Livarski vestnik 59/2012 Nr. 3

Jonas Oldin
Calderys Nordic AB, Göteborg, Sweden
QD: QUICK DRYING-A NEW GENERATION OF CASTABLE: THE ADVANTAGE OD QD CASTABLE IN FOUNDRY LADLE

Jožef Medved1, Silvia Gaiani2,3, Maja Vončina1, Primož Mrvar1, Robert Tisu2
HIGH TEMPERATURE OXIDATION OF Ti MATERIALS

Kosour V., Vascak T., Horacek M.
WAX INJECTION SIMULATION

A.Brili, J.Kemperle, B.Taljat
SHOT SLEEVE AND PISTON ASSEMBLY FOR HIGHEST EFFICIENCY IN HPDC


Jonas Oldin
Calderys Nordic AB, Göteborg, Sweden

QD: QUICK DRYING-A NEW GENERATION OF CASTABLE: THE ADVANTAGE OD QD CASTABLE IN FOUNDRY LADLE
Introduction

 

In many foundry operations, transport, pouring and treatment ladles are commonly lined with conventional castable, LCC, ULCC or wet ramming/plastic refractory. This can bring several disadvantages, such as reduced life and cracking due to thermal cycling. Refractory linings in foundry ladles are constantly exposed to thermal cycling. This high load of thermomechanical stress leads to cracks. The constant thermal cycling of the refractory lining is one of the essential factors that determine the life of the lining. The structure of production lines gives an unfavourable temperature fluctuation in the transport and pouring ladles. These problems are created due to preheating availability, cold tapping and production tempo. The ladle handling is subordinate to the demands of production.

Furthermore there is always a demand to save energy and the long drying cycles with today’s lining this is a clearly improvement field.

Availability of ladles is also very essential in today’s foundry operation. The turn around time from scraped to new ladle lining with conventional castable, LCC, ULCC is very time consuming, the installation steps and curing and drying of the castable prior to operation locks the ladle from production. An improvement in a shorter turn around time gives a more flexible ladle park and less manhours in the refractory shop.

Furthermore, a strictly controlled long drying programme is always required for conventional castable, LCC, ULCC or wet ramming/plastic refractory. The safety aspects need to be considered at every stage of the operation. Drying of these lining is an energy and cost intensive operation.

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Jožef Medved1, Silvia Gaiani2,3, Maja Vončina1, Primož Mrvar1, Robert Tisu2

HIGH TEMPERATURE OXIDATION OF Ti MATERIALS


Abstract

The high temperature oxidation behaviour of various Ti alloys was studied at 800 °C and 900 °C in air atmosphere. Oxidation tests were performed at isothermal conditions. As reference material Ti-Gr.2, which showed the lowest high temperature oxidation resistance, was used. Alloys Ti-Gr.37 A and Ti-Gr.37 B have better oxidation resistance whereas the alloy with higher Al content shows a little higher susceptibility toward the oxidation. A trademark alloy Ti-exhaust, developed for exhaust application, shows the best high temperature oxidation resistance.

Keywords: Ti alloys, high temperature oxidation, thermogravimetry

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Kosour V., Vascak T., Horacek M.


WAX INJECTION SIMULATION

Brno University of Technology, Faculty of Mechanical Engineering, Institute of Manufacturing Technology, Technicka 2896/2 Brno, Czech Republic, http://www.fme.vutbr.cz/, tel: +420 541141357, email: ykosou00@stud.fme.vutbr.cz

Keywords: Investment Casting, ProCast, Simulation, Wax Injection, Wax Pattern

Abstract

The article deals with the preparation and optimization of numerical simulation of wax injection in the ProCast software. The article describes optimization and validation of the wax flow simulation when making wax patterns. A simple injection die has been designed for the validation of the “prototype” simulation. Its filling on injection machine is being recorded on digital video recorder and the obtained data from these experiments compared to computer predication. Optimized “prototype” simulation has been then used for more complicated shapes of real wax patterns.

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A. Brili, J. Kemperle, B. Taljat


SHOT SLEEVE AND PISTON ASSEMBLY FOR HIGHEST EFFICIENCY IN HPDC

Abstract

 

Shot sleeve used in high-pressure die casting industry is studied to enhance its performance and in-service life.  Based on in-situ testing and computational modelling of sleeve operation, improvements of sleeve design, material selection, and surface treatment are made.  Two different shot sleeve designs are proposed for particular in-service conditions.  Most important advantages are improved temperature homogeneity in the sleeve section, reduction of overheating in pour region, and as a consequence significant reduction of sleeve axial bending and ovalization of the bore hole.  These results present substantial improvement in both sleeve and piston in-service performance.  A new generation of casting pistons is developed.  The sleeve-piston assembly is studied to achieve optimum in-service life and performance.

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