the production of gearbox components and corresponding parts. With over 40 years of experience, MPC has established a name for itself within the earthmoving and wind energy sectors.

Today with 36 full-time employees, MPC’s manufacturing facility is located in San Giorgio di Cesena, Emilia- Romagna, (FC), Italy, with an estimate 3,000-square-meter production space. MPC is a specialist in large-scale machining and has a production facility that is capable of turning parts up to 1,300 mm in diameter. Its factory is equipped with 23 numerical control machines including lathes and machining centers, with capabilities to optimize work cycles of large components in small to medium size batches.

MPC’s MCM Tank horizontal machining center with ASK-100 holder that is used for processing planetary bearing hubs for gearmotors.

Recently, MPC was looking to improve tool performance on a component made of GS-600 cast iron for a world-renowned client of gearmotors, drive systems and planetary gearboxes. Each part requires the threading of 30 holes in the size of M24, tolerance 6HX and at an axial depth of cut of 40 mm (through hole). The production is a 4-year contract with an estimated annual volume of 2,000 pieces.

MPC was originally using a competitor tap for the part, but encountered problems of sticking, bad surface finish and poor tool life. After consulting with its local tooling distributor Utensilmec, MPC invited OSG Italia’s technician to optimize the application with an aim to improve cycle time, tool life and the quality of threads.

Components for gearboxes made of GS-600 cast iron. Each part requires the threading of 30 holes in the size of M24, tolerance 6HX and at an axial depth of cut of 40 mm (through hole).

Upon a detail evaluation of the application, OSG recommended the VPO-DC-MT (EDP#: T0809234) M24 synchro tap with radial lubrication. The VPO-DC-MT is a powder metal straight fluted tap engineered to excel in cast iron and aluminum die cast applications. The high rigidity geometry of this tool combined with OSG’s V coating and the highly wear resistant powder metal substrate guarantee high-performance process stability.

The VPO-DC-MT is mounted on a Big Kaiser micro-compensated tap holder with a total presetting of 415 mm. The tool is programmed in an MCM Tank horizontal machining center and an ESSEX AR35 coolant is used. By switching to the VPO-DC-MT, the processing efficiency in cutting speed has doubled from the competitor’s 15 m/min to 30 m/min. The VPO-DC-MT is able to complete 5,000 threads for a total of 200 linear meters versus the original tool’s 1,660 threads for a total 67 linear meters. Comparing the cutting parameters of the previous tap, three minutes of cycle time can be saved per piece by simply switching to the VPO-DC-MT, which is equivalent to an annual cost savings of approximately 9,000 euros. Moreover, the VPO-DC-MT is able to triple tool life, which is an additional reduction in tooling cost. Last but not least, the surface quality of the thread crests has significantly improved, and chip sticking has been completed eliminated.

OSG’s M24 VPO-DC-MT synchro tap is mounted in the spindle for the production of a GS-600 cast iron component.

MPC couldn’t be more satisfied with the result, and OSG was given with another opportunity to analyze tooling performance of an eccentric hub. The second component is made of GS-500-7 cast iron. Each part requires the threading of 24 holes in the size of M20, tolerance 6HX and at an axial depth of cut of 40 mm (through hole). The production is a 5-year contract with an estimated annual volume of 1,000 pieces. Similar to the first GS-600 cast iron component, MPC was originally using a competitor tap for the production, and encountered problems such as chip sticking, bad surface finish and poor tool life. To further improve cycle time, OSG recommended the 17.5 mm diameter ADO-TRS-3D 3-flute carbide drill (EDP#: 8721750) and the VPO-DC-MT M20 tap with central lubrication (EDP#: 48300228).

An eccentric hub component made of GS-500-7 cast iron. Each part requires the threading of 24 holes in the size of M20, tolerance 6HX and at an axial depth of cut of 40 mm (through hole).

The ADO-TRS is one of OSG’s latest drilling innovations for ultra-machining efficiency in a wide range of materials. The ADO-TRS’ 3-flute specification offers greater balance than 2-flute drills, which are more prone to chattering. Moreover, the ADO-TRS enables superior roundness and improved positioning in terms of hole precision. With capability to excel under high-feed condition, the ADO-TRS is able to minimize contact time with the workpiece material, which reduces the probability of work hardening.

The ADO-TRS is highly recommended to be used in combination with the VPO-DC-MT synchro tap to achieve flawless holes for perfect threading. This combination of tools makes it possible to significantly reduce cycle time while maintaining superior quality.

OSG’s 17.5 mm diameter ADO-TRS-3D 3-flute carbide drill is mounted in the spindle for the production of the eccentric hub component made of GS-500-7 cast iron.

The ADO-TRS 3-flute carbide drill is mounted on a shrink-fit chuck from Big Kaiser with a total presetting of 305 mm. The VPO-DC-MT M20 synchro tap is mounted on a Big Kaiser micro-compensated tap holder with a total presetting of 370 mm. The tools are programmed in MPC’s MCM Tank horizontal machining center and an ESSEX AR35 coolant is used.

MPC was originally using a competitor 2-flute drill for the drilling process. The parameters of the competitor drill are 70 m/min in cutting speed, 0.3 mm/rev in feed per revolution, 1,274 rpm in spindle speed and 382 mm/min in table feed. By switching to the ADO-TRS, the cutting parameters are boosted to 90 m/min in cutting speed, 0.65 mm/rev in feed per revolution, 1,637 rpm in spindle speed and 1,074 mm/min in table feed, which is equivalent to a 181.2 percent increase in feed. The overall cycle time is reduced by 65 percent.

The VPO-DC-MT also exhibits similar increases in performance, where processing efficiency has doubled from the competitor tap’s 15 m/min to 30 m/min in cutting speed. The VPO-DC-MT is able to complete 5,300 threads for a total of 212 linear meters versus the original tool’s 1,700 threads for a total 68 linear meters. Two minutes of cycle time can be saved per piece by switching to the VPO-DC-MT, which is equivalent to an annual savings of approximately 3,000 euros. Similar to the first component, the VPO-DC-MT is able to triple tool life in the processing of the cast iron eccentric hub, which enables additional reduction in tooling cost.

From left, OSG Italia Sales Engineering and Marketing Manager Andrea Severi, MPC owner Stefano Soldati and MPC machine operator Luca pose for a photograph at the MPC facility in San Giorgio di Cesena, Emilia- Romagna, (FC), Italy.

MPC is always ready to satisfy the requests of its present and future clients by keeping up to date with the very best technologies available on the market. With significant cycle time reduction and quality improvement, OSG’s ADO-TRS 3-flute carbide drill and VPO-DC-MT synchro tap have demonstrated to be the winning choices for MPC.

For more information on OSG’s ADO-TRS, VPO-DC-MT, OSG Italia , MPC Srl and Utensilmec