Various scraper rings are used in light-vehicle gasoline, andlight-vehicle and truck diesel engines. They are occasionally usedin the compressors of commercial vehicle air-brake systems. Scraperrings assist the upper compression ring in sealing the combustionchamber from the crankcase. Scraper rings scrape, control and storeoil, which is between the upper compression ring and the scraperring.

Oil-Control Rings

Oil-control rings are used in light-vehicle gasoline engines(two- or three-piece), light-vehicle diesel engines (two-piece),and truck diesel engines (two-piece). The main function of therings in the bottom piston groove is to scrape oil from thecylinder wall, meaning oil-control rings play a major part inregulating an engine’s oil consumption.

Compression Rings

Gray castiron and steel piston rings are manufactured in differentprocesses. At JPPR, gray iron piston rings are cast as individualrings in a noncircular shape. The rings are generally machined tothe required shape by means of double-cam turning, a process inwhich the ring blank, already axially ground, is copy-turnedsimultaneously on the inside and outside diameters.

Steel piston rings are made from a profiled wire. The rings arecoiled into a circular shape, then the gap is cut out. Thenecessary shape is obtained using a heat-treatment process in whichthe rings are mounted onto an arbor appropriately designed toimpart the required radial pressure distribution.

Scraper Rings

The ring step is produced in a rectangular or undercut (Napier)design. The advantage of the undercut step is that when the ringtwists, a sharp downward scraping edge will still be available toconduct the oil quickly from the ring’s outer edge into the step’sreservoir. This prevents oil from gathering at the scraping edgeand diminishing the scraping effect.

 Oil-Control Rings

JPPR  commonly produces fivedifferent types of two-piece oil-control ring bodies. Variations onring land geometry and running face coating give many options foroil consumption and wear performance.

 Three fundamentalexpander-spacer styles have been established for oil-control ringson the world market. When made from a nitridable steel, nitridingcan provide effective protection against secondary wear.

Packing info asfollows: