JPS5926930A - Molybdenum electrode structure and its manufacture - Google Patents

Abstract

PURPOSE:To eliminate the generation of defective Mo electrode structure caused by the defect in its connecting part, by attaching a male or female screw at one end of an Mo electrode for glass smelting, and connecting another electrode with the screws interposing Mo paste between the connecting faces. CONSTITUTION:A male screw is attached to one end 2 of an Mo electrode rod 1, and a female screw to the other end 5 thereof. The contacting surface 4, 7 to be connected with another electrode rod is formed to a taper (theta) of 45 deg.. When the electrode rod is exhausted, the surface of the connecting face of the electrode is coated uniformly with Mo paste, the screw is engaged with the screw of the new electrode rod, and the rods are tightened firmly to obtain an electrode structure.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an electrode assembly made of molybdenum and used for glass melting, and a method for manufacturing the same.

[Technical background of the invention]

Conventionally, heavy oil or coal gas has been mainly used as a heat source for glass melting, but molybdenum rods have been used as heat sources.

Recently, electric melting using a self-resistance heating method using a plate or the like as an electrode has been increasingly used in combination. This electric melting method has various advantages as follows. In other words, when combined with electric melting, production volume can be greatly increased in the same kiln, the size of the kiln can be made smaller to produce the same amount of glass, and the quality of glass can be improved by creating a uniform temperature distribution throughout the kiln. It is very economical due to its high thermal efficiency, and it is also easy to control temperature and can be automatically controlled.

Electrode rods made of molybdenum are used as electrodes in electric melting, which allows for excellent glass melting.

The reason for this is that molybdenum electrode rods have good mechanical and thermal properties, do not become colored even when melted into glass, and are compatible with glass, making them extremely suitable as high-temperature electrodes for glass melting.

In order to install a molybdenum electrode rod into a glass melting kiln, it is charged horizontally or vertically from an inorganic material, and its configuration is determined appropriately depending on the amount of glass melted and the structure of the kiln. The electrodes used are of various shapes.

[Problems with background technology]

Molybdenum electrode rods used in such glass melting furnaces are used in molten glass at high temperatures, so they wear out over time, and it is not easy to manufacture long molybdenum rods. Generally, molybdenum rods of appropriate length are used as electrode rods. Therefore, since the molybdenum rod is connected, the lit pole rod is connected to another electrode rod using the threaded portion provided at the end of the lit electrode rod and used as an electrode rod. In the case of such electrode rods, sufficient contact cannot be obtained due to the contact accuracy and fitability of the threaded part, and the electrical contact resistance increases at the connection part, resulting in a temperature rise in this part. Problems such as breakage or breakage may occur at this part. This not only reduced work efficiency but also affected glass melting and caused defects in the quality of the glass.

Therefore, it has been desired to improve molybdenum electrode rods that do not cause such problems.

[Purpose of the invention]

The present invention has been developed in consideration of these points, and when molybdenum electrode rods used in glass melting furnaces are connected by fitting screws, it is possible to prevent defects caused by this connection part. The purpose of the present invention is to provide a molybdenum electrode structure and a method for manufacturing the same.

[Summary of the invention]

A long rod-shaped molybdenum electrode rod used by being inserted into a glass melting furnace is provided with a male thread on at least one end thereof, and a female thread is provided on at least the end surface of the other electrode rod. Connection is made by fitting the male thread of another electrode rod to be connected to the female thread of the electrode rod, and is characterized in that means for improving adhesion is applied to the joint surface of the electrode to be connected. For example, the bonding surface is tapered, and when connecting the electrodes, molybdenum paste is applied to the bonding surface of the end of the electrode rod, and then the electrodes are connected to form a molybdenum electrode structure. It is something to do.

In the molybdenum electrode structure connected in this way, the fit and adhesion of the connection parts are greatly improved, which greatly contributes to the prevention of electrode rod defects caused by the connection parts. done.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a side view of a molybdenum electrode rod having threaded portions at both ends. A male thread (3) is provided protruding from one end surface (2) of an electrode rod (1) made of molybdenum, and the electrode rod (1) is tapered to a connecting surface (4) for connection with another electrode rod. The diameter of the electrode rod is 50mm, and the diameter of the male thread is 2mm.
In order of 5, the taper angle (θ) is 45 degrees. On the other hand, the other end surface (5) is provided with a female thread (6), and the end surface (5) is provided with a female thread (6).
5) is a taper (forced) having a shape corresponding to the taper of the male thread.The diameter of the female thread is 25 mm, and the chimney angle (θ) is 45 degrees.

When the molybdenum electrodes formed in this way are connected to both end faces of the screw, the joint surface is tapered unlike the conventional flat surface, so the connection is very tight and there is no electrical contact when energized during use. It is possible to conduct a specified amount of current without increasing the contact resistance, and therefore there is no problem such as temperature rise in this part or breakage of the electrode rod in this part, and uniform glass melting can be performed. can be produced and high quality glass can be obtained.

Note that when molybdenum is melted by attaching an electrode rod to a glass melting furnace, the electrode rod wears out and the next electrode is connected, but at that time, the molybdenum is - Apply a paste (such as a paste made by dissolving molybdenum powder with water or a paste made by dissolving it in a solvent containing an organic binder), then fit and tighten the screws of the electrodes to be connected. Form an electrode structure.

In this way, the threaded parts fit well and the adhesion of the joint surfaces of the connected electrodes is greatly improved, resulting in good mechanical and electrical connections and extremely efficient glass melting work. can be done.

Note that the taper angle of the joint surface is ±2 around 45 degrees.
It is sufficient if it is about 0 degrees. Further, the molybdenum paste may be applied not only to the joint surfaces but also to the threaded portions for connection.

Furthermore, the shape of the joint surface is not limited to the one described above, but for example, as shown in FIG.
The side joint surface (7) is formed into a taper, and the externally threaded joint surface θ3) of the other electrode αυ fitted therewith is flat, and a washer a having a shape corresponding to the female thread side taper is formed.
A similar effect can be obtained even if a wire is inserted and connected. In addition, as shown in Figure 3, the shape of the end face of the electrode is the joint surface of one electrode Qυ provided with a male thread @ and the other electrode (2) provided with a female thread (24) connected thereto. It is also possible to form a step-like structure to improve the precision and reduce the contact resistance, thereby improving the adhesion.

〔Effect of the invention〕

When the molybdenum electrode rod of the present invention is installed in a glass melting furnace and energized, it does not cause an increase in electrical contact resistance at the connection part and does not cause problems such as breakage of the electrode rod, and can be used to melt glass very efficiently. Melting can be carried out.

[Brief explanation of drawings]

FIG. 1 is a side view of a molybdenum electrode rod of the present invention, and FIGS. 2 and 3 are explanatory diagrams of connecting portions of other embodiments of the present invention. 1...Molybdenum electrode rod, 3...Male thread, 6...
Female thread, 4, 7...Tapered joint surface, 14...Washer, 21.23...Molybdenum electrode. Agent Patent Attorney Mr. Inoue Figure 1 Figure 2 Figure 3

Claims (4)

[Claims] (1) A molybdenum electrode structure used in a glass melting kiln, characterized in that it is a molybdenum electrode having a male or female thread at one end, and a means for improving adhesion during electrode connection is provided on the joint surface of the electrode. (2) The molybdenum electrode structure according to claim 1, wherein the bonding surface has a tapered shape as a means for improving adhesion. (3) A male thread is provided at one end and a female thread is provided at the other end, and as a means of improving adhesion, the joint surface of the molybdenum electrode on the side where the male thread is provided is tapered, and the side where the female thread is provided. 2. The molybdenum electrode structure according to claim 1, wherein the joint surface is bored in the shape of a cheek corresponding to the male thread side taper. (4) When a molybdenum electrode used for glass melting is provided with a male or female thread at one end, the threaded part is fitted onto the threaded part of another electrode and tightened to connect the electrode. A method for manufacturing a molybdenum electrode structure, characterized in that a molybdenum electrode structure is connected by the presence of a molybdenum sheath.