Foundry bentonite is in-organic treated bentonite clay which is utilized in foundry to bind the sand grains into desired shapes. It helps in retaining the mechanical shape of the mould by making the particles of sands adhere to it and also making the surface impermeable. Strength and fusion point are the two important properties desired for selecting bentonite. Primary use is in the production of non-ferrous castings. Mixing ratio depends on the sand fineness and its quality, impurities, clay particles and fineness of sand will affect the Green strength properties.
Typical properties:
Properties Sodium Base Bentonite Calcium Base Bentonite
CP-FCA CP-FNA1 CP-FNA2
Methyl blue g/100g ≥ 32 32 30
Colloid value ml/15g ≥ 500 400 48
Swelling value ml/g ≥ 50 20 10
pH value 8.0-9.5 8.0-9.5 6.5-7.5
Wet pressure strength Kpa ≥ 50 40 30
Hot wet tension strength Kpa ≥ 3.0 2.0 1.5
Moisture% ≤ 10 10 10
Fineness(pass 200mesh screen) ≥ 95 95 95
Advantages and Applications:
CP-FNA1 is sodium bentonite with high thermal stability; It has advantages of small dosage (addition level is less than 5%), high wet pressure strength, high hot wet tension strength, nice gas permeability, good recycling. It is suitable for high precision casting.
CP-FNA2 is normal sodium bentonite; CP-FNA2 has nice gas permeability and. Good recycling, its dosage is about 5%-8%. It is main selection for precision casting and normal casting.
CP-FCA is calcium bentonite. It is suitable for normal casting and rough casting, it is main selection for rough casting.
Packing:
25kg/bag, 50kg/bag, 1000kg/bag.