Skip to main content

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.


Squeezer Machine





Comments

Popular posts from this blog

Advantages And Disadvantages Of Air Refrigeration System :

 Advantages Of  Air Refrigeration : 1. The refrigerant used namely air is cheap and easily available. 2. There is no danger of fire or toxic effects due to leakages. 3. The weight to ton of refrigeration ratio is less as compared to other systems. Disadvantages Of Air Refrigeration : 1. The quantity of  Refrigerant used per ton of refrigeration is high as compared to other systems. 2. The COP of the system is very low. Therefore running cost is high. 3. The danger of frosting at the expander valves is more as the air contains moisture content. 

MELTING FURNACES FOR FERROUS METALS : CUPOLA AND ITS WORKING

Various types of melting furnaces are used in different foundry shops, depending upon the quantity of metal to be melted at a time, and the nature of work that is carried out in the shop.  The primary objective in cupola is to produce iron of desired composition, temperature and properties at the required rate in the most economical manner. Besides, this furnace has many distinct advantages over the other types, e.g., simplicity of operation, continuity of production, and increased output coupled with a high degree of efficiency.  Description Of a Cupola : The Cupola Furnace consists of a vertical, cylindrical steel sheet, 6 to 12 mm thick, and lined inside with acid refractory bricks or acid tamping clay. The refractory bricks or the tamping clay used consist of  silicon oxide acid (SiO2) and alumina (Al2O3). The lining is generally thicker in the lower where the temperatures encountered are higher than in the upper region. The shell is mounted either on a brick work fo...

SIMPLE CARBURETOR - CONSTRUCTION AND WORKING

CONSTRUCTION OF SIMPLE CARBURETOR :  The main Components of Simple Carburetor are : Float Chamber, float, nozzle, venturi, throttle valve, inlet valve, and metering jet . In the float chamber, a constant level of petrol is maintained by the float and a needle valve.  The float chamber is ventilated to atmosphere.  This is used to maintain atmospheric pressure inside the chamber. The float which is normally a metallic hollow cylinder rises and closes the inlet valve as the fuel level in the float chamber increases to certain level. The mixing chamber contains venturi, nozzle and throttle valve. The venturi tube is fitted with the inlet  manifold. This tube has a narrow opening called venturi. A nozzle is provided just below the centre of this venturi. The nozzle keeps the same level of petrol as that of the level in the float chamber. The mixing chamber has two butterfly valves.  One is to allow air into the mixing chamber known as choke valve. The other is to al...