Grey cast iron and steel piston rings are manufactured in different processes. Piston ring materials are subject to a complex stressing system under mainly . Surface Treatments. The following surface treatments for piston rings are.

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However, no harm will be done if the gaps temporarily align in service. Additionally, thermophysical uandbook such as thermal conductivity and thermal expansion are a major factor in the performance of piston rings.

The wear resistance derives from finely distributed chromium carbides of the type M 23 C 6 and M 7 C 3 embedded in the tempered martensite matrix. Too large a gap may give unacceptable compression and levels ahndbook blow-by gases or oil consumption. Increasingly, corrosion resistance and resistance to microwelding are properties that also determine the characteristics of piston ring materials. It soon replaced the hemp packing federal mogul piston ring handbook used in steam engines.


Piston Ring Handbook Piston Ring Materials Piston ring materials are subject to a complex stressing system under mainly dynamic mechanical and tribological loads. Unalloyed grey cast iron is used for 2-piece oil rings in the 3rd groove.

The steels mentioned are used chiefly as compression ring materials for gasoline engines and truck diesel engines as well as for the steel rails and expander-spacers of oil control rings and for 2-piece profiled steel oil ring s.

At least two piston rings are found on most piston and cylinder combinations. Piston ring materials are subject to a complex stressing system under mainly dynamic mechanical and tribological loads.

The gap is cut out in a step between O. Automobile emissions control Catalytic converter Diesel particulate filter Exhaust manifold Glasspack Muffler.

These challenges are met by the use of high- chromium alloyed steels and spring steel s. Aircraft piston engine components, systems and terminology.

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Besides using double cam turningring blanks can also be shaped by machining the inside and outside diameters separately. The rings are generally machined to the required shape by means of double cam turninga process in which the ring blank, already axial ly ground, is copy turned simultaneously on the inside and outside diameters.

This involves cam turning the outside diameter of the noncircular blank and machining the inside diameter with the ring in the compressed state. The necessary shape is obtained using a heat treatment process in which the rings are mounted onto an arbor appropriately designed to impart the required radial pressure distribution.

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. Piston rings have been an area of considerable focus and development for internal combustion engines. Heat forming as a means of shaping piston rings should be mentioned to complete the range of options, but this process is seldom used.

For enhanced scuff resistance and further improved wear, most modern diesel engines have top rings coated with a modified chromium coating known as CKS [6] or GDC, [6] a patent coating from Goetze which has aluminium oxide or diamond particles respectively included in the chrome surface. Besides having a high bending strength and modulus of elasticityan increased hardness of to HB is produced in order to obtain the required wear resistance in the uncoated condition.

There are some taper-faced top rings as well, and on some old engines simple plain-faced rings were used. Rings are not a very expensive part, but fitting new ones is very costly on most engines.

Ring materials are selected from cast irons and steels according to the stated stresses and their use as compression or oil control rings.


To minimize this, they are made of wear-resistant materials, fedderal as cast iron and steel, and are coated or treated to enhance the wear resistance. Components Propeller governor Propeller speed reduction unit Spinner. This material is characterized by a high bending strength of min.

Besides steel materialsthe grey flake graphite or ductile nodular graphite cast irons shown in Table 1 are used in a non heat-treated condition or hardened and tempered. However, piston rings can be made from a federal mogul piston ring handbook variety of irons and steels with very different coefficients of expansion.

Piston Ring Handbook

At the limits of piston movement, the ring stops and reverses direction. Rings binding in the piston, usually due to a build-up of either combustion products or a breakdown of the lubricating oil, is a common cause of failure, especially for diesel engines.

Piston rings are subject to wear as they move up and down the cylinder bore due to their own inherent load and due to the gas load acting on the ring. The demand for high wear strength is also met by the use of a tempered, alloyed cast iron GOE Electric Fuel Pumps Replacing Mechanical.

Piston Ring Handbook Piston Ring Manufacture Grey cast iron and steel piston rings are manufacture d in different processes. This page was last edited on 18 Marchat Typically, top ring and oil control rings will be coated with chromium[6] or Nitrided[7] possibly plasma sprayed [8] or have a PVD [9] ceramic coating. The greater durability under increased stresses is demonstrated by the improved fatigue strength manifested as form stability, as shown in Fig.