Standard Sprue Bush Lengths

The length of a HotFlo! sprue bush is the distance from the bottom of the nozzle engagement seat to the die parting line, as shown.

Each HotFlo! Series is available in a number of standard lengths. Wherever possible, the design of the fixed half of the die should be based on one of these standard lengths. There are a number of ways in which a HotFlo! sprue bush can be incorporated into a die block, as described below.

Fixed Die Options

Option 1: Back Mounting Plate and Insulation Plate. This is a good solution for many dies because the back plate naturally captures and protects dowel pins, angle pins cores and inserts as well as creating a convenient clamping face. The insulation plate retains heat in the die.

Option 2: No Mounting Plates. Another option is to remove the Back Mounting Plate (and/or the Insulation Plate), and clamp the die directly to the fixed platen.

Option 3: Stepped Parting Line - Shorter. Some die cavities require a stepped parting line which reduces the required sprue bush length.

Option 4: Stepped Parting Line - Longer. Similarly, a deep offset on the other die half may result in a correspondingly longer sprue bush.