SU67392A1 - Method of electric arc surfacing of cast iron products - Google Patents

Description

Electric arc welding of cast iron (products, in particular, during restoration of evacuated parts, is connected in practice 1 with the difficulty that the hardness of the weld seam is quite significant: (45-55 units on the Rockwell C scale) and the mechanical treatment of the deposited spot requires the use of abrasive materials, that with low availability (a weld is impossible in a number of cases. Increased hardness is explained by the fact that under normal conditions of weld surfacing the temperature develops above the critical and metal is hardened.

In (The practice of electric arc welding of thin-sheet steel. It is known to use copper pads to remove heat from the edges of the sheets being welded and thereby prevent overburdening of the latter.

According to the present invention, it is proposed to use a similar method for electric arc ironing of cast iron products in places forming thin walls, protrusions, etc. (ianrnmer, when restoring the teeth of the pile machine disks), in order to impart a reduced hardness to the weld metal, which allows (subsequent machining of the site of surfacing without assistance. and abrasives.

To accomplish this, a massive copper piece is placed in the immediate 6jTH30CTH from the deposition site and the necessary configuration is: forming the mold for the weld metal and ensuring energetic heat removal from it.

The foregoing is illustrated in the drawing, which shows a part of a platter of a pile machine with several teeth, of which / are normal teeth, 2 are worn. For their restoration, a shaped copper piece 5 is inserted into the groove between the teeth, having a conf-uration corresponding to the shape of the weld metal 4. In the presence of the detail 5, the weld hardness is minimal and Rockwell equal (scale C) on the surface 15-18 units and in the middle of the seam - 19-23 units.

The reason for this is the good thermal conductivity of copper, so that at the time of fusing heat is vigorously removed, the temperature of the seam decreases at the critical (quenching) and consequently subqualification is eliminated, which takes place under normal conditions of surfacing.

The resultant welding of the grooves on the proposed spm is fully amenable to machining with any tool (chisel, file, chisel, cutter, drill, etc.), as shown in the drawing, where 5 denotes a tooth obtained by machining the weld metal 4.

Thanks to the seam processing

is facilitated by AND-cheapening, - and besides Togsu CTaHOBil.TCii, affordable, in particular, I. and ::;. p; p; starratsni details, In; Those 1: Hulu and-x |:, Kog, and abrasive material cannot be impregnated (because of the inaccessibility of place)

Thus, this invention essentially extends the scope

use of electric arc

surfacing.

The subject is both acquired and

Method, electric arc surfacing of cast iron products in places that form thin walls, protrusions, etc. 1P. (for example, when restoring the teeth of the disks of the pile machine), characterized in that, with the cut of the deposited metal of the initial hardness, which enables subsequent machining of the weld site without the help of abrasives, a massive copper part of the desired KONfugrone body is placed in the direct proximity of the weld position to the HF pattern. forming the form for the deposited metal and ensuring the strong removal of heat from it.