CN201031737Y

CN201031737Y - Wear resistant hard chromium piston ring

Info

Publication number: CN201031737Y
Application number: CNU2007200391759U
Authority: CN
Inventors: 张新国
Original assignee: CSR Qishuyan Institute Co Ltd
Current assignee: CRRC Qishuyan Institute Co Ltd
Priority date: 2007-05-31
Filing date: 2007-05-31
Publication date: 2008-03-05
Anticipated expiration: 2017-05-31

Abstract

The utility model pertains to an internal-combustion engine piston ring, in particular to a wear-resistant hard chromium-coated piston ring. According to the technical proposal provided by the utility model, the wear-resistant hard chromium-coated piston ring includes a ring-shaped matrix with an opening. The utility model is characterized in that the external spherical surface of the ring-shaped matrix has at least two hard chromium coating layers and the hard chromium coating layer is provided with reticulated cracks for oil storage and lubrication. The utility model can improve the eccentric wear of the piston ring and the wear-resistant performance of the hard chromium coating layer, decrease the internal stress of the coating layer, increase the fatigue and fracture resistant performance of the piston ring and further extend the service life of the piston ring.

Description

A kind of wear-resisting hard chromium piston ring

Technical field

The utility model belongs to a kind of internal-combustion engine piston ring, particularly a kind of wear-resisting hard chromium piston ring.

Background technique

China railways internal combustion engine locomotive piston ring wear-resisting functions coating has only common electrical hard chromium plating layer at present, be that continuous electroplating is produced in the solution of trioxygen-containing chromium and sulfuric acid composition, be single layer structure, its hard chromium thickness is generally 0.10～0.35mm, composition is the chromium that is adsorbed with small amount of H, O, because the existence of H makes coating produce internal stress, makes hard chromium the netted microscopic crack of width less than 0.2 μ m occur.Hard chromium hardness is 800～1100HV0.1, has good abrasion resistance.Yet excessive because of local pressure through regular meeting during piston ring work, concentrated wear accelerates to produce the eccentric wear phenomenon.In addition, when heat load and/or mechanical load surpassed it and bear the limit, former common hard chromium greasy property can variation, easily produces adhesive wear in this case, even scuffing of cylinder bore.

Summary of the invention

The purpose of this utility model is to design a kind of wear-resisting hard chromium piston ring, to improve the eccentric wear phenomenon of piston ring, improve piston ring hard chromium friction and wear behavior, reduce the coating internal stress, improve piston ring fatigue crack-resistant performance, thus the working life of improving piston ring.

The technological scheme that provides according to the utility model, wear-resisting hard chromium piston ring comprises the annular matrix that has opening, it is characterized in that: the periphery at annular matrix has two-layer at least hard chromium, is distributed with on the described hard chromium to can be used for the lubricated pattern cracking of oil storage.

The width of the pattern cracking on the described hard chromium is 0.2～10 micron, and crack density is 40～150/millimeter.

The width of the pattern cracking on the preferred hard chromium is 0.5～5 micron, and crack density is 50～80/millimeter.

Excessive because of local pressure through regular meeting during piston ring work, concentrated wear is accelerated and generation eccentric wear phenomenon.Former common hard chromium causes insufficient strength because of excessive wear, influences the piston ring performance, even makes piston ring produce fracture;

Stratiform oil storage hard chromium piston ring of the present utility model owing to have multilayer oil storage crackle at the eccentric wear position, has increased lubricating ability, thereby can slow down wearing and tearing when eccentric wear takes place, and has prevented the over worn generation of piston ring, guarantees the usability of piston ring.

In piston ring/cylinder sleeve friction system, when heat load/mechanical load that piston ring bore is excessive, lubricating oil oil film on the cylinder bore wall is near disappearing, Frotteurism is semi-dry friction even dry friction, adhesive wear easily takes place in former common hard chromium, even scuffing of cylinder bore, and the lubricant oil of the storage in the piston ring coating pattern cracking of the present utility model can constantly add to cylinder bore wall this moment, carry out the rubbing surface oil film and repair, thereby avoid encircling adhesive wear even scuffing of cylinder bore with cylinder sleeve.

The utility model has the advantages that: because multilayer hard chromium with stratiform structure; And every layer is distributed with and can be used for the lubricated pattern cracking of oil storage; In piston ring/cylinder sleeve friction system, when piston ring scuffing the time, manifest the pattern cracking that stores lubricant oil, thereby the wearing and tearing that slow down the piston ring working surface have improved the usability of piston ring, have prolonged the working life of piston ring to following one deck.

Produce bigger internal stress owing to there is hydrogen to infiltrate electrodeposited coating when the common hard chrome of piston ring is electroplated, may produce stress cracking in the work, its crackle becomes tired source and causes fatigue fracture;

The piston ring hard chromium that the utility model provides is made up of multilayer, and every layer all has the destressing operation, thereby the common relatively hard chromium piston ring of its coating internal stress is little, thereby has improved the fatigue strength of piston ring, has strengthened piston ring fatigue crack-resistant performance.

Description of drawings

Fig. 1 is the structural representation of the utility model piston ring, and its periphery is the novel wear resistant hard chromium.

Fig. 2 is the A-A cross-sectional configuration schematic representation of Fig. 1.

Embodiment

As shown in the figure: wear-resisting hard chromium piston ring comprises the annular matrix 1 that has opening, at the periphery (with the face of cylinder body sliding contact) of annular matrix 1 two-layer at least hard chromium 2 is arranged, and is distributed with on the described hard chromium to can be used for the lubricated pattern cracking of oil storage.

During production: at first on piston ring matrix 1, electroplate one deck hard chrome, then by the microscopic crack on the materialization means expansions hard chromium of corrosion to 0.2～10 micron of institute's width that requires, this crackle reticulates distribution, density is 40～150/millimeter, the H that makes in the coating simultaneously to be contained partly discharges, the coating internal stress reduces, obtain individual layer crackle oil storage coating, the individual layer thickness of coating is not less than 0.015mm, in kind carry out the production of second layer individual layer crackle oil storage coating, by that analogy, reach desired thickness (Fig. 3) until coating.

The utlity model has following features:

(1) reduces the internal stress of coating, improved piston ring fatigue strength

When the micro-crack of expansion on the hard chromium, every layer of contained hydrogen partial of coating discharged, reduce The internal stress of every layer of hard chromium, thereby improved the fatigue strength of piston ring, it is disconnected to promote its antifatigue The fragility energy.

(2) the eccentric wear phenomenon of improvement piston ring

Piston ring when work local pressure is excessive, concentrated wear is accelerated and when producing eccentric wear, former common hard chrome Coating causes insufficient strength because of excessive wear, affects the piston ring performance, even produces fracture, and this practicality Multilayer oil storage crackle appears in novel stratiform oil storage hard chromium cladding piston ring at the eccentric wear position, slowed down wearing and tearing, Thereby prevented the over worn generation of piston ring, guaranteed the serviceability of piston ring.

(3) improve piston ring hard chromium friction and wear behavior, avoided adhesive wear even scuffing of cylinder bore

In piston ring/cylinder sleeve friction system, when the thermic load/mechanical load that bears when piston ring is excessive, Lubricating oil oil film on the cylinder bore wall approaches and disappears, and Frotteurism is semi-dry friction even dry friction. Former common Adhesive wear easily takes place in hard chromium, even scuffing of cylinder bore, and piston ring coating pattern cracking of the present utility model In lubricating oil this moment of storage can add to cylinder bore wall, carry out the rubbing surface oil film and repair, thereby can keep away Exempt to encircle adhesive wear even scuffing of cylinder bore with cylinder sleeve.

Claims

1. a wear-resisting hard chromium piston ring comprises the annular matrix that has opening, it is characterized in that: two-layer at least hard chromium is arranged on the surface of annular matrix, be distributed with on the described hard chromium and can be used for the lubricated pattern cracking of oil storage.

2. wear-resisting hard chromium piston ring according to claim 1 is characterized in that: the width of the pattern cracking on the hard chromium is 0.2～10 micron, and crack density is 40～150/millimeter.

3. wear-resisting hard chromium piston ring according to claim 1 and 2 is characterized in that: the width of the pattern cracking on the hard chromium is 0.5～5 micron, and crack density is 50～80/millimeter.