RIKEN Piston Ring

Product Made in Japan
Manufacturer: RIKEN
Model: RIKEN Piston Ring

Specifications

Name of each part of the piston ring

Nomenclature and symbols under free state

Nomenclature of edges, inside and peripheral surfaces, and side face

1) Cross-section configuration

	Rectangular ring
	Keystone ring
	Half keystone ring
	Scraper ring (stepped)
	Napier ring (under-cut stepped)
	Slotted oil control ring
	Bevelled-edge oil control ring
	Double-bevelled oil control ring
	Coil spring loaded oil control ring
	Coil spring loaded Bevelled-edge oil control ring
	Coil spring loaded double Bevelled-edge oil control ring
	Expander / segment oil control ring

2) Face configuration

	Straight-faced
	Barrel-faced
	Taper-faced

3) Edge configurations

	Internal bevel top (positive twist type)
	Internal step top (positive twist type)
	Internal bevel bottom (negative twist type)
	Internal step bottom (negative twist type)
	Inside edges chamfered
	Outside edges chamfered
	Inside and outside edges chamfered

4) Coating configurations

	Uncoated
	Coated fully faced
	Coated semi-inlaid
	Coated inlaid

5) Joint configuration Joint configuration

	Joint (straight)
	Oblique joint (angle)
	Stepped joint (angle)
	Joint with side notch
	Joint with internal notch

MARTERIAL

● Steel
RIK-SP is a steel material selected and refined as a material suitable for piston rings. It is used for pressure rings of compact high-speed engines and side rails of combination oil rings.
It is also used for high performance oil ring for diesel “Diesel Vent – M”.
RIK-SS is superior in formability, spring characteristics, heat resistant permeability, and is selected and used as a spacer material for a combination oil ring “Rick vent” according to a wide range of engine specifications.

× 400%

STEEL
RIK SP-5

● HI-RIK
HI-RIK is a high elastic material with a standard modulus of elasticity of 147 ~ 167 GPa and close to 196 GPa of Steel. This is because the graphite shape which largely influences the mechanical properties of cast iron is composed of spheroidal graphite cast iron and tempered graphite with less notching effects and dense perlite and acicular.
It is remarkably superior in wear resistance and ranked highest among existing cast irons. HIGHLIC is suitable for pressure rings and oiling rings that require high elastic modulus and break resistance especially in automobiles, ships, construction machinery, aircraft, etc.

× 400%

HI-RIK
RIK-20A

● RIK-S
RIK-S is a tough cast iron with superior physical properties, without adding alloying elements by special refining technology, moderate elasticity and hardness are obtained moderately, and conformability is also good Well, resistance to impact is also relatively good.

× 400%

RIK-S
RIK-42A

● Rik-A
This Rik-A is a cast iron in which fine graphite is uniformly distributed in the bainite matrix, and special elements such as nickel, molybdenum, vanadium and chromium are added in appropriate amounts.
Therefore, the hardness of the base is about 500 HmV, which is excellent in abrasion resistance, cut resistance, heat resistance, etc.
It also has a relatively high modulus of elasticity and hardness, it is a material that is resistant to friction, striking, abrasion and breakage.Therefore, it is suitable for piston ring material of harsh use conditions such as TOP ring of high speed / high power engine and construction machine.

× 400%

RIK-A RIK-A
11

● RIK – DITE
RIK – DITE is phosphorus, vanadium, composite carbide in the pearlite base is uniformly distributed with graphite having a self-lubricating by addition of titanium. Special elements such as phosphorus, vanadium, titanium and chromium become complex carbides and become hard spots during friction and reduce wear.
Although this material is suitable for general engines such as automobiles, ships, agricultural machines, etc., it has good correlation with cylinder material having complex carbide by vanadium and other elements, and demonstrates excellent durability.

× 400%

RIK – DITE
RIK – 30

● Rik
This material is particularly suitable for rings for hydraulic cylinders that are easily damaged and for metallic packing materials for ships, the amount of graphite rich in oil retention and self lubricity is larger than other materials and damages the mating material Easy stdite amount is reduced as much as possible.

× 400%

RIK
RIK – 50

Surface modification

A. Hard Chrome Plating (Cr)

Hard chrome plating has excellent characteristics combining the properties inherent in metallic chromium and the properties unique to electrodeposits. Its main features are:

1.	The hardness is very high. Vickers hardness 800 to 1100 (ordinary cast iron 220 to 270)
2.	The melting point is high. About 1800 ° C (normal cast iron: about 1200 ° C)
3.	Excellent thermal conductivity and corrosion resistance.
4.	Low wear coefficient and excellent wear resistance.

Because it retains the characteristics such as, it is very effective as a wear prevention measure of the piston ring.
It goes without saying that the development of this hard chromium plating caused the engine performance to make a big leap. For this reason, it is used not only for piston rings for lawn mowers, two wheels, and passenger cars, but also for bus trucks. Also, the high pressure compressor is subjected to chrome plating that is porous with oil retention.

● Wear resistance of hard chromium plating

The data on the right is the results of friction and wear test of high grade cast iron ring material and hard chromium plating. Normal cast iron is used for the mating material. I think that it can be clearly seen from this data that hard chrome plating is hard to wear about 7 to 8 times of high grade cast iron. Although this also changes greatly depending on the wear condition, almost the same wear result can be obtained even if it is assembled to gasoline · diesel engine under normal operation.

B. Nitriding (GN) Due to the
recent high-speed and high-load operation of automotive internal combustion engines, extremely high wear resistance is required for piston rings. The GN piston ring was developed based on these requirements.
GN piston ring is made of RIK-SP-3 (17% Cr martensitic stainless steel containing Mo and V as alloying elements) as a base material, and gas nitriding is applied to this.
Therefore, the surface of the ring has an extremely hard nitrided layer made of nitrides of Cr and Fe, and this layer exhibits excellent abrasion resistance and scuffing resistance.
● Features

1.	Because it forms an extremely hard surface layer, it has excellent abrasion resistance.
2.	It has excellent scuff resistance against FC cylinder liner material.
3.	It has high corrosion resistance abrasion resistance.
4.	It has excellent wear resistance on the upper and lower surfaces.