JPS59120385A - Mechanical seal ring and its production - Google Patents

Abstract

PURPOSE:To obtain easily a product which is securely joined with a sintered hard alloy having a min. required thickness by joining a torus-shaped sintered hard alloy layer to the end face of a torus-shaped base material formed of a Ti-Mo sintered alloy via a Cu-Ti alloy layer diffused to both layers. CONSTITUTION:A sintered body of a Ti-Mo alloy is made and the inside and outside surfaces thereof as well as the end face are ground to make a torus- shaped base material 1. A torus-shaped copper sheet is placed on the end face and a sintered hard alloy plate 3 having a preliminarily ground end face is placed thereon, and while load is exerted thereon in a vacuum, the assembly is heated and held. Then a Cu-Ti eutectic alloy layer 2 diffuses into the material 1 and the plate 3 and the material 1 is metallurgically and securely joined to the plate 3 via the layer 2. The plate 3 is kept free from undue compressive stress unlike in the case of assembling by a shrinkage fitting method and therefore the plate 3 is required to have a min. required thickness.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mechanical seal ring and a method for manufacturing the same.

(1) There are many types of mechanical seal rings, but the materials usually used include plastic, hard rubber, carbon, Hastelloy, Ceramics, and cemented carbide. Among these, mechanical seal rings made of cemented carbide have excellent properties such as wear resistance and toughness, and are therefore widely used in combination with rings made of carbon.

Iron-based alloys are usually used as the platinum for the cemented carbide mechanical seal rings mentioned above, but since this iron-based alloy base metal has insufficient corrosion resistance in various corrosive environments, Ti alloys with high corrosion resistance are used as the base metal. It is sometimes used as a material for gold. In order to attach cemented carbide to a T1 alloy base metal, generally a Ti alloy melt is machined.A method of shrink fitting a cemented carbide ring onto a circular ring shaped base metal. However, in order to achieve an accurate shrink-fitting condition, T
1 Alloy base metal and cemented carbide ring both have extremely strict dimensions.T1 alloy is prone to oxidation due to heating, so special means must be used for heating during shrink fitting (2). Furthermore, there are various problems in that the cemented carbide ring is subjected to a considerable compressive stress after being shrink-fitted, and the cemented carbide ring must be made thicker than necessary in order to withstand the compressive stress.

- Ti-
Mo-based alloys have the property that when they are produced as melted materials, they are highly segregated and have poor machinability thereafter.

The present invention takes into consideration the conditions mentioned above, and aims to provide a mechanical rail ring that is particularly resistant to reducing acids such as hydrochloric acid and sulfuric acid and is highly edible, and a method for producing the same.
The gist is that a circular cemented carbide layer is firmly adhered to the end face of a circular base material made of a Ti-Mo based sintered alloy through a Cu-Ti eutectic alloy layer, and the above-mentioned Cu-Ti eutectic alloy A mechanical seal ring characterized in that it is in a mutually diffused state with both the Ti-No-based sintered alloy and the cemented carbide, and the end face of the circular base material made of the Ti-Mo-based sintered alloy and the circular A Cu or Cu-based alloy thin plate is placed between the end face of a ring-shaped cemented carbide plate, heated and held in a non-oxidizing atmosphere while applying a load, and is bonded by diffusion bonding)+Ti-Mo based sintered bonding. This method of manufacturing a mechanical seal ring is characterized by firmly joining a gold base material, a Cu or Cu-based alloy thin plate, and a cemented carbide plate.

The Ti-No based sintered alloy used in the present invention is
It usually contains 5 to 35% by weight of Mo, and the Cu-based alloys include Cu-Ni, Cu-Ni-P +Cu
-Ag.

Cu--AI etc. shall be used.

Cemented carbide is mainly composed of 11C, binders such as Co and Ni, and TiC, TaC, MozC as necessary.
, VC, etc. in a range of about 5% by weight or less.

The present invention will be described in detail below with reference to examples thereof.

<Example 1> Seven Ti powder powders of 100 mesh or less and three No powder powders with a diameter of 5 μm were added to 2 wt. Obtained. This mixed powder was heated at a pressure of 2 tons/c+/ with an outer diameter of 711 mp, an inner diameter of $ 4511111, and a thickness of 4 (lnw).
Compression molding 17 in a circular ring shape, in vacuum (10"" torr)
) After pre-sintering at 500°C, sintering in high vacuum (10-
The material was sintered at 1450° C. for 2 hours in a small torr to obtain a sintered body with a theoretical density of about 97%. The inner and outer surfaces and end surfaces of this sintered body were ground, and a 0.2 mg thick layer was placed on the end surface of a circular base material obtained by grinding the inner and outer surfaces and end surfaces.
A + circular ring-shaped Cu plate was placed on top of which the end surface was ground in advance, with an outer diameter of ≠69+na+ and an inner diameter of 1511II+.

Cemented carbide plate with thickness 311I+ (IIC- 6.5C
o) and 30g in vacuum (10-+torr)
A mechanical seal ring as shown in FIG. 1 was obtained by holding at 900° C. for 1 hour while applying a load of /cd. In FIG. 1, (1) indicates that the Ti--Mo alloy base material (2) is the Cu--Ti eutectic alloy layer (3) (the cemented carbide layer).

The structural photographs and EPMA images of the joints of the products obtained as described above are shown in FIGS. 2 to 7. That is, Fig. 2 is an electron micrograph of the structure of the joint, and W, Co, Ti#No, and Cu at the same location shown in this photo.
(5) Figures 3 to 7 show the respective characteristic X-ray images of Ti-M.
o When the Cu plate placed between the base material and the cemented carbide plate is heated and held, it diffuses into T1 and Cu-
It can be seen that the alloy is a Ti eutectic alloy, and that considerable amounts of W, Co, and Mo have each been diffused into the Cu-Ti eutectic alloy.

The shear strength of the product obtained in Example 1 was determined at the Cu-Ti eutectic alloy layer, and the result was 18 kg/
It was “w”.

Next, as shown in Fig. 8, the mechanical seal ring (1F) is placed between two suppression plates (41, (4)) with rubber backings (5), (5) on both sides, and firmly secured with bolts (6). For tightening, compressed air was injected and the pressure in the internal space (8) of the mechanical seal ring was checked using the pressure gauge (7), and the ring was immersed in water to measure the pressure leakage. As a result, the gauge pressure was 8. No air leakage was observed even after 30 minutes at 5 kg/cj.

Also, cut out the mechanical seal ring and heat it at 50°C for 10 minutes.
% hydrochloric acid and 10% sulfuric acid at 50° C. for 188 hours, and the state of the cross section of the joint was observed, no corrosion was found and the corrosion resistance was sufficient.

<Example 2> Using 85% by weight of TL powder of 100 mesh or less and 15% by weight of No powder with an average particle size of 5 μm, a circular base material with a theoretical density of about 97% was prepared in the same manner as in Example 1 above. I got it.

On this circular base material, a circular Cu plate with a thickness of 0.2s+s+ is placed.
A mechanical seal ring was obtained by placing a Ni alloy plate (Cu -5,5Ni) and a cemented carbide plate with an outer diameter of 69 rv+, an inner diameter of 151 nm, and a thickness of 311 Il whose end surfaces had been ground in advance. .

The shear strength of the product obtained in Example 2 was determined at the Cu-Ti eutectic alloy layer, and the result was 15 kg.
/It was the second time.

An air leak test similar to that described in Example 1 was conducted on this product, and the results showed no air leaks even after 30 minutes at a gauge pressure of 8.5 kg/cd (also, in the corrosion resistance test of the joints) was not corroded in any way.

In addition to Examples 1 and 2 described above, we conducted experiments with various conditions (7) for heating and holding, and found that when the atmosphere is in the air, the Ti-No base material is oxidized, which is preferable. In terms of vacuum conditions, the higher the vacuum, the stronger the bond.
It was confirmed that if the bonding strength was changed from an argon atmosphere, almost the same bonding strength as in an IP'torr vacuum could be obtained.

As described above, according to the present invention, a Ti=No alloy and a cemented carbide, which are highly resistant to corrosion against reducing acids such as hydrochloric acid and sulfuric acid, are interposed between a Cu-T1 eutectic alloy layer. The bonding strength is high because it is strongly metallurgically bonded through the base material and the cemented carbide. As a result, it is formed by the Cu-Ti eutectic alloy, so it is impossible to apply unreasonable compressive stress to the cemented carbide, as in the case of the burn-out method, for example. Therefore, cemented carbide has the advantage that it only needs to be as thick as possible.

In the present invention, since the Ti-No alloy base material is obtained by sintering rather than from melted material, there is no non-uniformity in the structure due to sintering (8), and the subsequent processing steps are easy. It is simple, and the material yield is significantly higher than that obtained by cutting out a circular base material from melted lumber, so it is also effective in terms of economic effects.

[Brief explanation of the drawing]

Fig. 1 is an explanatory view of the rod part 1 of the mechanical seal ring obtained in Example 1 of the present invention, and Fig. 2 is an electronic Ijl telescopic otoscopic photograph of the same joint part. Figs. 3 to 7 are W of the same joint part, respectively. ,
EP showing characteristic X-ray images of Co, Ti, No, Cu
MA image, FIG. 8 is an explanatory diagram showing an air leak test of a mechanical seal ring. In the figure, (1) + Ti-Mo alloy base material + 21 + Cu-Ti eutectic alloy layer (3): Cemented carbide layer Patent applicant Nippon Tungsten Co., Ltd. Agent Yoshi Ari
Noriharu (9) Figure 1 Figure 8 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure Kazuo Wakasugi, Commissioner of the Patent Office 1, Indication of the case 1982 Patent Application No. 232153 2. Name of the invention Mechanical seal ring and its manufacturing method 4. Relationship with the case of the person making the amendment Patent Applicant Address Name F1 Hon Tungsten Co., Ltd. 4 Agent address 1-110-27 Hakataekigashi Higashi, Hakata-ku, Fukuoka City full name
+8429+ Patent attorney Noriharu Jiyoshi 5, Amendment order with H, Showa month, E16, Subject of amendment Specification 7, Contents of amendment (1), ["AI, etc."] on page 4, line 12 of the specification, r Al, Cu-Ti, etc.". (2) Insert "[or binderless cemented carbide]" after "contained" on page 4, line 15 of the specification. (3) Correct "blasting machine" in the second line from the bottom of page 4 of the specification to "(Lightning crusher j). (4) 12-fold rectangle - Tricrane in the bottom line of page 4 of specification Correct "45 iunJ" in the third line of page 5 of the specification to "57 mmJ." (6), Page 6 of the specification, line 3. rMo base material in the second row
Corrected to ``Ho thread base material''. (1) -,,,,,,443-1

Claims (1)

[Claims] 1. A circular cemented carbide layer is firmly adhered to the end face of a circular base material made of a Ti-Mo based sintered alloy through a Cu-Ti eutectic alloy layer, and the above-mentioned Cu -Ti eutectic alloy is Ti-
A mechanical seal ring characterized by being in a mutually diffused state with both a Mo-based sintered alloy and a cemented carbide. 2. A thin U- or Cu-based alloy plate is placed between the end face of the circular base material made of Ti-Mo based sintered alloy and the end face of the circular cemented carbide plate, and a non-oxidizing atmosphere is provided. Manufacture of a mechanical seal ring characterized by firmly joining a Ti-Mo based sintered alloy base material, a Cu or Cu-based alloy thin plate, and a cemented carbide plate by heating and holding while applying a load in a chamber and by diffusion bonding. Method.