Since 1935 Scully has been setting standards in tank filling safety. Our systems provide static grounding protection, prevent spills, and ensure safe loading in everything from rail tank cars, tank trucks, and storage tanks. There are a number of different options available to ensure safe transfer of hazardous liquids into rail tank cars.
Static Ground Proving Systems
The Scully Groundhog® Static Bonding Control Unit with Junction Box and Grounding Plug or Clamp, provides an electrical bond to ensure that the vehicle is at the same ground potential as the loading rack. Only Scully offers a special “smart” Ground Ball that when mounted on the tank vehicle, provides absolute assurance that the Grounding Control Unit is connected to the tank car. For railcars where the ball is not permanently mounted, a clamp is available. The clamp provides a resistance (non- self-proving) verification system.*
Overfill Prevention Systems
For extra loading safety, Scully also offers the ST-15 Overfill Prevention Control Unit and portable Cane Sensor for top loading spill protection. For multiple, single compartment tank cars, specify one Control Unit and Sensor per tank car.
*Warning: Attaching a clamp to a metallic object or vehicle which already has a return path to ground, may provide a false permissive indication. For maximum safety and self-proving safety, specify Scully Groundhog with ground plug and vehicle-mounted Scully Ground Ball.

Typical Single Compartment Application; for additional configurations, contact Scully Applications Engineering.
Scully Systems are designed to meet industry Recommended Practices, Regulations and Codes:
- API Recommended Practice RP 1007
- EPA SPCC 40CRR Part 112
- National Fire Protection Code NFPA 30 & 30A 28.2.1.2
Literature/Downloads:
Railcar Brochure: Scully Loading Solutions for RailCar_Brochure.pdf
Case Studies:
Sulphuric Acid Loading Applications for Railcars
Safety & Efficiency Case Studies
Technical Data Sheets:
Groundball Groundbolt_67037_RevF_BE_ATEX_German.pdf
Groundball Groundbolt_67037_RevF_BE_ATEX.pdf
Groundball Groundbolt_67037_RevF_UK_ATEX.pdf
Groundball Groundbolt_67037_RevF.pdf
Plug and Cable Assembly with Sculcon Series Junction Box_60614_RevF_ATEX_German.pdf
Plug and Cable Assembly with Sculcon Series Junction Box_60614_RevF_ATEX.pdf
Plug and Cable Assembly with Sculcon Series Junction Box_60614_RevF.pdf
Portable Liquid Level Sensors_60632_RevE.pdf
ST47C_67221_RevD_EU_BE_French.pdf