Daniela MILOŞTEAN


32-38 STAREA DE TENSIUNI ȘI DEFORMAȚII LA PERFORAREA ȚAGLELOR PENTRU ȚEVI FĂRĂ SUDURĂ

TENSION AND DEFORMATION state at billet perforation for seamless pipes

 

The paper analyses the particularities of perforation through helical rolling of filled billets to achieve blanks for seamless pipes. Also, clarify the plastic flow phenomenon caused by the stress and strain state, which determine the formation of the cavity.

 

Keywords: rolling helical cylinder bitronconic cavity, blanks, seamless, tubes (laminate tubes)

Cuvinte cheie: laminare elicoidală, cilindri bitronconici, cavitate, eboșe, țevi fără sudură (țevi laminate)

Descarcare text


32-36 FINISAREA EBOȘELOR PENTRU ȚEVI DESTINATE INDUSTRIEI PETROLIERE

finising blanks for pipes intended to oil industry

 

The paper analyses the Mannesmann process of blanks rolling into pipes of a certain wall thickness and diameter. Also, is focuses on pipes finishing in the size range of 400-900 mm for the exterior diameter, used for gas and petroleum products transportation.

 

Keywords: rough pipes, rolled widening, rolling on the cork, mill Smoothing, rolled pipes

Cuvinte cheie: eboșe pentru țevi, laminare de lărgire, laminare pe dop, laminor netezitor, laminare țevi

Descarcare text


30-13 OPTIMIZAREA ÎNCĂLZIRII UNOR OŢELURI DE CALITATE ÎN VEDEREA PRELUCRĂRII PLASTICE

HEATING OPTIMIZATION OF HIGH GRADE STEELS
FOR PLASTIC PROCESSING
The research aimed at finding solutions for the dissolution in the
structural matrix of steel and the improvement in deformability. The results
allowed the optimization of the technology by reducing the heating-up duration,
and by dissoluting and globulising the ferrite.
Keywords: plastic processing, steel, structure
Cuvinte cheie: prelucrare plastică, oţel, structură

Descărcare text 


26-68 CURĂŢIREA SUPRAFEŢELOR METALICE PENTRU TRATAMENTE IN-SITU

CLEANING THE METALLIC SURFACES FOR IN-SITU TREATMENTS
The paper presents a study on the native oxide film formed on steels surface by air exposure at ambient conditions and its cleaning. As in-situ thermochemical treatments require a clean and active surface, argon ion sputtering process is usually employed to eliminate this superficial oxide layer.
Keywords: atmospheric oxidation, steel, iron oxides, ionic bombardment

Descărcare text