Piston ring types

THN Piston Rings typen 01 4

Piston rings play a very important part in internal combustion engines. They must absorb the combustion pressure, cool the piston, keep the oil in the crankcase and provide a film of oil on the cylinder wall. Most modern 4-stroke engines are usually fitted with three piston rings per cylinder. The first ring holds back the combustion gases. The second ring helps to hold back combustion gases and also scrapes the oil downward. The third ring holds the oil where it needs to be.

THN Piston Rings typen 01 4

Compression rings

Compression rings
TypeSection (click on the image to enlarge)Description
C1THN Type C1Rectangular compression ring
C2THN Type C2Taper faced compression ring
C3THN Type C3Internally beveled compression ring
C4THN Type C4Internally stepped compression ring
C5THN Type C5Ridge dodger ring
C6THN Type C6Keystone compression ring
C7THN Type C7Half-keystone compression ring
C8THN Type C8Taper faced scraper ring
C9THN Type C9Barrel faced compression ring
CLTHN Type CLL-ring

Scraper rings

Scraper rings
TypeSection (click on the image to enlarge)Description
S11Napier ring
S13Taper faced napier ring

Oil control rings

Oil control rings
TypeSection (click on the image to enlarge)Description
O21THN Type O21Oil control ring
O23THN Type O23Double-beveled oil control ring
O25THN Type O25Double-beveled oil control ring
WO21THN Type WO21Coil ring-loaded slotted oil control ring
WO23THN Type WO23Coil ring-loaded beveled-edge oil control ring
WO25THN Type WO25Coil ring-loaded beveled-edge oil control ring
3XOTHN Type 3XO3-piece oil control ring

Piston Ring Type Standards

Overview of standards used for the different piston ring types:

  • DIN 24910: Piston rings for industrial applications 18-1000mm
  • DIN 34110: Compression rings for industrial applications 18-1200mm
  • VDMA 24910: Piston rings with step cut for industrial applications 18-1000mm
  • DIN 70 910 to 70 916: Compression rings for motor vehicles 30-200mm
  • DIN 70 930: Compression rings for motor vehicles 30-200mm
  • DIN 70 946 to 70 948: Oil control rings for motor vehicles 30-200mm
  • ISO 6621 to 6624: Compression rings for internal combustion engines 30-200mm
  • ISO 6625 to 6627: Oil control rings for internal combustion engines 30-200mm

Need custom piston rings?

THN Customer Service Andre 01

In the case of very specific applications, the necessary piston rings may not be in stock. We also offer options for specially produced piston rings in any desired size and design. Delivery times are possible from 24 hours.

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