Burri BZ331 CNC Generative & Profile Gear Grinding Machine

Description

The Burri Model BZ 331 represents one of the original products in Burri's business portfolio from their first rebuilds starting in 2009. The foundation of the Burri BZ 331 / BZ 362 machines are built from Reishauer® machine types RZ 362, RZS, RZ 361 as well as RZ 301 and AZA models. Only the original machine bed, helix angle adjustment and grinding wheel housings are used - the remainder of the componentry are entirely developed by Burri.

After modernization, the machines are supplied as new machines with CE conformity and new technical documentation. The technical equipment is essentially at the level of a new machine with an unbeatable energy efficiency as well.

The machines are equipped with a completely new PC control unit with high performance Ethernet network, compact I/O system, modular drives with energy recovery system, digital absolute precise encoders, CNC control on all axes, high-dynamic synchronization module, dialogue-based user interface, remote diagnosis system (internet access on the machine to be provided by the customer), data management via Compact Flash, USB interface, etc. The electrical cabinet is fixed to the machine - also during transport of the machine.

Here are some features with these machines that highlight NEW v. OLD:
• Cutting speed 63 m/s (3.500 rpm – before: 1.900 rpm).
• Multi-start grinding (up to 5-starts depending on module - originally only 1- start was possible).
• Speed of work piece drive 750 rpm (before: max. 300 rpm) including oil centrifuge functions adjustable at the end of the cycle.
• Max. gear diameter 330 mm.
• Large data memory for several hundred gears.
• Min. wheel root diameter reduced from 280 to 250 mm. Thus you will have approx. 30 % additional grinding wheel material.
• Automatic adjustment of the centering sensor by the machine software (operator no longer needs to make adjustments).
• Automatic set up of profiling/grinding by acoustic touch control.
• With the new B & R control unit the machine has a very quick set-up time and is very flexible and thus it is suitable for small and large batch production.
• The ultra-modern B & R Acopos Multi driving concept and the compact hydraulic has reduced the power consumption of the machine to approx. 1/3.
• Profile Grinding Capability.

With all of the above-mentioned changes, all components of the machine that were liable to become maintenance problems are eliminated, such as electric clutches, indexing plungers, lead screw of the dressing slide with all the change gears, etc.

Work piece support with Z-axis: The new Z slide is modified from hydraulic to servo drive with linear guides, ball bearing spindle and linear measuring system. The new work piece spindle (machine table) is a direct drive with water-cooled Torque motor; thus, the machine can now handle multi-start processing of small, helical gears. The max. speed has almost doubled from 300 rpm to 750 rpm.

The machine can be operated with a collet system with 30/65 mm ball diameter and also with integrated clamping systems. With the above-mentioned changes all mechanically sensitive components such as crown gear, backlash compensation, oil ring, scraped guides etc. are dropped.

Rebuilding & improving existing generating grinding machines is in Burri's DNA since 2002. Along the way, NEW machines were developed along with rebuilds. Now there are more than 100 Burri machines sold and in operation throughout the world. Even mother machine builders use Burri for the more 'difficult' applications...