Cooling Method
Expanded rubber seals are made of rubber material and can be shrunk by cooling. Place the seal in a sealed bag and put it in the refrigerator; it will gradually shrink. This process takes some time, typically ranging from a few hours to a full day.
Heating Method
Contrary to the cooling method, heating can also shrink an expanded rubber seal. Place the seal in a suitably sized container, such as a pot or an oven-safe dish. Add enough water to completely submerge the seal. Bring the water to a boil and let the seal soak in the boiling water for a few minutes. Exercise caution during this process to avoid burns.
Compression Method
Place the seal between the jaws of a clamp or between two wooden boards, apply sufficient pressure, and hold it in place for several hours. Then, remove the clamp or boards and gently extract the compressed seal by hand. While this method effectively reduces the seal's size, care must be taken to preserve its shape and avoid damage.