Pronal products

The STP flexible separators for transformers, also known as “bladders”, “aircell” or “compensation balloons”, protect the dielectric oil in the power transformers. By compensating for their variation in volume, the STP handles the separation between the air and the oil inside the hydraulic conservator. This way the dielectric oil is protected from outside contamination. Our compensation bladders are custom made (material, shape, dimensions, flange and mounting feed). Their tightness to gas, oil, and water as well as their high mechanical resistance make Pronal STP Bladders a high performing system to protect your electric power transformer.