The D4 is engineered for reliable product separation in hygienic applications, using double-seat mix proof technology to prevent cross-contamination while allowing simultaneous processing and CIP. Its cleanability, durability, and efficient operation make it well-suited for food, beverage, and dairy systems.
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D4 Series: Mixproof Valves
The D4 Series Mix Proof valve offers reliable separation of fluids and an ultra-hygienic option for enhanced cleanability. This next generation of mixproof valve technology is the result of continued development from both APV and Waukesha Cherry-Burrell process technologies.
Used for the reliable separation of dissimilar fluids, the D4 Series helps fulfill today’s customer demands for production flexibility, increased productivity, rapid return on investment (ROI), and improved product quality across the Food & Beverage, Dairy, Personal Care and Brewing process industries.
D4 Double Seat Mixproof Valves
Key Features & Benefits:
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High value, Low life cycle costs:
- Tiered model range helps to increase ROI and align with customer budgets
- "All In" standard features provide exceptional value
- Reduced inventory costs with same seal kit used on multiple size ranges such as one kit for 1.5" - 3.0" sizes
- Reduced CIP losses improve cost savings
- Low air consumption and air supply requirements
- Long housing ports ease manifold building
- Integrated shaft seal flush reduces need for external piping
- Replacement insert available to easily upgrade existing installations
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Reliable performance:
- Fully balanced design helps to prevent hydraulic blocking, withstand pressure spikes, and enables flexible flow direction without slamming
- Light overall weight helps support handling without lifting tools
- Slim stainless actuator is fully enclosed to prevent fluid ingress
- Range of control units and bus communication for automated operation
- No compressed air needed for removal and servicing
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Cleanability:
- Designed to the latest hygienic standards
- Standard cavity spray cleaning
- Extensive cleaning of product contact seals
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Theory of Operation: Mixproof Valves
Mix proof valves are used to safely and efficiently process two different fluids (typically product and CIP) through the valve simultaneously. The mix proof design has two seats which isolate the upper and lower pipe lines when the valve is in the fail-safe closed position. The atmospheric vent cavity in between the seats creates a path for any leakage should the seats fail as well as a drain for CIP solution during seat cleaning. An optional external flush is available to clean the area between the seats and the vent drain while the valve is closed during production.
D4 Mixproof Valve Overview
This video explains how the double-seat technology ensures safe product separation, reliable CIP performance, and efficient operation in sanitary processing systems.
Frequently Asked Questions
With its robust actuator design, simplified maintenance features, and superior internal cleanability, the D4 minimizes downtime and supports continuous production runs. The valve’s geometry ensures repeatable performance and reduces the risk of CIP-related failures.
Yes. The D4 incorporates maintenance-friendly components, including removable seats and accessible internals, allowing technicians to service key elements quickly. Its hygienic design also reduces cleaning complexity and supports consistent long-term reliability.
The D4 is the next-generation evolution of prior Waukesha Cherry-Burrell and APV mix proof valve technologies. It enhances performance through improved seat design, updated actuation, superior cleanability, easier maintenance, and expanded configuration options for modern processing demands.
