This newsletter highlights three important points – this time about tundish dry mixes, which we have been developing for a long time.
1. User-friendly
Tundish dry mix is a commonly used wear lining practice where the dry mix is set between the tundish form and the back lining material. The wear lining is normally hardened by using either heat from the back lining or form heating.
We have developed probably the fastest dry mix installation machine on the market, which can feed dry mix simultaneously from each wall to the pool in just about 30 seconds. Learn more about our Cruiver installation equipment here.
A typical challenge with using dry mix is the dust that generates in the tundish area during installation and when breaking the bags for the installation equipment. The problem can be solved by delivering the material in bulk form by silo truck to the customer’s silo, from where a screw conveyor feeds it to the installation equipment. This practice also eliminates the generation of pallet and bag waste and reduces internal logistics as there is no need to move the bags with a crane.
We also work to minimise dusting by modifying the composition of the mix. We customise all our dry mix products by evaluating the appropriate particle size distribution and dust binding agent amount for each customer. This makes the application of the dry mix as easy as possible.
2. Steel quality
The raw materials chosen for the mix affect the steel grade. That is why we always consider our customers’ most critical steel impurities and adapt our products accordingly.
Binders can cause sulphur, phosphorus, hydrogen or carbon pick-up. For this reason, we use a range of binder options to create a mix that does not critically contaminate the customer’s steel.
The choice of aggregates is also important. Magnesium oxide, olivine or a mixture of these are typical aggregates. In making the selection, we take into account, among other things, the temperatures during casting and the thermal conductivity of the lining. Aggregate choices also affect the cost of the lining.
3. Functionality
By functionality, we mean the practical functionality of the material in the process: its ease of installation and functionality in the preheating and casting process, as well as the release of the lining in the desculling process after use.
The material must have sufficient strengths for the process temperatures so that the lining remains undamaged during the preheating and casting process.
The particle size distribution plays an extremely important role in the functioning of the mix – this has been clearly demonstrated by both our research and practical tests. In the installation phase, we always choose the option that guarantees a sufficiently good flow of the mix from the installation equipment to the space between the form and the back lining. With the right choice of binder, we prevent the mix from sticking onto the form. Choosing the particle size distribution correctly can minimise steel penetration into the lining while maintaining a sufficient amount of appropriately sized pores. The correct particle size distribution minimises the risk of wear lining sintering to the back lining. It also allows easy removal after use, which keeps the back lining in good condition for longer and reduces wear lining consumption.
If you want to improve your tundish process, please contact us!
