RU2249506C2 - Method to increase corrosion resistance of rolling stock wheelsets - Google Patents

Abstract

FIELD: railway transport; rolling stock.

SUBSTANCE: proposed method includes cleaning of wheels by blasting and protection of cleaned surface form corrosion combined with cleaning. Cleaning is done using grains of water or dry ice, and corrosion protection is carried out by delivering liquid nitrogen to wheels surface to form nitrated layer.

EFFECT: increased capacity at anticorrosive treatment of wheelsets.

Description

The invention relates to methods for protecting against corrosion of surfaces of metal objects and, in particular, to the corrosion resistance of wheelsets of railway rolling stock.

A known method of increasing the corrosion resistance of wheelsets of a rolling stock, including preparing the surfaces of the axle and wheels of the wheelsets and applying corrosion-resistant paint to them (1).

However, the used paints do not protect the wheelset from corrosion for a period of 1-3 years. In addition, during operation, corrosion products 1-2 mm thick are deposited on it, which makes it difficult to perform a flaw inspection of a wheel pair. Corrosion products and paint adhere so firmly to the substrate that special washers have been created to remove them. However, the washing does not allow to remove corrosion deposits and, especially, paint. They are removed manually.

A known method of repairing wheelsets, including defectoscopic preparation of the surfaces of the wheelset, consisting of cleaning it by washing or mechanically, inspection of the flaw and performing a paint operation that increases the corrosion resistance of the wheelset (2).

However, the cleaning technology requires capital and large operating costs associated with the consumption of electricity, soda, heat. And the quality of inspection is poor.

The proposed method of increasing the corrosion resistance of the wheelsets of the rolling stock is that the preparation of the surfaces of the axle and wheels of the wheelsets, consisting of the operation of cleaning them and the operation of protecting the surfaces from corrosion, is combined by performing the cleaning and corrosion protection operation simultaneously.

Also, the difference is that water ice granules are obtained by spraying water in a mass of liquid nitrogen, and at the same time as cleaning due to the jet-abrasive effect, corrosion protection is carried out with liquid nitrogen located on the surface of water ice granules.

The difference is also that a vacuum is created by compressed air and, due to the vacuum, granules of water ice are ejected simultaneously with liquid nitrogen, and the resulting mixture of granules with liquid nitrogen is fed to the surface of the wheelset.

Also, the difference is that the removed corrosion products and paints are collected in a dust-free way, or in a special collector, and liquid nitrogen evaporates into the atmosphere.

Experience 1. In the depot removed from the passenger car, the wheelset without washing is subjected to blasting, while nitriding with liquid nitrogen on the outer surface. Water is sprayed in a mass of liquid nitrogen to obtain granules of 3-5 mm in size. The granules thus obtained were poured into a 60 liter feed hopper. Granules from the hopper due to deep ejection (vacuum) were fed with high pressure air into a booster-ejector device (REU).

At the exit from the REU, an air flow with granules was obtained and directed to the axis of the wheelset and sequentially on the surface of its disks.

The air pressure was 5 atm. The consumption of granules per wheel pair amounted to 30 kg, nitrogen consumption of 15 liters.

After processing for 6 minutes without interruption, the steam was subjected to flaw inspection, i.e. at the same time as cleaning, they reached the requirements of the instructions.

The above sharply reduces the set of equipment for repairing a wheelset. Previously, washing was carried out for 15-20 minutes, then manual cleaning of the surface of the axle of the wheelset was carried out for 5-10 minutes, then 6-8 hours were expected (cooling period of the pair) for inspection.

The productivity of wheelset repair workshops due to the introduction of this method will increase by 5 times, the cost of paint and the operation of painting will be reduced, and corrosion protection is achieved by the action of liquid nitrogen on the surface of the wheelset.

Based on this method, a semi-automatic complex of jet preparation of wheel sets is created during repair in the depot of the industry.

Experience 2. Repeated the processing as in claim 1, additionally supplying liquid nitrogen with a jet moving directly behind the nozzle of the REU. The consumption of ice granules is the same; nitrogen consumption was 25 liters per wheel pair.

Sources taken into account

1. Directory of the railroad. - M., 1950.

2. The technological process of repairing wheelsets. - M., VNIIZHT, 1975.

Claims (1)

A method of increasing the corrosion resistance of wheelsets of a rolling stock, including cleaning the wheelset by a jet method and protecting the cleaned surfaces from corrosion, characterized in that the cleaning and corrosion protection operations are combined, while cleaning is carried out with ice granules, which are obtained by spraying water in a mass of liquid nitrogen and using compressed air and the vacuum created by it in the accelerator-ejector device, the obtained granules of water ice are ejected simultaneously with liquid nitrogen and the resulting mixture is fed to the surface st wheelset reaching the nitrided layer.