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Baffle blades for cooling have traditionally been made of brass. Trouble is, brass has significant drawbacks that make it difficult to achieve maximum heat transfer. Fortunately, a new material—polypthalamide—offers a dramatic improvement in the performance and features for baffle blades used in plastic injection molds. Check out a side-by-side comparison video.

Pictured on the right is a side-by-side comparison of traditional brass baffles and new turbulent flow plastic baffles.

Baffles are used to force water up bored holes to deliver cooling water as close to the part surface as possible.

Traditional Trouble
Brass baffle blades tend to have about 0.20” clearance on each side to allow the blade to be screwed into the threading at the end of the gun-drilled cooling channel.

The problem is that coolant flowing through the channels will naturally use this gap as the preferred route of travel, creating blow-by on each brass baffle blade. Typically, the only way to combat blow-by and improve cooling is to add more water lines or larger pumps to increase flow.

Go with Better Flow
New plastic baffle technology offers a tremendous advantage because plastic allows the baffle to touch and create a seal with the sides of the coolant channels.

By eliminating the gap on the side of the blade, coolant flows closer to the top of the cooling channel and closer to the part. The result: better cooling.

The Advantage of Turbulent Flow Plastic Baffles
Made entirely with glass reinforced polypthalamide, D-M-E turbulent flow plastic baffles create turbulence within the cooling channel to increase heat transfer and cool parts faster.

In D-M-E’s patented design, the face of the plastic baffle has a raised flowing rib pattern that travels, without interruption, the length of the blade face on both sides—creating the coveted coolant turbulence.

Turbulent flow plastic baffles promote uniform flow of coolant and seal tightly within the mold’s cooling channels to ensure uniform cooling. They perform well even in high heat production environments.

The impressive results include:

• Stagnant laminar flow cooling nearly eliminated
• Three times the BTUs dissipated
• “Hot core” syndrome greatly reduced
• ΔT lowered across the mold surface
• Coolant wall velocity increased
• Overall cycle times cut by up to 20%