Installation Procedures


HAND PACK INSTALLATION

The mixing of ACTCHEM® is critical to its performance and particular attention should be paid to the following procedures: (PAN MIXERS NOT RECOMMENDED)

1.0 EQUIPMENT - Planetary mixer (Hobart Type)

1.1 Only mixers in good, clean, working order are permitted for use.

1.2 Bowls and paddles must show no wear and be clean.

1.3 Mixer capacity should be the correct size to mix a fixed batch weight: 60 liters capacity for 20 kgs. batch.

1.4 Mixer should operate at low speed setting

1.5 Mixing time is 5 min. Do not mix to sound or eye.

1.6 Additional water can be added AFTER the 5 min. mixing time has expired. Add additional
at a rate of 0.25% and mix for 1 min. Continue this procedure until proper consistence is
found. Changes in ambient conditions may required water percentage changes. Water changes has no adverse effects on physical properties.

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2.0 EQUIPMENT - Paddle mixer (for Refractory Concrete)

2.1 It is recommended that gas or diesel powered paddle mixers designed for heavy Refractory Concrete be utilized to mix ACTCHEM. With these mixers a governor should be used to increase the RPM of the drive to 35 - 45 RPM's.

2.1 The rubber blades must show no wear, be clean and be within 1 mm of barrel.

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3.0 OTHER EQUIPMENT:

3.1 Proper dust masks and eye protection should be used by all mixing and installing personnel.

3.2 An accurate water-measuring device is required, with precise gradations clearly shown.

3.3.1 Trowels, for cutting and leveling. No special surface preparation is allowed.

3.4 Clocks to measure mixing times, one per mixer.

3.5 Rubber gloves are required for installing the product.

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4.0 MIXING PROCEDURE:

4.1 a. Two component (Actchem® ESL)
Combine aggregate and powder into the mixing chamber. Mix for two minuets prior to adding water. Cover mixing chamber with plastic to reduce loss of fines. Add appropriate water and mix per para. 4.3.

b. Single component (Actchem®)
Place entire container of material into mixing chamber. Mix per para 4.3

4.2 Water Content is important to achieve the best installation material consistency. Use the same water content as shown on the PRE QUALIFICATION data sheets, for the first mix. Use 4.5% if no data sheets are available. Thereafter, water contents should be adjusted to suit the local conditions, i.e., humidity, ambient temperature, steel fibers etc. Adjustments in water contents should be in gradations of no more than 0.1% each time, with additional mixing times of at least two minutes. Over mixing should be avoided as this creates too much friction heat in the mix, which can cause premature setting times.

4.3 Mixing times are critical. The minimum mixing time is five (5) minutes. With a paddle mixer, mixing times as high as 10 minutes may be required. It is advised to mix at a low speed setting initially, to reduce fine powder losses, and then switch the mixer to medium speed on a Hobart Mixer and 40 - 45 RPM's on a paddle mixer. In a Hobart Type mixer, the mix will firstly look dry, at 1.5 - 2.0 minutes a distinct change will occur, the mix will start to mix together. At 3.5 minutes the mix will still look to dry and have a gravel like appearance. At 3.5 to 5 minutes, the material will knit together to form distinct big lumps with smooth tops, and a dense putty consistency. After 5 minutes, stop the mixer and feel the workability by hand; if it sticks to your hand, too much water was added, adjust as required for future batches. For paddle type mixers, double the minuets above. Never add more water until the mixing times have expired.

4.4 Water temperatures shall ambient. Use only clean potable water with a PH between 6 and 8. The abrasion loss values of ACTCHEM are not dependent on water temperature or water volume. The objective is to achieve good installation plasticity, rather than low water contents.

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5.0 INSTALLATION:

Prior to hand placing ACTCHEM into hexmesh or other anchorage systems, they should be properly installed to specification and free from grease. The ACTCHEM should be rolled into a sausage shape and installed by pressing into location with the thumbs, until the material is seen to flow through tabs, slots and under anchor systems, until the full thickness is achieved. This can be quickly achieved by the use of rubber mallets or pneumatic ramming hammers. Cut off excess material and then smooth the surface with a hardwood block and by gloved hand rubbing, until the desired finish is achieved. Excess material may be re-used. Always fill the hexmesh openings to full thickness. If installation is delayed, all surrounding openings must be cleaned, only full “biscuits” should be allowed to set. The material should not be subjected to water contact for 24 hours after installation, as this may affect the bonding system.

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6.0 TEST SAMPLE PREPARATION:

Samples can be taken using a “shoe box” mold (114 x 114 x 229 mm) for field installations. The molds shall be made of wood, plastic or steel and should be filled one third at a time, by filling all voids and achieving proper compaction. If a releasing agent is to be used, then it should be free of hydrocarbons, phosphates and carbonates. Mechanical installation devices can be used and all completed surfaces must be smooth. Samples shall be air dried between 21 and 32ºC for 24 hours, undisturbed. The “shoe box” sample can be cut to test size after 24 hours, using a dry saw blade. Sample should be heat dried


GUNITE INSTALLATION

ACTCHEM® is supplied in either plastic drums or bags as a one component mix containing aggregates and binder. ACTCHEM® ESL (Extended Shelf Life) consists of two dry components that are blended in the field prior to placement.

Installing Contractors are required to undertake a qualification program for the installation of ACTCHEM®85 by Gunning. ACTCHEM® is not difficult to gunite, but there are procedures that need to be followed to achieve the resistance to abrasion that is desired when using this product.

The mixing and control of the gunning of ACTCHEM® is critical to its performance and particular attention should be paid to the following procedures:

1.0 MIXING EQUIPMENT

1.1 Only paddle mixers in good, clean, working order are permitted for use. A paddle mixer with a drive that has 32 - 50 RPM's is recommended for mixing with the pre-dampening water.

1.2 Paddles must show no wear, clean and within 1 mm of drum surface.

1.3 The mixing action and capacity must be adequate to give vigorous agitation to prevent the formation of balls of refractory.

1.4 A polyethylene sheet should be available to prevent the loss of fine materials into the atmosphere, when mixing.

1.5 If Actchem ESL is used, premix aggregate and binder in mixer and mix for 1 min. and
follow normal procedures.

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2.0 PRE-DAMPENING WATER ADDITION

2.1 The water should be clean and free from contaminates. Potable water is required.

2.2 The 2% (Actchem 85) or 3% (Actchem 45/75) by weight water addition should be added as a spray, such as from a sprinkling water can and should be added directly into the castable while the mixer is turning. This will promote even hydration and help to prevent the formation of balls of wet refractory.

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3.0 GUNNING EQUIPMENT

3.1 The gunning machines should be set-up to provide minimum flow of product through the hydration nozzle. Two chamber guns should be operated at their slowest motor speed, Reed guns should be fitted with the 30 pocket shallow feed bowl and Meynadier machines should have the half-sized drum fitted operated at low speed.

3.2 Either 25 or 38mm I.D. hoses can be used.

3.3 The hydration nozzle is critical to achieve the best installation. The nozzle should be fitted with a needle valve control water tap. The nozzle type must not be a straight pipe type, as it does not provide good hydration mixing. It is recommended that a 400 mm long extension hose be attached after the water body, and then a rubber tip is attached (double bubble or boulder type), to create the turbulence necessary to provide good hydration

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4.0 OTHER EQUIPMENT

4.1 Proper dusk masks and eye protection should be used by all mixing and
installation personnel.

4.2.1 An accurate water-measuring metering device is required.

4.3 Trowels for cutting level and hardwood blocks for finishing the surface can be used.

4.4 Clocks to measure mixing times are required for each mixer or mixing station.

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5.0 GUNNING PROCEDURES

5.1 Fill the mixer to 80% capacity, cover with the polythene sheet, and dry blend the standard single component ACTCHEM for 30 seconds. The two components ACTCHEM ESL should be combined and mixed for two minutes.

5.2 Spray in the 2% water directly into the mix and mix for a further two
minutes. Even disbursement of water is important.

5.3 Empty the pre-dampened product from the mixer to a storage area and pre-set for 15-20 minutes.

5.4 Fill the gun with regular additions of product - do not overfill, as this can cause "bridging".

5.5.1 Use a slightly higher than normal air pressure may be required and rotate the gun motor at a minimum speed to achieve the desired production and control objectives.

5.5.2 The product should be gunned vertically to the vessel wall, particularly when gunning into enclosed anchor systems, such as hex metal.

5.5.3 The rate of installation at 25mm thick linings should be about 5-7 minutes per square meter. i.e. the product should be "painted" onto the vessel wall.

5.6 The water addition should allow the product to flow into the corners of the anchor systems.

5.7 Rebound losses are extremely low. Excessive water should be avoided, as this will affect the
performance of the finished product.

5.10 Gun the lining to just under the desired thickness, scrape off any product build up on the anchor system, then slightly over shoot the desired thickness by 2-3mm.

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6.0 FINISHING THE LINING SURFACE

6.1 Wait until the material begins to set, then cut the lining to the desired
thickness profile. When using cut off materials, if necessary, fill in voids and hollows and trowel or rub with hardwood blocks to the desired finish.

6.2 It is not necessary to polish the surface to achieve the desired erosion loss
results. The gunning of ACTCHEM® should be viewed as a method of transporting the product in a fast effective manner to the vessel surface.

6.3 It is recommended that 4-6 finishers would be required to maintain
continuous production, when gunning 25mm thick linings.

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7.0 SAMPLE PREPERATION

7.1. Provide a wooden box measuring 300mm X 300mm X 100mm Deep.
(12in X 12in X 4in deep)

7.2 Coat inside of box with release agent free of hydrocarbons, phosphates and carbonates

7.3 Gunite the box full during actual application of the lining taking care not to produce any material entrapment.

7.4. Cut material back to box thickness.

7.4 Air dry for 24 hours at proper temperatures.

7.5 Test per ASTM procedures by cutting samples from box. Report any voids found in
sample.

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