Hot Topping
Hot toppings are added to the tops of risers and pouring cups to help improve the efficiency of the riser. Hot toppings are either exothermic, insulating, or a combination of both. Hot toppings generate heat to help aid in the feeding of the casting. Once the exothermic reaction has finished, the crust formed causes an insulating effect preventing heat loss, improving piping, and effectively feeding the casting.
We offer a range of exothermic, insulating, and metal-producing powder hot toppings. In addition, we provide hot toppings for ferrous and non-ferrous alloys. With various times for ignition, rate of burn, and amount of smoke generated, we have an option that will work for you.
| Name | Time for Ignition | Rate of Burn (mm:ss) | Smoke | Odor | Crust or Expanding | Density | Exothermic, Insulating, or Metal Producing | Ferrous or Non-Ferrous |
|---|---|---|---|---|---|---|---|---|
| Exotop 500 | 4-5 sec | 01:25 | MED | LOW | Crust-Hard | 70-80 Density | Exothermic | Ferrous |
| Exotop 100B | 7-8 sec | 01:50 | MED | LOW | Crust-Hard | 80-90 Density | Exothermic | Ferrous |
| Expandex 500 | 3-4 sec | 01:50 | MED | LOW | Expanding-Soft | 60-70 Density | Exothermic | Ferrous |
| Expandex 544 | 3-4 sec | 01:15 | LOW | LOW | Expanding-Medium | 57-59 Density | Exothermic | Ferrous |
| Expandex 544S | 5-6 sec | 01:30 | LOW | MED | Expanding-Medium | 55-65 Density | Exothermic | Ferrous |
| Exotop 100 | 7-8 sec | 01:10 | MED | NONE | Crust-Hard | 80-90 Density | Exothermic | Ferrous |
| Exotop 300S | 6-7 sec | 01:35 | LOW | MED | Crust-Hard | 60-70 Density | Exothermic | Ferrous |
| Exotop GLS | 3-4 sec | 00:40 | MED | LOW | Expanding-Soft | 55-65 Density | Exothermic | Ferrous |
| Exotherm 100 | 0-2 sec | 02:00+ | LOW | LOW | Crust-Hard | 47.5-52% Yield | Metal Producing | Ferrous |
| Exotherm 150 | N/A | N/A | N/A | N/A | N/A | 48-51% Yield | Metal Producing | Metal Producing |
| Exotherm 190 | 3-4 sec | 02:00+ | LOW | LOW | Crust-Hard | 47.5%-51% Yield | Metal Producing | Ferrous |
| Insultop 100 | 0-2 sec | 00:45 | NONE | NONE | No Change-Soft | 32-36 Density | Insulating | Ferrous |
| Insultop 105B | 0-2 sec | 00:45 | NONE | NONE | No Change-Soft | 32-36 Density | Insulating | Ferrous |