Skip to main content

Re: [MW:10408] OXY-ACETYLENE CUTTING

By Materials & Welding
Dear Friends
 
Basically the Cutabilty of any dpeneds upon following
i) In Oxy Ace Gas cutting Intially the point /region from where the metal is to be cut is being preheated to oxidation temp by Torch /nozzle outer periphery orifice  and later from central orifice oxygen is blown by which further oxidation of metal takes place and  later on the molten slag is blown out by oxygen pressure / flow
from  the creft formed in the plate
ii)Now in case of CS plate cutting , During the process of oxidation of Cs  by intial preheating and subsequent blowing of oxygen through central orifice ,There is a exothermic reaction and heat is generated and this heat melts the oxide of Iron. and molten slag of this Iron oxide being forcly removed by oxygen jet produce through central orifice of the Nozzle. and this way the cutting action takes place .
iii) In case CS (Iron) the oxide of iron formed during preheating  and also oxygen blowing have its melting temp. less than the melting temp of Iron Therefore CS is having good cutabilty and we can cut CS plate smothly by Oxy Acetyl gas
iv) While as in case of SS or Aluminium the oxide form during cutting operation having its melting point is more than its parent metal Therefore its cutabilty is very poor and you can not cut SS ,Al /NF by oxy-Acetyln gas ,In such case you require to cut these material by Plasma cutting(In case of SS cutting Chromium oxide forms and its melting point is much higher than parent metal similarly for Aluminum Al2O3 is formed)
 
Warm Regards
 
Hegde P.B.

From: ELDHO ISAAC <eldho.isaac@rediffmail.com>
To: "materials-welding@googlegroups.com" <materials-welding@googlegroups.com>
Sent: Thu, 17 March, 2011 2:21:04 PM
Subject: [MW:10400] OXY-ACETYLENE CUTTING

Dear All,

Is it possible to use oxy-acetylene flame cutting method, for cutting of Aluminium and Stainless steel.??
Please give suitable reasons and references for your valued answers.

Thanking You,

Regards,

Eldho Isaac.

--
To post to this group, send email to materials-welding@googlegroups.com
To unsubscribe from this group, send email to materials-welding+unsubscribe@googlegroups.com
For more options, visit this group's bolg at http://materials-welding.blogspot.com/
The views expressed/exchnaged in this group are members personel views and meant for educational purposes only, Users must take their own decisions w.r.t. applicable code/standard/contract documents.

Comments

Post a Comment

Popular posts from this blog

Re: [MW:34105] SA266 GR4N 4 Cycle SPWHT

By Materials & Welding
Hi,  You are correct, Minimum refers to the one cycle for which this part will expose until final work shop PWHT. hence mill test certificate shall include this.  Max. SPWHT, refers to additional cycles of heat treatment that are reserved for future repairs during equipment lifetime.  Again, these simulated no. Of cycles shall be specified in MTC.  The idea is we need to make sure that steel mechanical properties are not compromised upon exposure to multiple repairs (i e 4 cycles in your case).  One could say, if steel is subjected to 4 cycles and is ok, then it should by defacto be good for one cycle, yet, this is wrong assumption cause mechanical problems and microstructure of materials varies accordingly based on no. Of cycles for which material will expose. This is apparent in alloy steel and especially for impact test values as an example.  In your case, this forged CS with properties before PWHT can be understood to be " as forged" condition (i.e. Wit...
Post a Comment
Read more

Materails FAQs

By Materials & Welding
Q: What are equivalents for standard Q 235 B (and Q 235 A) for U-channels? (asked by: boris.vielhaber@vait.com) A: DIN Nr. = 2393 T.2, 2394 T.2, EN 10025 W. Nr. DIN 17007 = 1.0038 Design DIN 17006 = RSt 37-2, S235JRG2 (Fe 360 B) Q: What is St DIN 2391 BK material? (asked by: dmcandrews@automaticstamp.com) A: Precision steel tubes, cold-finished/hard. Q: What is C.D.W. Boiler Tube? (asked by: montydude123@yahoo.com) A: Cold Drawn Welded Boiler Tube. Q: WHAT IS W.Nr. 1.4301? PLS TELL US IN EASY LANGUAGUE (asked...
21 comments
Read more

Heat tint (temper) colours on stainless steel surfaces heated in air // Heat tint

By Materials & Welding
Introduction The colour formed when stainless steel is heated, either in a furnace application or in the heat affected zone of welds, is dependent on several factors that are related to the oxidation resistance of the steel. The heat tint or temper colour formed is caused by the progressive thickening of the surface oxide layer and so, as temperature is increased, the colours change.   Oxidation resistance of stainless steels However, there are several factors that affect the degree of colour change and so there is no a single table of colour and temperature that represents all cases. The colours formed can only be used as an indication of the temperature to which the steel has been heated. Factors affecting the heat tint colours formed Steel composition The chromium content is the most important single factor affecting oxidation resistance. The higher the chromium, the more heat resistant the steel and so the development of the heat tint colou...
Post a Comment
Read more