Squeezer Machine - Molding Machine And its operation

In the squeeze method, molding sand in the flask is squeezed between the machine table and the overhead squeeze board pneumatically or hydraulically until the mold attain the desired density.

The principle of operation of a top squeezer machine. The pattern 2 is placed on a mold board which is clamped on the table 1. The flask 3 is then placed on the mold board and the sand frame 4 on the flask. The flask and frame are filled with molding sand and leveled off. Next the table is raised by the table lift mechanism against the platen 5 on the stationary squeezer head 6. The platen enters the sand frame up to the dotted line and compacts the molding sand . After the squeeze , the table returns to its initial position.

As before the pattern is placed on the mold board which is clamped to the table. The flask 3 is placed on the frame 7 and is filled with sand. Next the squeeze head is brought against the top of the flask and the table with the pattern is raised upon the dotted line. After squeezing , the table returns to its initial position.

The main limitation of the squeezer method is that, the sand is packed more densely on the top of the mold from which the pressure is applied, and the density decreases uniformly with the depth. At the parting plane and around the pattern, the density is found to be lowest. This variation of density affects the hardness of the mold which thus varies according to the depth. The squeeze method is , therefore, restricted to molds not more than 150 mm in depth.

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