Coating

Future-oriented technologies for your products

Nano honing

THE FUTURE in engine design

Thermal spray coats in cylinder bores of internal combustion engines are high-performance materials of the future. Energy efficient engines with low friction, reduced length and lower weight as well as lower production costs can be achieved due to the new process chain for the manufacture of cylinder bores.

To this end, the process chain includes the following processes:

  • Laser Roughing
  • PTWA coating
  • Overspray jets
  • Honing

Principles of Nano honing

Laser roughening (pre-treatment) is required as a variatnt of precision boring in order to achieve a high degree of adhesion when coating. Laser roughening is realized through cutting processes and combined processes consisting of cutting and forming.

The following PTWA coating (Plasma Transferred Wire Arc) works with a plasma light arc in which the supply wire is melted and then sprayed onto the cylinder bore. This results in a hard, wear-resistant, ductile and easy to hone cylinder liner coating.

After the thermal coating follows the overspraying jets in which overspray particles are removed from the casting surfaces below the coated cylinder bore by means of water jets. Expensive masking is no longer required and the process chain is thereby ready for production.

The subsequent honing, a multiple-step precision machining process, creates the low-friction surface with a high degree of dimensional and form accuracy in the cylinder liner which is needed for the engine.

Components of Nano honing

The combination of the single processes roughening, coating and honing is necessary to implement manufacturing of nano honing.

The roughening with Gehring tools occurs with feeded processing spindles. During thermal coating the actual cylinder lining is sprayed-on with little iron particles. Thereby RSW, PTWA, LDS or APS processes are used.

The nano honing closes with a specific aligned honing process on Gehring honing machines. If required, one can integrate washing operations before coating as well as overspray cleaning after coating in the overall process.

During the coating pocess, possible occured particle disposals under the boring can be removed with overspray cleaning. For this cleaning, a water-soluble coolant under high pressure is brought in the appropriate range through a steel tool.

Thermal coating of aluminium

Laser roughened surface profile

The process chain of nanohoning

The Sturm Advanced Cylinder Coating System (ACCS) is the efficient and modular solution for producing coated cylinder surfaces in modern crankcases or liners. The thermal spraying process uses a single wire as starting material and allows for a variety of coating properties.

In order to be able to offer the entire process chain „roughening - coating - honing“ Gehring has integrated the ACCS-TWS (Thermal Wire Sprayer) into its technology center. The loading and unloading area of the ACCS-TWS is equipped with the Cylinder Inspector. This enables direct quality control before and after coating as well as an automatic thickness layer adjustment possibility.

Trust in the technology leader with many years’ experience and global presence! Innovative technology combined with an economical mindset sets us apart.

The objective of Nano honing

An overall result of this process chain is a marked reduction in friction, which considerably contributes to reducing fuel and oil consumption.

Therefore, we can additionally ensure a considerable contribution to modern internal combustion engines with a high degree of energy efficiency, low emission values and longevity.

Finished structure after honing

Your benefits

The nano honing process chain leads through a combination of roughening, coating and honing technologies to particularly friction reduced and tribological optimated cylinder lining.

Thus, a wear-resistant coating with system-immanent porosities as lubricate volume and at the same time very fine honed surface is realized.

Our Products:

powertrainhone

Our model series powertrainhone is especially optimized for the machining of engine blocks and cylinder liners. Whether machining of cylinder or crankshaft bore, whether modular variant or transfer line, we offer the right solution.

Our POWERTRAINHONE