JPH0191972A - Torch for plasma cutting - Google Patents

Abstract

PURPOSE:To extend the service life of a nozzle by forming an electrode of Cu and burying a burying member such as Hf in its tip central part and also, forming the nozzle of Cu and burying a burying member such as Hf in its tip central part to reduce consumptions of the electrode and a plasma nozzle. CONSTITUTION:The electrode 1 for generating an arc is formed of the Cu or a Cu alloy as base material aud fixed by an electrode supporting body 4 by piercing space for a gas path 3 on the nozzle 2 of a torch. The first burying member 5 made of the Hf, etc., or composite material thereof is buried in the tip central part of the electrode 1. The nozzle 2 is also formed of the Cu or the Cu alloy as base material and the second burying member 6 made of the Hf, etc., or the composite material thereof is buries in its tip central part and the plasma gas nozzle 7 is formed on said burying member 6. By this method, the consumption of not only the electrode but also the plasma nozzle is reduced and the service life of the nozzle can be extended.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a plasma cutting torch used primarily for cutting metal.

BACKGROUND OF THE INVENTION In a conventional plasma cutting torch that uses an oxidizing gas (02, air, etc.) as a plasma gas, the electrode 11 is made of copper or a copper alloy in order to prevent the electrode 11 from being worn out, as shown in FIG. , a method is often used in which a buried member 12 made of hafnium or zirconium is embedded in the center of the tip and the copper or copper alloy part is strongly cooled with water or gas. The conventional method used was to make it up to 6 times with water or gas.

Problems to be Solved by the Invention In the conventional plasma cutting torch, the nozzle 13
However, since it is composed only of copper or a copper alloy whose oxide has a not very high heat resistance temperature, there is a problem in that the plasma gas ejection hole 14 at the tip of the nozzle 13 is severely worn out.

The present invention solves the above-mentioned problems, and aims to provide a plasma cutting torch with excellent durability of the plasma gas ejection hole at the tip of the nozzle.

Means for Solving the Problems In order to solve the above problems, the torch of the present invention has an electrode made of copper or a copper alloy, and hafnium, zirconium, rhenium, yttrium, or a composite thereof at the center of the tip. In addition to embedding the first buried member made of material, the nozzle is also made of copper or copper alloy,
A second embedded member made of hafnium, zirconium, rhenium, yttrium, or a composite thereof is drilled into the center of the tip, and a plasma gas ejection hole is formed in this second embedded member. .

Hafnium, zirconium, rhenium, yttrium, and their composites have high heat and humidity resistance due to their oxides, so even when the nozzle is used in an oxidizing gas atmosphere, the tip of the electrode and the plasma gas nozzle are Less wear and tear.

Example Embodiments of the present invention will be described below based on the drawings.

FIG. 1 is a sectional view of the tip of a plasma cutting torch showing an embodiment of the present invention. In Fig. 1, reference numeral 1 denotes an arc generating electrode made of copper or copper alloy as a base material, which is fixed to the nozzle 2 of a plasma cutting torch with an electrode support 4 with a gas passage 3 spaced therebetween. A first embedded member 5 made of hafnium, zirconium, rhenium, yttrium, or a composite thereof is embedded in the center of the tip. Further, the nozzle 2 is also made of copper or a copper alloy as a base material, and a second buried part 6 made of hafnium, zirconium, rhenium, yttrium, or a composite material thereof is embedded in the center of the tip. A plasma gas ejection hole 7 is formed at 6 .

In the above configuration, the first embedded member 5 is embedded in the center of the tip of the electrode 1, and the second embedded member 6 is embedded in the center of the tip of the nozzle 2 and has the plasma gas ejection hole 7 formed therein. , are made of hafnium, zirconium, rhenium, yttrium, or a composite material thereof, whose oxides have a high heat resistance temperature, so even when these are used in an oxidizing gas atmosphere, their consumption is small.

FIG. 2 shows the shape of the plasma gas nozzle 8 formed in the second buried member 6 gradually increasing in size as it approaches the nozzle outlet side. The plasma gas that is narrowed down by the sections is ejected at high speed, and it also has the effect of being a die percent nozzle with a high cutting speed.

In addition to the effect of the north gate, according to the present invention, hafnium, zirconium, rhenium, etc. whose oxides have a high heat resistance temperature are used not only at the center of the tip of the 71i fi but also at the center of the tip of the nozzle where the plasma gas ejection hole is formed. Since a buried member made of a type of yttrium or a composite material thereof is embedded, not only the electrode but also the plasma nozzle is consumed less, thereby extending the life of the nozzle.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of the tip of a plasma cutting torch showing an embodiment of the present invention, FIG. 2 is a cross-sectional view of the tip of a plasma cutting torch showing an embodiment of the present invention, and FIG. 3 is a conventional FIG. 3 is a cross-sectional view of the tip of the plasma cutting torch of FIG. DESCRIPTION OF SYMBOLS 1... Electrode, 2... Nozzle, 5... First buried member, 6... Second buried member, 7, 8... Plasma gas ejection hole. Agent Yoshihiro Morimoto Figure 1 Figure 2 Figure e

Claims (1)

[Claims] 1. The electrode is made of copper or a copper alloy, and a first embedded member made of one of hafnium, zirconium, rhenium, yttrium, or a composite material thereof is embedded in the center of the tip, and the nozzle is also made of copper or copper alloy. Plasma cutting in which a second embedded member made of a copper alloy, one of hafnium, zirconium, rhenium, yttrium, or a composite thereof is embedded in the center of the tip, and a plasma gas ejection hole is formed in this second embedded member. torch. 2. The plasma cutting torch according to claim 1, wherein the diameter of the plasma gas nozzle is gradually increased as it approaches the outlet.