Coal sizers tooth plate, material, in a group of 6 pieces, wrapped in a circle, rolling the material. Although the impact is not large, but because of the request of crushing particle size is fine and uniform, the design and use surface is nail shape (as shown in Figure 1), unique shape, wear, request has a high precision of wool and casting teeth quality. 1, sand analysis: from the shape and high precision installation can be seen, the selection of ordinary clay sand, because the repair is difficult and can not ensure the shape of the tooth surface and installation accuracy, the choice of hard sand. Our section commonly used self-hardening sand is quartz sand as the main material of C02 sodium silicate sand, because it is acidic sand, easy to produce chemical sand in high manganese steel forging, need to brush thick manganese steel paint to deal with. And we can see that some teeth not only lack a good brush, and it is easy to form difficult to clean up the coating accumulation at the tip of the teeth, and then make the products after pouring teeth are not full. Therefore, we should try to choose the same alkaline sand with high manganese steel to avoid thick brush paint.
Such sand mainly chromite ore and magnesium olivine sand. Chromite ore particle size is fine and uniform, has high molding ability and fire resistance, and then easy to get high surface quality, high scale precision casting. But its price is expensive, a lot of use will form a high cost of casting production. And magnesium olivine sand, because the particle roundness is poor, the particle size is uneven, so the molding can be poor; Its fire resistance is also lower than that of chromite ore (higher than quartz sand). But because of its relatively low price, it is more widely used in high manganese steel forging. Therefore, the primary selection of magnesia olivine sand as the main material in this trial production of C02 sodium silicate sand. The mud core of the four mounting holes uses chromite ore as the main material of C02 sodium silicate sand.
Parting surface: according to the structure, this part of the parting surface is only selected in the root arc surface, plan one is the tooth face up, plan two is the tooth face down. The tooth upward is not only not easy to fill, and because it is not easy to tie air holes in the hard sand, the formation of cavity tooth exhaust is difficult and the lack of pouring. Make the degree of fullness of the cast teeth is not good. So should choose teeth face down;
Riser: According to the structure, this riser is difficult to be polished by gas cutting on the top surface, and high manganese steel is paste condensation, so it is more suitable to choose side riser. Therefore, two side risers are selected to be placed on two end faces, which is conducive to feeding and gas cutting grinding:
Wood type: strictly request wood type scale precision. Another thing to note is to make a living block of teeth nail, the direction of the pin must be perpendicular to the parting plane rather than the arc surface, in order to ensure that it does not hinder the mold;
Paint: Coal sizers choose magnesium olivine alcohol paint. Note that to avoid the accumulation of top grade paint on the nails, the paint should be light here and may not be used when it is difficult to handle. 2. After user information feedback, installation and use function are particularly good. 1. C02 water glass self-hardening sand of magnesium olivine sand is very suitable for forging small and medium-sized pieces of high manganese steel with high scale precision, smooth surface, more sharp corners, small grooving and other structures that are not easy to brush paint:
For Coal sizers of the small deep holes, small deep gully, etc., the C02 water glass self-hardening sand of chromite ore is selected. This can better ensure the forging accuracy and avoid the burning of molding sand. 3. The fine pointed edge structure of castings should be adopted as far as possible in the self-hard sand forging, so as to ensure the structural shape and fullness of pointed edge.