Informations techniques rodage

Avec ses 100 ans ou presque d'activité dans le secteur du rodage, Sunnen dispose d'une mine d'informations techniques utiles qu'elle partage avec plaisir avec ses clients et le secteur en général. Les experts de nos services techniques ont recueilli les conseils, les conditions et les guides de rodage ci-dessous dans le but de vous assister dans l'optimisation de vos opérations de rodage.

Si vous avez toujours des questions après la lecture des documents correspondant à votre application de rodage spécifique, n'hésitez pas à contacter Sunnen pour obtenir une assistance technique supplémentaire.

Qu'est-ce que le rodage ?

Le rodage est une opération de finition finale effectuée sur une surface, généralement celle d'un cylindre intérieur, comme un bloc moteur automobile par exemple. Ce procédé d'enlèvement de métal est utilisé après le moulage, le frittage, le perçage, le forage afin d'obtenir une bonne géométrie de l'alésage et un état de surface précis. Abrasive stones are used to remove minute amounts of material in order to tighten the tolerance on cylindricity.

Ces dix dernières années, le rodage est devenu un processus correspondant en fait à une  finition d'alésage, car les valeurs de surmatière et de vitesse d'enlèvement de copeaux ont considérablement augmenté.

To learn more about honing, download our booklet Honing Technology, Tools and Machines.

Une brève histoire du rodage

L'idée du principe du rodage, c'est-à-dire le mouvement prédéterminé d'abrasion et d'enlèvement de matière régulier, est née il y a plusieurs siècles. Dans les années 1500, Leonard de Vinci a développé un outil pour l'usinage de tubes en bois. L'outil, composé d'abrasif, utilisait une combinaison de mouvement de rotation et de translation alternée.

Les outils de rodage tels que nous les connaissons aujourd'hui ont été développés au début du 20e siècle principalement dans le but d'améliorer les composants des moteurs à combustion interne. Les premiers outils de rodage étaient des bâtons de bois recouverts de papier abrasif. Des ressorts poussaient ces bâtons contre les parois du cylindre. Rapidement, des outils plus complexes ont été développés. En 1924, un outil de rodage avec cinq pierres abrasive doté d'un joint de cardan et d'une expansion par ressort fut breveté. Au début des 1930, le rodage a été utilisé pour la première fois dans une application de grande production : le rodage de bielles par empilage.

Glossary of Honing Terms

A part used with certain mandrels to adapt them to fit the spindle chuck on the honing machine.
Bague d'alignement
A concentric bushing used to minimize conical and parallel runout on machines with fully adjustable spindle noses.
Altered Stone
A standard honing stone, which has been shortened or otherwise changed for a specific application.
Oxyde d'aluminium
A man-made abrasive most often used in honing soft and medium hard steel. Designated by the letter "A" in the Sunnen stone code. Example: K12-A57.
Barrel Shape
A condition where the extreme ends of a bore are smaller in diameter than the middle.
Example of Barrel Shape
A condition where the extreme end or ends of a bore are larger in diameter than the middle.
Example of bellmouth
Blind Hole
A bore that is constricted or closed at one end.
Example of blind hole contrictedor Example of blind hole closed
The material that holds the abrasive grains together in a honing stone. Conventional Abrasives use fused clay or glass and are know as Vitrified bonded stones. Superabrasive stones use a metal bond, resinoid bond, or a vitrified bond.
A man-made abrasive (cubic boron nitride) especially useful for honing the tough alloy steels and other abrasive resistant materials. Designated by the letter "N" in the Sunnen stone code. Example: P28-NM55.
Liaison en liège
A bonding material composed of powdered cork and phenolic resin. Cork bonded honing stones are used where extremely fine surface finished is required. (Best results are achieved when used with bronze guide shoes.)
A honing process used to remove burrs, sharp edges or similar materials from rough bores.
A very hard abrasive grain, which is essential to the honing of carbide, glass and ceramic materials. Designated by the letter "D" in  the Sunnen stone code. Example: K8-DV57
Diamond Dresser
A diamond abrasive used to dress honing stones other than Borazon or diamond.
Des montages de prise de pièce
A method used to hold the workpiece while honing. Suggestions on different fixturing methods can be found in Data Files #107, 108, and 109.
Glazed Stone
A stone with cutting action impaired because the abrasive particles failed to break out of the bond when the cutting edges wore off. This condition shows up when the bond is too hard.
Patins de guidage
A part of the honing unit that stabilizes the bore being honed on the tool.
As applied to a honing stone, describes the strength of the bond that holds the abrasive grains longer; a soft bond will permit the stone to “break down” faster, exposing new sharp abrasive grains.
Hard-Tip Stone
A honing stone having a tip or end of harder abrasive than the body of the stone. Used for honing blind holes where relief cannot be provided.
Hard-Tip Stones
Used primarily for blind hole applications, the tip of the stone is engineered to be more wear-resistent than rest of the stone.
An abrasive machining process primarily used for stock removal, precision sizing, and surfaces. It is characterized by the use of a self-sharpening abrasive stone, a relatively large area of contact with the work, and relatively low cutting speeds.
Honing Length
The actual length of the surface being honed.
Pierre de rodage
An abrasive stick consisting of thousands of small abrasive grains bonded together.
Honing Unit
A complete honing tool consisting of an adapter (if required), a mandrel and wedge, stone(s), guide shoes, truing sleeve, and stone retainer or tension block.
Loaded Stone
A honing stone with cutting action impaired due to the cutting surface being partially covered with a foreign material, usually the material being honed. This condition is sometimes encountered when honing soft materials.
The part of a honing unit which holds and positions the honing stone and guide shoes in their correct relative positions.
Metal Bond
A powdered metal bond often used with diamond or Borazon abrasives. Designated by the letter "M" in the Sunnen stone code. Example: P28-NM55.
The distance that the workpiece is stroked beyond the end of the stone. This distance is generally one-third the length of the stone (or of the part, whichever is the shortest).
Rainbow (or bow)
Sometimes called camber or banana shape. A condition where a bore's diameter may be the same over its full length but whose axis or center-line is curved. Correction of rainbow by honing requires a mandrel in which the stone and guide show length is at least 1-1/2 times the length of the bore.
Example of rainbow
An enlargement of diameter at the bottom of a blind hole which makes it possible for the end of the honing stone to pass beyond the bottom end of the surface being hones.
Off-center rotation of the honing unit which causes eccentric motion of the workpiece.
Carbure de silicium
A man-made abrasive most often used for stock removal in materials such as cast iron, brass, bronze or aluminum. Also used for fine finishes in all materials. Designated by the letter "J" in the Sunnen stone code. Example: K12-J47.
A technique for honing short parts. Faces of the parts must be square with the bore prior to honing. A holding fixture is necessary for aligning and holding the parts on a common center.
Example of stacking
A bore condition where the diameter of a bore gradually increases from one end of the bore to the other.
Example of taper
Douille de dressage
A cylinder or workpiece whose purpose is to make the guide shoes and stone straight and parallel to each other, and radiused to the approximate diameter to be honed.
A longitudinal wave, series of waves or ripple in a bore surface.
Example of waviness

Honing Technical Guides

This repository of technical resources provides an in-depth exploration of various honing techniques and invaluable insights to those seeking to hone their craft.