Print This Post
Thank you for choosing our products.
The following instructions will help you make the most out of our quality.
MAT 50 S
- Short Description: Monolithic, hydraulic-bonded, Dense Castable material with normal cement content. These instructions do not cover the medium cement castables as well as the L.C.C. (Low Cement Castables) and the U.L.C.C. (Ultra Low Cement castables).
- These refractory materials are packed in special paper sacks, of about 25 Kgr, in wooden pallets.
- Shrink foil wrapping protects the refractory materials against moisture.
- These refractory materials should be stored in dry place and cool warehouse (shelf life is indicative to the Technical Data Sheets).
- Pallet stacking is admissible and the max loaded pallets must not exceed 3 pallets. If the shelf life has been exceeded, our Technical Service Department should be contacted before use.
- “First in – First out” management of stored materials is advisable.
- The material has to be stored above freezing temperature.
- Due to high humidity and strong solar radiation in tropical countries, storage in a dry, covered place is recommended.
- The shrink wrapping should be removed only prior to mixing.
- Tools and Machnery/ Preparation before casting
- Tools, mixer, vibrators and surrounds must be clean and free from foreign material.
- The mould has to be stable to withstand stresses caused by vibration and the weight of the castable. The mould must be water tight. Always apply release oil to prevent the mould from adhering to the refractory material.
- In a compulsory/ forced action/ paddle mixer, or during mixing by hand, lumps can be produced which are dry inside and will not allow homogeneous curing.
- This castable material has to be installed by vibration. Internal or external vibrators can be used. An external vibrator can vibrate the whole mould. Therefore, the filling of the mould has to be completed before curing, as vibration could disturb the curing process.
- Dimensions and energy output of internal vibrators have to correlate with the wall thickness.
- The area for casting must be clean.
- The shuttering of the moulds (wood forms) as well as the back up materials should be waterproofed in order to minimize the water absorption from the mixed refractories. The shuttering can be removed after 24 hours by which time the exothermic reaction of alumina containing castables has taken place. The temperature increase should be checked with a recorder.
- Water required (lit/100 kg) (EN 1402-4): 9.8-11.5
- Material Required at kg/m3 : 2250
- Dense castables are designed to be applied by casting.
- The intensive mixer and the accessories must be clean.
- Do not mix refractory materials less than full paper bag.
- The optimum quantity of dry material depends on the mixer capacity.
- Only potable, drinking water must be added for the mixing of these refractory materials.
- Mix the dry material for about 30 sec to homogenize it and then add the min amount of water. Wait for 2 minutes in order to have a sufficient mixing and then, if necessary, add slowly the remaining water up to the maximum water demand until the required consistency has been reached.
- Continue the mixing for 2 minutes more. Do not exceed the prescribe water content for each type of the refractory materials under any circumstances.
- Minor adjustments to the added amount of water are permissible in order to achieve the desired flowability. Do not exceed the prescribed water content for each type of the refractory materials under any circumstances.
- The added water as well as the refractory materials must be at temperatures higher than 10°C.
- For application under 10oC the addition of accelerator is recommended. Otherwise a prolonged setting time is observed.
- The mixed castables (based on cement) must be installed within 20 minutes.
- To avoid separation lines it is necessary to cast “wet in wet” and finish a complete section at a time.
- Immersion vibrators can homogenize the interface layers. To avoid holes these vibrators have to be pulled out very slowly.
- If no air bubbles can be seen on the surface, the vibrator can be turned off until the next batch is ready.
- Do not trowel to slick a finish surface.
- Keep the surfaces damp and/or covered for at least 24 hours.
- The refractory materials must be set prior the starting of dry out.
- The setting time is strongly affected by the temperature.
- Protect the cast materials from freezing because freezing of these materials prior to water removal can cause structural damage.
- Anchoring & Supporting
- Depending on the dimensions and the location of the refractory lining it is necessary to use anchors; for temperatures up to 1200°C, steel anchors can be used and over 1200°C, ceramic anchors must be used.
- Refractory grade anchors can be selected depending on the highest temperature, the corrosion environment and the specific project conditions.
- Steel anchors can be selected depending on the highest temperature. They must be painted with bitumen or insulated with tape to avoid cracking.
- Steel anchors have to be protected with 30 mm of refractory material against the hot face.
- Drying and Heating up
- Cement based castables must be dried before starting pre-heat.
- All castables have to be compatible with the pre-heat schedule for the whole kiln.
- The drying and pre-heat temperature is available on request from our Technical Service Department.
- Winter precautions
- If the temperature at the point of installation is below 5°C, pre-heating is strongly recommended.
- Temperature during setting should be the freezing point.
- In case of, out of temperature limit conditions, please contact our Technical Service Department.
Important Note: The above instructions are suitable for the most of uses. The final User must follow carefully the instructions of Designer of each specific project.
Print This Post