Monthly Archives - September 2019

SETCRETE AF

HIGH PERFORMANCE ALKALI-FREE SHOTCRETE ACCELERATOR

Shotcrete has been widely used in tunnel, underground, and marine works for providing early support and preventing water seepage. Key performance indicators of the shotcrete are setting time and strength, which are decided by not only mixture design but also the use of the accelerator. The accelerator alters the hydration mechanisms of the cementitious material, influencing its strength development and setting time.

However, most existing accelerators are types of alkaline powdery accelerator which will lead to caustic harm and dust pollution and dramatically cut down the long-time strength and the inhomogeneity of concrete. In order to solve such problems, FAIRMATE has developed SETCRETE AF, alkali-free liquid accelerators with advantages of high efficiency, high strength, and environmental friendliness have gained more and more attention.

SETCRETE AF has many advantages are as follows :
• The quick setting property allows rapid work progress and the ability to construct thick sprayed concrete linings via layered application during one construction sequence.
• The unique product formulation provides fast setting, continuous early-age strength development high durability and good long term strength.
• Very low dust generation during application and therefore a good working environment.
• Possibility of low rebound applications when using the correct nozzle angle and distance.
• Non-aggressive properties provide improved working safety, reduced environmental impact and lower handling costs.

SETCRETE AF is added undiluted at the nozzle. Normal dosage is 5-10% of the weight of the cement.In cold regions concrete can freeze before it gains strength which breaks up the matrix so for this reasons SETCRETE AF is recommended to accelerate the hydration reactions in concrete which allows it to gain early strength.

FAIRSEAL P – POURABLE GRADE TWO PART POLYSULPHIDE SEALANT

FAIRSEAL P is a two part, pourable, self levelling, polysulphide based joint sealing compound consisting of base compound containing a liquid polysulphide polymer and second part being an accelerator containing a curing agent. After mixing, the compound cures to form a tough, rubber like material with excellent flexibility and outstanding resistance to weathering water, salts, oils, mild alkalis etc.

FAIRSEAL P is suitable for sealing horizontal joints due to its pouring consistency. It has excellent adhesion to most surfaces including concrete, wood, glass, aluminum and stainless steel. For all porous surfaces like concrete wood, FAIRSEAL PRIMER is necessary.

ADVANTAGES

 Excellent weathering characteristics with resistance to rain, snow, heat & ultraviolet light
 It gets cured quickly with low shrinkage
 Accommodates continuous and pronounced cyclic movement
 Excellent adhesion to most common substrates
 High resistance to ageing influences, physical damage and climatic extremes
 Resistance to petrol, diesel, jet fuel and most other common solvents & also unaffected by mild acids and alkalies
 Forms a tough elastic rubber-like seal
 Pourable grade sealant for horizontal joints
 Long service life
 Maintenance free

JOINT SIZE
FAIRSEAL P may be applied to joints between 5 and 50mm. Minimum 5mm. depth is recommended for metals, glass and other smooth surfaces while minimum 10mm depth is recommended for concrete and brickwork surfaces. The use of a greater depth is recommended where resistance to external pressure is required, e.g. joints in floors and hydraulic structures. Ideally joints subject to regular movement should be designed with a width/depth ratio of 2:1.APPLICATION PROCEDURE

Surface Preparation
All joint surfaces should be thoroughly cleaned and dried and primed with ‘FAIRSEAL PRIMER’. Loose particles, dirt, dust, protective liquor, oil and grease should be removed by vigorous brushing with a wire brush and by means of suitable cleaners e.g. KEROSENE. After the primer is applied, it has to be relatively dried before sealant is applied. Deep joints should be back filled with a non retting backup material to which the sealant does not adhere eg. Closed cell polyurethane foam, which should be tampered into the joint to the required depth.

Application
FAIRSEAL P sealant is supplied in a pack with base and hardener (curing agent) in separate packing, ready for mixing. In order to mix both the compounds thoroughly it is preferable to use a slow speed electric mixer with suitable blades or paddles with a speed less than 300 RPM. Ensure thorough mixing till a uniform color is obtained. Failure of the sealant will often occur if it is not completely and thoroughly mixed. After mixing FAIRSEAL P may be poured directly into horizontal joints or loaded into the gun for application to horizontal joints less than 15mm wide.

Tooling & Finishing : To obtain a smooth surface, the sealant has to be tooled by drawing a flat tool, like a stainless steel spatula, over its surface. After sealing, the tools and equipments must be cleaned with KEROSENE.

ESTIMATION OF QUANTITY
To estimate quantities of sealant required, the formula given below can be used to calculate the number of (1 Kg or 5 Kg) tins needed. To calculate the weight (in Kg.) of sealant required for a joint of particular length (in meters), the following formula can be used.

Formula: Weight in Kg = (1.6 X W X D X L)/1000
Where W & D are in mm and L is in metre,
Example
W (Width of joint) = 10 mm
D (Depth of joint) = 10 mm
L (Length of joint) = 12.5 mtr

Weight in Kg
= (1.6 X 10 X 10 X 12.5)/1000 = 2 kg of sealant

1 Litre of FAIRSEAL Primer would cover 6 to 7 m² of joint area or about 1 litre of FAIRSEAL Primer would be required for 30 Kg of FAIRSEAL sealant.

PACKING
FAIRSEAL P is available in big packing of (4.600 kg base + 0.400 kg hardener) and small packing of (0.920 kg base + 0.080 kg hardener).