Fume Hood - Sash Counterbalance Systems

Sash Counterbalance Systems

• Cable & Pulley Systems - Typically an aircraft grade stainless steel cable runs over independently positioned pulleys to the counterweight. Cable counterbalance systems can bind when a user lifts the sash from one end of the hood, as the cables will travel across the pulleys at different rates. This system requires regular maintenance as the cables will fray or break over time.

• Chain & Sprocket Systems - Typically a hardened chain (similar to a bicycle chain) runs over sprockets to the counterweight. The sprockets are attached onto a single axle which allows them to turn at the same time. This system will travel smoothly no matter where the user chooses to lift the sash along the hood width. This is especially important on longer hoods where the user may be lifting the sash at one end. This system has an indefinite lifespan with little to no maintenance.