The bucket teeth are made of resin sand, the shovel head is made of non sun casting technology, and the shovel seat is made of riser and cold iron. Because the shovel head and shovel seat are used in the blank state, it increases certain difficulty for casting production. The shovel head and shovel seat should be interchangeable, that is, the newly manufactured shovel head can not only be interchangeable with the new shovel seat, but also cooperate with the old shovel seat, and the matching size must be guaranteed. If the fit clearance is too large, it will be seriously worn in use, and the shovel seat will be worn out quickly. Because the shovel seat is generally not replaced frequently, we strictly control the mold size and the thickness of coating in production, and specially made a special test sample.
Use 0.15t medium frequency electric furnace for melting and start low-power power transmission. Gradually melt with full power transmission to shorten the melting time as far as possible, so as to reduce the melting loss of various elements and the oxidation of molten steel. Slag forming agents such as broken glass are used for liquid steel slagging, and low-carbon ferromanganese and ferrosilicon are added for deoxidation in the furnace. Thermocouple type electronic thermometer for temperature measurement; Molten steel melts to 1620 ℃; The final deoxidation is carried out with pure aluminum wire in the ladle, and the test block is poured before pouring. See table for smelting loss of each element.
| Element | C | Si | Mo | Cu | Nb |
| Smelting loss rate | 10 | 10 | 5 | 5 | 5 |
In addition, the pouring temperature directly affects the forming and internal quality of the casting. It is easy to stick sand and produce shrinkage cavity if it is too high. Due to the uneven thickness of the bucket teeth, it is the key to determine the reasonable pouring temperature. After many pouring tests, the pouring temperature is finally determined as 1520-1530 ° C。