5 x D drilling in filler necks for piston accumulators

 

 

 

The new KOMET KUB Pentron™ indexable insert drills with 5 x D design enable reliable production of filler necks for piston accumulators from one side. “And all at incredible cutting speeds,” according to Herr Klingelhöfer, the works manager responsible for machining at Bolenz & Schäfer.

 

 

The particularly thick-walled filler necks are testament to the robustness of the BSD piston accumulators, which are designed to store hydraulic energy in order to absorb pressure surges, suppress pulsation and/or even out flow rates by compressing nitrogen. They are placed in the pistons that are made of forged material and are manufactured in various versions, including customer-specific connection solutions. Until now, it was necessary to work from two sides to create these bores due to the length/diameter ratio and, because of the particularly tough material and awkwardly long chip formation, with comparably cautious feed rates but high cutting speeds. Furthermore, the wall thicknesses of the filler necks often meant that the maximum permissible drilling depths specified by the tool manufacturers had to be pushed to the limit or even exceeded. A situation that does not exactly contribute to process reliability and which causes tool breakage when there is chip accumulation, if not before. “With the 5 x D version of the KOMET KUB Pentron™ , there are practically no limits. We can machine all filler necks from one side, which makes machining considerably more economical and reduces our chip control problem,” reports Herr Klingelhöfer enthusiastically.

 

Successful trial in the lathe

 

At Bolenz & Schäfer, the KOMET KUB Pentron^™ was first used in a lathe for the series production of filler necks. Even though the fixed application for indexable insert tools with large length/diameter ratios presented a challenge in terms of chip removal, the trial was an immediate success under these difficult conditions. In the meantime, the KOMET KUB Pentron^™ was also used in a flexible machining centre for manufacturing smaller batches of filler necks. Herr Klingelhöfer gives the cutting speed that was reached here as a “moderate” 280 m/min, knowing full well that he has not reached the limits of a reliable manufacturing process with it.

 

 

 

 

With its brands KOMET^®, DIHART^® and JEL^®, the KOMET GROUP is a leading global manufacturer of precision tools for bore machining, threading and reaming. The group has been at the forefront of innovation in the sector for over 90 years - a tradition that began with the early insert drills and that continues today with their mechatronic tool systems. The company currently employs more than 1,600 staff in its 20 subsidiaries and is represented in around 50 countries.

 

 

Pictures:

Picture 1: The connection bores in the thick-walled filler necks for the piston accumulators require large drilling depths.

 

Picture 2: The filler necks are created in both sides of the pistons made from forged material.

 

Picture 3: Bolenz & Schäfer uses the KOMET KUB Pentron^™ in the machining centre, but also  statically in the lathe.

 

 

 

Komet-0907-Pentron Bolenz&Schäfer-short.doc