OVENZZ Products Mixing and Using Information II I 3/30/16

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3 OVENZZ Products Mixing and Using Information II I 3/30/16 OVENZZ CAST Mixing and Using Information (Water calculated at lb/gallon) 55 lb bag 1000 lb bag 1500 lb bag Water Required Vibration Casting (Weight 12.7%) Pounds Gallons Liters Water Required Hand Casting/Pouring (Weight 13.5%) Pounds Gallons Liters For detailed mixing and using instructions, contact your HWI representative or visit Working Time Shelf Life (Under Proper Storage Conditions) minutes 365 days OVENZZ LW CAST Mixing and Using Information (Water calculated at lb/gallon) 55 lb bag 1000 lb bag 1500 lb bag Water Required Hand Casting/Pouring (Weight 25.0%) Pounds Gallons Liters For detailed mixing and using instructions, contact your HWI representative or visit Shelf Life (Under Proper Storage Conditions) days OVENZZ MORTAR Mixing and Using Information Material is supplied ready to use and can be field-adjusted as required. Water Required Thin Trowel Gallons Liters Water Required Dipping Gallons Liters Per 55 lb pail Note: As supplied, this is a thick trowel mortar; amounts of water (above) can be added if a thinner mortar is required, Always mix well when making such adjustments. Water Retention For detailed mixing and using instructions, contact your HWI representative or visit Shelf Life (Under Proper Storage Conditions) Minutes 180 days Page 1 of 1

4 OVENZZ Products (OV-1) II I Installation Guidelines 03/16/16 Safety and Health Review the Material Safety Data Sheet (MSDS) before using this product. The MSDS contains important information concerning potential health hazards and protective measures for these hazards. Contact your supervisor or safety director to obtain a copy. Storage Requirements For best performance, store the product in a dry location at temperatures between 60 F and 80 F. HWI packages its OVENZZ castables in poly-lined paper bags protected with plastic wrap to ensure dry product delivery. This packaging is not intended for outdoor storage. Always store OVENZZ castables on a dry flooring surface to prevent ground moisture from condensing into the package. Avoid storage in direct sunlight to prevent the packaging from deteriorating over time. Ensure that your inventory is rotated on a regular basis. OVENZZ castables have an average shelf life of 6 to 12 months and OVENZZ MORTAR has an average shelf life of 6 months. Refer to the product data sheet for specific shelf life recommendations. If product usability is questionable due to age, consult your HWI sales and technical representative. Compaction during shipping and storage can cause soft lumps to form in the material. This is not detrimental to product performance if the lumps can easily be broken by hand. If the OVENZZ castable material becomes damp during shipping and storage, a partial reaction of the binders can occur causing hard lumps to form. If the lumps cannot easily be broken by hand, do not use the product without first consulting your HWI sales and technical representative. Storage above 80 F can reduce the shelf life of OVENZZ MORTAR. Avoid storing OVENZZ MORTAR below 32 F. The product can be stored below this temperature for limited periods of time; however, care must be taken to bring the product temperature within range (60 F and 80 F) prior to installation. HWI packages its OVENZZ MORTAR in plastic pails protected with plastic wrap to ensure safe product delivery. This packaging is not intended for outdoor storage. Form and Backup Requirements Ensure that all casting forms are stout and watertight. Waterproof all porous forms, such as wood, and all porous backup linings before casting. Porous surfaces can reduce product properties and flow, resulting in a substandard installation. If installing over existing refractory, remove all loose material, debris, or contaminants prior to installation. Remove wood forms prior to dryout and heatup. Allowing wood forms to catch on fire can cause localized overheating and possible spalling of the refractory. Mixer Requirements OVENZZ castable products can be mixed in a drum, paddle, or other concrete type mixer. Small quantities can be mixed by hand with a hoe. The use of poorly maintained mixing equipment or inadequate mixing times can result in a mix that appears too dry, prompting the operator to add an excessive amount of water. Mixing time will vary from mixer to mixer; a mixing time of 4 to 7 minutes is typically suggested. OVENZZ MORTAR may require remixing before use. OVENZZ MORTAR can separate during storage. Never discard liquid that has pooled on top of the mortar. Mix this liquid back into the mortar before use. HWI recommends remixing OVENZZ MORTAR in the pail with a conventional high shear mixer mounted on an electric or air drill. Clean all mixing and handling equipment prior to use. Residual material in the mixer may affect the set of the product. Environmental Conditions For best results, ensure that the temperature of the product is between 60 F and 80 F prior to mixing. Temperature extremes affect working time, final set time, and final product quality. For hot weather installations, the mixing water may be cooled to extend working time. For cold weather installations, protect the installed product from freezing to prevent structural damage. Never install OVENZZ MORTAR containing ice crystals. This practice can result in voids in the joints and lead to joint failure. Page 1 of 3

5 OVENZZ Products (OV-1) Installation Guidelines Water Quality For best results, use drinkable water with a ph of 6 to 7.5 and a temperature of 60 F to 80 F. Water Addition Accurate water measurement is critical to achieve proper installation and optimum product properties. Refer to the product data sheet for water specifications. Water must be measured by weight or by volume. The water requirements for conventional castables vary. The information given on the product data sheet is a target value. Mix the first batch at the target value, then adjust the amount of water in subsequent batches based on the required flow for the installation. Varying the amount of water more than 2.5% above or below the target value shown on the product data sheet is not recommended without consulting your HWI sales and technical representative. HWI supplies OVENZZ MORTAR intended to be ready-to-use without adding water. It is acceptable to add small amounts of water to OVENZZ MORTAR in order to achieve a thinner consistency or to compensate for dryout and aging. Thoroughly mix the product after each addition of water. Do not add more water than necessary for the installation. Thinner mortar consistency results in lower mortar strength and increased shrinkage. Installation Methods OVENZZ castable products are designed for hand casting or vibration casting installation. For hand casting, rod the wet material to help remove trapped air. For vibration casting, either form vibration or immersion (pencil) vibration can be used. - For form vibration, ensure that you can control the frequency and time of the vibration. Vibration should be sufficient to densify the product without causing the material to segregate. Do not over-vibrate. - For pencil vibration, insert the vibrator to the bottom of the casting. Move and extract the vibrator slowly to avoid creating an air pocket. Install the product promptly after mixing. Mixer and batch sizes should be as large as possible to minimize the number of batches. Never continue to install subsequent batches if the first batches start to set. If this occurs, use a cold joint casting design between the current casting and the subsequent casting. Do not trowel or slick the surface of installed OVENZZ castables. This practice will prevent proper water removal during dryout. OVENZZ MORTAR is designed to be installed by thick patching, troweling or dipping. Mortar is always the weakest link in refractory brick installation. Mortar joints should be full and as thin as possible with no voids. Troweled mortar joints always offer improved performance over dipped mortar joints. If a delay occurs during installation, always cover the mortar with plastic to prevent dryout. Tightly reseal plastic pails to protect unused OVENZZ MORTAR. Curing For installations above 60 F, cure the product for a minimum of 24 hours. For installations above 60 F, cure the product for a minimum of 24 hours. For installations below 60 F, longer times are required to reach a hard set. Apply heat (not exceeding 120 F) to accelerate curing in cold conditions. Dryout and heatup can begin after the recommended minimum cure time as long as a hard set has been achieved. A hard set can be determined by striking the surface of the casting with a metal bar. A distinctive ring indicates a hard set. During curing, keep the surface covered and damp to avoid drying and cracking. Avoid direct water spray on the surface during curing. Avoid allowing the material to freeze prior to reaching a hard set or preferably prior to dryout (complete water removal). During curing, avoid applying excessive weight, such as equipment, to the cast surface. Alkali Hydrolysis in OVENZZ LW CAST: Alkali hydrolysis, also known as carbonation, is the formation of calcium carbonate caused by the reaction of lime in cement and carbon dioxide in the atmosphere. The hydrolysis reaction breaks down the cement bond, which creates a volume expansion that weakens the refractory lining surface. This weakened surface is friable and can peel off in ¼-in. to 1-in. layers depending on the severity. Page 2 of 3

6 OVENZZ Products (OV-1) Installation Guidelines High porosity and alkali content make lightweight castables susceptible to alkali hydrolysis, which can occur in unprotected linings exposed to weather conditions, especially rain. This reaction does not occur in protected linings, such as insulating linings that are protected by a solid structure on the back and a dense refractory on the front. Three steps must be followed to minimize/prevent the alkali hydrolysis reaction: 1. Cast and cure material at warmer temperatures to develop stable cement hydrates, which are more resistant to alkali hydrolysis (higher than 70 F is preferred). 2. Dry the material out as soon as possible after the 24-hour cure time. Drying will remove excess water and convert cement hydrates to more stable phases. The dryout temperature should be in the 500 F to 750 F range on the hot face to allow heat to penetrate the material and the temperature to reach at least 230 F part way into the lining. The lining does not have to be completely dried. Keep the material dry by covering it with plastic. Do not use surface sealants because they will break down over time and trap water inside the lining. The trapped water can act as a catalyst to promote the hydrolysis reaction. Dryout IMPORTANT: During dry out of a castable lining, only some water escapes via the hot face while most of the water is driven through to the cold face. If material is cast directly against a steel shell or other impermeable material without the use of weep holes, the water remaining in the lining will have no path to escape, and as the dry out schedule proceeds, internal steam pressure will rapidly increase resulting in probable lining damage and/or steam spalling. Dry out schedules issued by HWI assume that an unobstructed path exists through the cold face so that water can easily escape through the vessel/furnace shell. In most cases, weep holes are required to facilitate the removal of water/steam. Where weep holes are not allowed or a path to the weep holes is lengthy or not direct (such as a furnace hearth) some type of wicking should be used to create a path toward the weep holes or to the outside of the furnace. Dryout and heatup can begin any time after a hard set has been achieved. Refer to the curing and dryout schedule specified on the product data sheet for more detailed information on the appropriate curing, dryout, and heatup procedures. Tips When using metallic anchor systems, such as V-anchors, a coating on the tips is suggested to allow for anchor expansion during heatup. Wet down mixers and hoppers before beginning the mixing process. For OVENZZ LW CAST, add most of the water to the mixer before adding the dry castable. If your application requires weep holes, ensure that they are maintained before beginning installation. When using forms, apply a good mold release or grease before installation. Wash out all equipment as soon as installation is complete. A power washer is recommended. Always time the mixing process. Don t guess. For water, less is always best. Don t guess. Measure. Never use additives such as set extenders or accelerators without first consulting your HWI sales and technical representative. If a paddle or other mortar type mixer is used for re-mixing OVENZZ MORTAR, it is important to discharge the entire contents of the pail into the mixer. Improper mixing may affect product performance. Page 3 of 3

7 OVENZZ Products II I General Guidelines 03/16/16 Safety and Health Review the Material Safety Data Sheet (MSDS) before using this product. The MSDS contains important information concerning potential health hazards and protective measures for these hazards. Contact your supervisor or safety director to obtain a copy. Additional Guidelines HWI is not an oven product designer or assembler. HWI has no involvement in, and makes no warranties or representations about, the proper design or assembly of any finished products in which this component part shall be used. To the extent this component product is used in the assembly of an oven for food applications, the design of your oven may involve dangers associated with open flames and burning embers. You should consult with the designer and/or assembler of your oven for further information relating to its design or assembly and any risks that may arise as a result of the particular design or construction of your oven. Only components specifically rated and approved for use with food applications should be used in the assembly of food contact and food chamber sections of your oven. Do not use oven if bricks or mortar are cracked, chipped or broken. If bricks or mortar are cracked, chipped, or broken, immediately stop using your oven and contact a qualified contractor to perform repairs. Only components specifically rated and approved for use with food applications should be used in the repair of food contact and food chamber areas of your oven. Do not cut bricks. In the event that cutting of a brick is necessary a qualified contractor should be consulted. Children should not use oven. CAUTION: the design of your oven may involve dangers associated with open flames and burning embers. Exercise caution around open flames. Do not leave oven unattended while in use. Oven should be fully extinguished when use is completed. Consult with the assembler and/or designer of your oven to ensure that proper ventilation has been provided. Page 1 of 1

8 HWI Schedule 19 OVENZZ Heat up/dryout Schedule II I Curing and Dryout General Guidelines Field Use One Sided Dryout 3/29/16 Example: 9-Inch Lining Schedule Total Curing and Dryout Time 49 Hours 2500 Heatup from 1200 F to operating temperature at 100 F/hr 2000 Temperature F Ramp up at 100 F/hr Hold at 1200 F for 1 hr/in. of thickness 500 Cure time Minimum of 24 hrs at 72 F Cooldown from 1200 F to ambient at 100 F/hr 0 Hour Curing and Dryout Schedule (heated from the hot face) Cure Time Minimum ambient cure time (range of 70 F to 100 F) 24 Dryout Heat Sequence Heat from ambient to service temperature at 100 F/hr Total Dryout Time Total Curing and Dryout Time ~49 Hours ~25 ~25 Page 1 of 3

9 HWI Schedule 19 OVENZZ Heat up/dryout Schedule Curing and Dryout General Guidelines Field Use One Sided Dryout Notes For multi-layer lining designs, you must consider the total thickness of the various monolithics used in the lining as well as the specific dryout and heatup requirements of each product. Cure time is relative to ambient temperature. When installing below 60 F, you must either extend the cure time to fully hydrate the cement or add heat during the cure. Never begin dryout until a hard set is reached. Never let the temperature of uncured material drop below the freezing point. Ideally, the installed product should be kept above freezing until dryout is complete. The temperatures recommended in this schedule refer to the hot gases in contact with the refractory material and not the lining itself. Thermocouples must be placed about ½-in. away from the lining surface to ensure accurate temperature measurement during heatup. If castable material is installed without a permeable and unobstructed path to allow water removal from the lining through the cold face during dry out then weep holes and/or wicking must be used. Refer to HWI Dry Out/Installation Guidelines. If weep holes and/or wicking cannot be used, contact your HWI sales and technical representative for assistance. If dryout and cooldown are completed according to this schedule, subsequent heatup can be performed at 100 F per hr. All lightweight insulating castable products are susceptible it alkali hydrolysis. Detailed information on how to avoid this reaction is provided below. For linings thicker than 12 in., contact your HWI sales and technical representative. Alkali Hydrolysis in Lightweight Products Alkali hydrolysis, also known as carbonation, is the formation of calcium carbonate caused by the reaction of lime in cement and carbon dioxide in the atmosphere. The hydrolysis reaction breaks down the cement bond, which creates a volume expansion that weakens the refractory lining surface. This weakened surface is friable and can peel off in ¼-in. to 1-in. layers depending on the severity. High porosity and alkali content make lightweight castables susceptible to alkali hydrolysis, which can occur in unprotected linings exposed to weather conditions, especially rain. This reaction does not occur in protected linings, such as insulating linings that are protected by a solid structure on the back and a dense refractory on the front. Three steps must be followed to minimize/prevent the alkali hydrolysis reaction. 1. Cast and cure material at warmer temperatures to develop stable cement hydrates, which are more resistant to alkali hydrolysis (higher than 70 F is preferred). 2. Dry the material out as soon as possible after the 24-hr cure time. Drying will remove excess water and convert cement hydrates to more stable phases. The dryout temperature should be in the 500 F to 750 F range on the hot face to allow heat to penetrate the material and the temperature to reach at least 230 F part way into the lining. The lining does not have to be completely dried. 3. Keep the material dry by covering it with plastic. Do not use surface sealants because they will break down over time and trap water inside the lining. The trapped water can act as a catalyst to promote the hydrolysis reaction. CAUTIONS If high-pressure steam or excessive steam is observed at any time during heatup, the temperature must be held or reduced until steaming subsides. The schedule can then be resumed. Increasing the temperature during steaming can result in significant steam pressure buildup and possible steam spalling. Proper ventilation and air circulation within the furnace is required to remove steam and exhaust gases. Flame impingement on the refractory must be avoided. This will cause localized overheating and possible spalling. Remove wood forms prior to dryout and heatup. Allowing wood forms to catch on fire can cause localized overheating and possible spalling of the refractory. Many factors can impact safe dryout and heatup, including temperature uniformity, air exchange, and specific vessel designs. HWI cannot warrantee or guarantee the safe dryout and heatup of any specific vessel or refractory casting. However, following the general guidelines in this schedule has resulted in many successful installations. If you have specific questions or concerns, contact your HWI sales and technical representative. Page 2 of 3

10 HWI Schedule 19 OVENZZ Heat up/dryout Schedule Curing and Dryout General Guidelines Field Use One Sided Dryout Statements or suggestions concerning possible use of our products are made without representation or warranty that any such product is fit for such use or that such use is free of patent infringement of a third party. The suggested use assumes that all safety measures are taken by the user. Page 3 of 3

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