For large shot sleeves, cooling is usually required to reduce the maximum temperature. Preheating the shot sleeve before the pour will also reduce the amount of temperature differential. This can be done best by circulating oil at a temperature of about 400°F (205°C).
To maintain a constant oil temperature, CASTOOL provides Thermal Oil Temperature Control Units which can be operated either by the temperature of the oil itself, or by thermocouples in the sleeve.