MAPAL – Machining of Unstable Structural Parts

 

Thin-walled parts are used in a wide variety of applications. These components are often manufactured close to the net shape, but nevertheless require a great many machining operations. The particular challenge for these machining processes is that due to their design, these parts are very unstable and susceptible to vibration. That creates special demands upon the design of the process and the tools.

These parts are preferably machined in a single clamping system. In order to meet this demand and to make as many of the surfaces to be machined as accessible to the tools as possible, certain allowances have to be made in the clamping system. As a consequence, the workpiece is not optimally supported and tends to vibrate. Thin webs, voids and interruptions to be machined and widely fluctuating stock removals from the cast blank also call for special tool solutions. For large parts with many machining steps, this would require a huge number of tools. The merging of these steps using combination tools in order to reduce the non-productive times and the number of tool slots is an ideal solution.

Thanks to its vast understanding of the processes for the machining of unstable structural parts, MAPAL is able to offer cost-effective and reliable processes. Three aspects are of particular importance here. Firstly the adjustment of the cutting rate is a factor for reducing or avoiding rising vibration. Both vibration of the tool – which would result in short tool lives and poor machining results – and vibration of the workpiece have to be prevented. The latter would result in a recoiling of the part against the cutting edge and could cause damage to the tool. The second important adjustment in the tool design is the evaluation of the tool body. Vibrations can be reduced here by an appropriate design and choice of material. Furthermore, an intelligent arrangement of the cutting edges in form and position helps to keep the cutting forces low. And finally the machining process itself offers possibilities for reliable machining of parts susceptible to vibration. Reorganization and the choice of alternative sub-processes create a change in the distribution of forces that can increase the process reliability. For example, the use of a circular milling operation instead of a solid drilling operation can help to stabilize the process.

Please contact us for more information on machining of Structural Components.

– This article is an excerpt from Mapal Innovations – Process Solutions 

The Flex-Hone® Tool

 

 

 

 

 

 

 

The Flex-Hone® Process (Super finishing) produces a controlled surface condition unobtainable by any other method. It involves finish, geometry and metallurgical structure. A high percentage plateau free of cut, torn and folded metal (with radiused ports).

A resilient, flexible, cylinder honing tool with a soft cutting action. The abrasive (points) globules each have independent suspension that assures the Flex-Hone® to be self-centering, self aligning to the bore, and self-compensating for wear.

 

 

 

 

 

 

Specifically, it is a low-temperature abrading process that exposes the undisturbed base metal structure to produce a long wearing surface. It is a method of developing a surface on a metal part which is optically smooth and metallurgically free of any fragmented, amorphous or smeared metal from previous operations. It is accomplished at a low pressure where the “stones” float.

The particular type of Flex-Hone® crosshatch is extremely efficient in providing a multiplicity of oil grooves or valleys for oil retention as opposed to the often undirectional or uneven valleys common to the conventional type rigid hone. A crosshatch that usually remains as the cylinder wall has been wear-reduced by the FlexHone®.

Flex-Hone Applications

SURFACE FINISHING
The Flex-Hone® Tool is available in a variety of abrasive types and grit selections to provide the optimum surface finish on any base material. The Flex-Hone®, also known as the cylinder ball hone, is commonly used to reduce Ra, Rk and Rpk values while maintaining Rvk and Vo volume for oil retention. Using the Flex- Hone® Tool for surface finishing allows the sizing tools to do their jobs quickly and accurately without fighting surface finish. The Flex-Hone® is also used in adhesive bonding applications where a rougher surface is desired for bonding integrity.

DEBURRING
The deburring of cross drilled holes is an expensive, time consuming operation. The Flex-Hone® Tool can be used to remove burrs from cross drilled holes leaving a clean, radiused intersection. Because of its unique construction, the Flex-Hone® can be used online in machine tool applications or offline as a secondary operation.

 

 

 

The cylinder honing tool is self-centering and self-aligning to the bore so elaborate, rigid set-ups are not required. It is advisable to use the tool in the main bore into which the cross holes break. Best results are obtained by rotating and stroking the flex hone a few strokes in a clockwise direction, removing the tool from the part, reversing the spindle and then rotating and stroking the tool in a counter clockwise direction for a few more strokes. This forward and reverse rotation creates a more symmetrical deburring pattern.

 

 

 

 

 

 

PLATEAU FINISHING
Brush Research pioneered the concept of a plateau finish and is a strong proponent of the benefits of a cross hatch, plateaued finish. The concept involves using flex hones to remove the peaks produced by prior machining operations to create a substantially flat or plateau finish. A plateau finish created by the elimination of peaks allows rings and seals to seat without damaging their edges. The cross hatch pattern will aid in lubrication control and retention, reduce seepage in hydraulic and pneumatic applications and promote longer seal life.

 

Related Information:

Flex-Hone® Charts & Sizes

Flex-Hone® for Rotors

Flex-Hone® for Firearms

 

Horn + W&F Solutions

Horn and W&F Werkzeugtechnik have come together to offer customers a complete solution covering everything from the spindle to the tool cutting edge. The focus is on equipping Swiss-type lathes with a quick-change system. “By entering into this cooperation, we are filling the gap that exists in our offering between the cutting edge and the machine. It will allow us to respond rapidly to customer enquiries and optimise their machining processes”, says Managing Director Lothar Horn, Paul Horn GmbH. Under the deal, HORN will be responsible for selling W&F tool solutions from Großbettlingen all across the world via its subsidiaries and sales partners in more than 70 countries.

The cooperation also brings many advantages in the OEM area by making it possible to offer customers “everything from a single source”. Thanks to the experience of both partners, new solutions and optimisation approaches can be developed in next to no time. To begin with, the cooperation will focus on quick tool change systems for Swiss-type lathes and internally cooled whirling units. A special Horn catalogue for Swiss-type turning is due to be launched in the autumn of 2018.

The first jointly developed technology to have come out of the cooperation is JET-Whirling. The internally cooled whirling tool is a real USP of the whirling method. Having the coolant supplied directly to the cutting edge during whirling results in higher surface quality, improves the flushing action for removing chips and extends the life of the tool inserts. The tool system – comprising the W&F whirling unit and Horn whirling head – was officially unveiled at AMB 2018 in Stuttgart.

Please contact us for more information on solutions from Horn + W&F!

 

 

KNOLL: Central Systems

A completely automatic “System Solution” for the transport or treatment of chips or coolant. These are individual systems and components that are linked to form one complete system – a Central System.

A suitable system depends on the project requirements. This may be, for example, classical, rigid chip conveying systems (belt conveyors) or modern, flexible, cross-linked bulk goods transportation systems (pumping or suction technology). halls and machine layout, machining processes, materials, chip volume and length of conveying path, but also the degree of automation, flexibility, environmental stipulations, disposal costs and budgets are a selection of criteria which our planning experts take into consideration in the design of a suitable system.

KNOLL can offer you all required services, from planning to production to start-up, all from a single source. KNOLL customer service ensures safe and economical operation. Additionally if the system is to be expanded or reconfigured, KNOLL is the right partner for you.

Systems with Pump Technology
A conveyor and filter system with pump technology is suitable for fully-automatic chip transport from several processing machines to a central filter system. Cooling lubricant serves as the carrier medium.

Systems with Extraction Technology
A conveyor system with extraction technology is suitable for fully-automatic chip transport from several processing machines to a central collection point. Room air serves as the carrier medium.

Systems with Collecting Conveyors
Collecting conveyor systems are required to bring metal chips and small parts from production to a central collection point.

Systems for Chip Processing
The treatment of chips has many advantages: they are dry and separated by type, so disposal costs are low. Depending on the material, it may even be possible to sell the chips.

Accessories
As a supplier of complete solutions KNOLL offers customers all accessories for KNOLL Central Systems:

  • Pumps – For the mechanical-engineering and automotive industries
  • Swarf Trolleys – For stable emptying
  • Coolant + Lubricant Tempering equipment – For preheating and heating or cooling of cooling lubricants and other media
  • Foreign Oil Separators – For maintaining cooling lubricants
  • Coolant + Lubricant metering and mixing devices – For metering and mixing stable and homogeneous cooling lubricants or solutions
  • Magnetic Separators – For cleaning cooling lubricants to remove ferromagnetic contaminants
  • Chip Centrifuges – For automatically de-oiling short metal chips
  • Chip Compactors – For briquetting (compacting) metal chips as an economical and ecological alternative to chip processing
  • Lifting + Tipping Devices – Equipment for emptying the contents of chip trolleys or material hoppers into containers, chip mills or centrifuges

 

Please contact us for more information on Central Systems from KNOLL.

 

 

HORN High Speed Whirling

 

 

HIGH-SPEED-WHIRLING
New technology for shorter machining times. Whirling and turning performed simultaneously saves time and reduces the material volume which has to be removed by whirling inserts. High feed rates shorten process time and increase productivity.

• Long tool life and excellent surface quality as a result of pre-turning the thread diameter
• Machine and Process Technology partners Index / Traub

Please contact us for more information on this new product.