In this scenario, the springs have reached the end of the design life cycle and should be replaced after two years. An example: a process with 3 to 4 tool changes per minute (many do much more), with 2,000 operating hours per year (one shift), means between 360,000 and 480,000 cycles are made per year. This may sound like a big number, but tool changes add up quickly. Small-diameter springs lead to highly stressed springs for tool clamping, and even more so during tool unclamp.Ī typical drawbar spring stack is designed to last approximately 1 million cycles. Small bearings necessitate the use of small diameter springs to fit into the spindle arbor. High RPM is often an important design criterion for a spindle, meaning the use of small diameter bearings makes sense from an engineering standpoint. Machining centers with automatic tool clamping systems typically use Belleville/disk spring stack to hold a tool in the spindle, with a hydraulic cylinder used to overcome the spring force to unclamp the tool. Predict problems with the spindle's Belleville / disk spring stack For HSK forms E and F, correct clamping force is crucial because there are not drive keys or dogs to transmit torque–the system relies entirely on the power drawbar's holding force. Because the HSK interface seats both on the tool holder taper and flange, dimensional tolerances are extremely tight. The HSK taper relies on an interference fit between the spindle and tool holder tapers, meaning drawbar force must be sufficient for the tool holder to properly seat. Insufficient tool holding force can quickly wear or damage the critical spindle taper resulting in loss of machine accuracy and an expensive repair bill.įor the HSK taper, wear and damage on the spindle taper are even more detrimental.

Protect your spindles and ensure machining accuracy A rigid interface will improve tool life by reducing chatter and excess wear, and in turn improve workpiece finish. Walter’s other existing A3000 anti-vibration boring bar product line offerings do not require the A2201 intermediate adaptors, and cover a diameter range of 1-2' and 25-50mm they are also offered with Capto C4, C8 and HSK-T 63-100 connections.Correct tool holding force ensures that the spindle-tool holder interface is as rigid as possible. Read: Metalworking Technologies Targeting Mold BuildersĬomplementing the A3001, Walter offers Capto C6, C8 and HSK-T 100 connections, and QuadFit precision (± 0.002 mm) quick-change exchangeable heads for decreased downtime and boosted versatility. The new tool is available with both negative and positive inserts. The vibration dampening system is preset at the factory, eliminating the need for fine-tuning of the dampening function prior to use, the company says. Unlike conventional steel or solid carbide boring bars that are often ineffective at length/diameter ratios beyond 6xDc, Walter’s Accure∙tec A3001, with its patented vibration dampening system, is said to excel at length/diameter ratios beyond 6xD up to 10xD. With the A3001 and the A2201, Walter has increased boring bar diameters to 2.5-4' and 60-100 mm.

The standard A2201 is an offset adaptor for reduced radial forces, greater stability and provides more space between the boring bar and the bore wall for improved chip removal with very deep bores. Walter USA has expanded its Accure∙tec anti-vibration boring bar line with the addition of the A3001 boring bar in combination with A2201 intermediate offset adaptor for larger diameter bores. It provides for fast, productive counterboring and internal profiling of parts in industries such as aerospace, oil and gas and general metalworking.

Capto c6 test bar