Project report for Piston Ring Manufacturing

The piston ring is one of the most important parts of the Deisel/Petrol engines. It is an open-ended ring that fits into a groove on the outer diameter of a piston in a reciprocating engine such as an internal combustion engine or steam engine. The principal function of the piston rings is to form a seal between the combustion chamber and the crankcase of the engine.  The goal is to prevent combustion gases from passing into the crankcase and oil from passing into the combustion chamber
The three main functions of piston rings in reciprocating engines are:
1.    Sealing the combustion/expansion chamber.
2.    Supporting heat transfer from the piston to the cylinder wall.
3.    Regulating engine oil consumption.
During the compression and power strokes, the compression ring seals the combustion gases and prevents blow-by. Although blow-by is not completely eliminated it is kept to an acceptable limit.  During the compression and exhaust strokes, the cylinder walls are lubricated with oil by a throw off from the connecting rod bearings.  Excess oil is wiped off by the piston rings.  Not only does the oil ring have the responsibility of wiping the excess oil off the cylinder walls, but the job is also shared by all of the rings, leaving a fine layer of oil on the wall to provide lubrication for the following ring.  As rings wear, the ability to perform these functions is decreased resulting in oil consumption and blow-by.  When this happens it is time for a new set of rings.

Piston rings are generally made up of cast iron. The blanks of cast rings of required size and desired properties are procured from the local foundries. After that blanks are cleaned and get ground. Then the blanks are undergone through various processes like facing, rough diameter, rough bore, finish diameter & finish bore. The rings are generally machined to the required shape by means of  turning, a process in which the ring blank, already axially ground, is copy turned on the inside and outside diameters. After a segment equivalent to the free gap is cut from the ring it assumes the free shape that will give it the required radial pressure distribution when fitted into the cylinder..

The materials used to make Piston Rings are one of the most critical factors in its performance.

Listed below are some of today's common material used in manufacturing of piston rings and metallic seals:

    Cast iron
    Cast iron alloyed for piston rings
    Nodular cast iron alloyed for piston rings
    Bronze
    Aluminum Bronze
    Phosphor Bronze
    Steel
    Stainless Steels for use in high temperature

QUALITY CONTROL
The procured blanks castings should be checked very carefully as per given requirement (size,grade etc). This is the very first step in quality control.The product should be monitored after completion of each stage so that chance of rejection at the end is eleminated. Piston rings should be manufactured as per IS : 5791-1971 & IS: 8422 for IC engines.The entire operation of surface treatment/ coating should be closely controlled. For the inspection process proper callibarated gauges should be used.

POLLUTION CONTROL
As this unit doesnot comes under heavy polluted industry, although No Objection Certificate from pollution control board should be taken.

Piston ring is the one of the most replaceble part of the diesel/petrol engines.It has great demand in the replaceble market as well as in new engines market.For the last few years there is noticeble increase in the automobile industry, which is the vast market for it. Piston rings are not only used in the automobile industry but also used in :
•    Railway Engines
•    Compressors
•    Steam Hammers
•    Cars
•    Retaining Rings
•    Pumps
•    Industrial Applications
•    Cranes
•    Gearboxes
So, by maintaining quality  and using proper marketting techniques there is alwayes a great market of  this product.