Search for dissertations about: "rolling defect"

Showing result 1 - 5 of 15 swedish dissertations containing the words rolling defect.

  2. 1. Evolution of artificial defects during shape rolling

    Author : Mirjana Filipovic; Stefan Jonsson; Per-Olov Perä; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; shape rolling; wire rod rolling; artificial defects; defect evolution; surface cracks; porosity; FEM; high speed steel; stainless steel; Other materials science; Övrig teknisk materialvetenskap; Initiering och utveckling av defekter under spårvalsning;

    Abstract : Very often defects are present in rolled products. For wire rods, defects are very deleterious since the wire rods are generally used directly in various applications. For this reason, the market nowadays requires wire rods to be completely defect-free. Any wire with defects must be rejected as scrap which is very costly for the production mill. READ MORE

  4. 2. Influence of surface roughness on rolling contact fatigue considering thermal elastohydrodynamic lubrication effects : Due to Corona it is not possible to attend this defense in person, instead attend via this link: https://play.kth.se/media/0_omfsppe6

    Author : Carl-Magnus Everitt; Bo Alfredsson; Andreas Almqvist; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Contact mechanics; Rolling contact fatigue; Pitting; Spalling; Slip; Thermal elastohydrodynamic.; Kontaktmekanik; Rullande kontaktutmattning; Pitting; Glidning; Termisk elastohydrodynamik.; Hållfasthetslära; Solid Mechanics;

    Abstract : Rolling contacts are utilized in many technical applications, both in bearings and in the contacts between gear teeth. These components are subjected to high loads in many of their applications. The high loads causes very high contact pressures which may cause rolling contact fatigue, often denoted as pitting or spalling. READ MORE

  5. 3. Surface and Inner Deformation during Shape Rolling of High Speed Steels

    Author : Kristina Nordén; Stefan Jonsson; Jan-Olov Perä; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Metallurgical manufacturing engineering; Metallurgisk produktionsteknik;

    Abstract : Shape rolling is a common manufacturing process used to produce long products i.e. bars and wire. One of the problems that might occur during rolling is defect formation leading to rejection of the finished product. READ MORE

  6. 4. Roll pass design for improved flexibility and quality in wire rod rolling

    Author : Conny Eriksson; Ulf Ståhlberg; Magnus Jarl; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Materials science; wire rod; roll pass design; working range; productivity; swedish wire rod mills; Materialvetenskap; Materials science; Teknisk materialvetenskap;

    Abstract : The thesis treats roll pass design in wire rod rolling of stainless steel for sequences and series built up by two-symmetrical grooves. It is focused on predicting rolling flexibility, also called working range, as well as product quality. For analysing the flexibility a computer program has been developed. READ MORE

  7. 5. Condition-Based Maintenance: Selection and Improvement of a Cost-Effective Vibration-Based Maintenance Policy for Rolling element Bearings

    Author : Basim Al-Najjar; Sherwin David; Bo Bergman; Produktionsekonomi; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; vibration and acoustic engineering; vacuum technology; hydraulics; Mechanical engineering; a cost-effective vibration-based maintenance policy.; Integrated maintenance; Condition monitoring and control; Total Time on Test-plots; Vibration monitoring; effectiveness and accuracy; Failure causes and mechanisms; Maintenance quality; Maskinteknik; hydraulik; vakuumteknik; vibrationer; akustik; Commercial and industrial economics; Industriell ekonomi; Maintenance Technology; Terotechnology;

    Abstract : Modern machinery is expensive and therefore must run at high availability and effectiveness which cannot be achieved without an effective maintenance policy. Condition monitoring, (CM), techniques can be utilised to reduce or arrest the rate of deterioration of a component so increasing operating life. READ MORE