JPS6046185B2 - Bearing oil groove machining method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for machining oil grooves in metal journal bearings, thrust bearings, and rocking bearings.

Conventional bearings are shown in FIGS. 1 to 3.

1 is a journal bearing, 2 is a thrust bearing, and 3 is a swing bearing.

Therefore, each bearing 1 to 3 has its bearing surface portion 1a, 2a, 3a.
Oil grooves lb, 2b, and 3b are cut by machining.

According to the manufacturing method of the oil grooves 1b, 2b, and 3b that require cutting, deburring, honing for cleaning the cutting part, etc.
High-precision machining using expensive machine tools is required, and there is a risk of galling due to cutting residue. Also, because it is machined, it is difficult to process thin oil grooves on small items. The present invention has been made to improve these drawbacks.

In other words, a corrosive liquid selectively corrodes only the grain boundaries of the metal that make up the sliding surfaces of metal journal bearings, thrust bearings, rocking bearings, etc., forming intergranular corrosion oil grooves. It's a very important thing. The features of the present invention will be explained below based on an embodiment shown in FIG.

4 indicates a journal bearing made of SUS3■ (stainless steel).

This bearing was heated in a heating furnace at 8000C for 1 hour,
After slow cooling, the area other than the sliding surface 4a of the bearing is masked with a coating 6, and this is soaked in a ferric chloride solution kept at 30°C.
After being immersed for 5 to 5 minutes to corrode the sliding surface 4a of the bearing and selectively corrode only the grain boundaries of the metal to form intergranular corrosion grooves 4b, this is washed and dried. These intergranular corrosion grooves are fine and have very good oil retention, so
This will be the oil groove.

A wear test was conducted on several bearings with oil grooves of various depths that had caused intergranular corrosion using this method, after immersing the bearings in oil and wiping off the oil completely. The relationship between the amount of wear and the depth of the oil groove was as shown in Figure 5.

That is, due to the presence of the intergranular corrosion oil grooves 4b, the amount of wear is rapidly reduced, and the effect of the intergranular corrosion oil grooves is large.

Further, the amount of wear is small when the depth of the intergranular corrosion oil groove is between 0.5 and 2 Tnm, and the amount of wear increases even when the oil groove is shallower or deeper than that.

According to the present invention, the oil grooves are machined by corroding only the grain boundaries of the metal constituting the sliding surface with a corrosive liquid that selectively corrodes them to form grain boundary corrosion oil grooves. In comparison, it has superior effects such as superior productivity, inexpensive equipment, and no galling caused by cutting residue.

According to this embodiment, since intergranular corrosion oil grooves are formed on the heat-treated bearing sliding surface, intergranular corrosion is promoted and productivity is further improved.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a journal bearing with a conventional machined oil groove, Fig. 2 is a sectional view of a thrust bearing with a conventional machined oil groove, and Fig. 3 is a sectional view of a conventional journal bearing with a machined oil groove. FIG. 4 is a cross-sectional view of the thrust bearing of the present invention, and FIG. 5 is a characteristic diagram of the depth of intergranular corrosion oil grooves and amount of wear of the same bearing. 1...Journal bearing with machined oil grooves,
1a...Journal bearing sliding surface, 1b...Journal bearing machined oil groove, 2...Thrust bearing, 2a...Thrust bearing sliding surface, 2b...・
... Thrust bearing machined oil groove, 3 ... Rocking bearing, 3a ... Rocking bearing sliding surface, 3b ...
- Rocking bearing machined oil groove, 4...Journal bearing having intergranular corrosion oil groove of the present invention, 4a...Journal bearing sliding surface, 4b...Grain boundary Corrosion oil groove.

Claims (1)

[Claims] 1. Corrosion with a corrosive solution that selectively corrodes only the crystal grain boundaries of the metal that constitutes the sliding surface of a bearing, such as a metal journal bearing, thrust bearing, or rocking bearing, to destroy the grain boundaries. A method for machining oil grooves in a bearing, characterized by forming corrosive oil grooves. 2. The method for machining oil grooves in a bearing according to claim 1, wherein intergranular corrosion oil grooves are formed after heat treatment is applied to the sliding surface of the bearing. 3. The method for machining oil grooves in a bearing according to claim 1, wherein the depth of the intergranular corrosion oil grooves is 0.05 to 2 mm.