General Overview

This technical document provides detailed specifications, installation instructions, and performance data for the Praher Plastics K6 wafer-type check valve made primarily from PVC materials. It covers valve design, materials, dimensions, operating conditions, and maintenance recommendations.

1. Specifications and Materials

• Valve Type: Wafer-type check valve K6.
• Materials: PVC (Polyvinyl Chloride) for body and flap; optional stainless steel (AISI 316) or Hastelloy C-4 for springs and shafts.
• Seals: EPDM or FPM O-rings depending on application.
• Pressure Ratings: PN6, PN10, PN16 depending on size and material; maximum operating pressure up to 10 bar.
• Temperature Range: Up to 60°C for PVC valves.
• Standards: Flange dimensions conform to DIN 2501 and ANSI standards; pipe compatibility includes PE100 SDR17 and PVC PN6/PN10.

2. Dimensions and Sizes

The valve is available in nominal diameters (DN) from 20 to 300 mm (approximately 1/2" to 12"). Detailed dimensional tables specify key parameters such as diameter (d), length (B), flange dimensions (LK DIN, LK ANSI), and opening angles (W). These dimensions ensure compatibility with standard piping systems and stub flanges.

3. Operating Features

• Opening Angle: The flap opens between approximately 62° to 90°, depending on size.
• Spring Mechanism: Integrated spring ensures reliable flap closure and prevents backflow; spring materials vary by application.
• Pressure Loss and Flow Characteristics: Pressure loss data and flow rates are provided for different DN sizes, measured at 20°C with water as the medium. Opening pressures range from 10 to 20 mbar depending on valve size.

4. Installation Instructions

• Valves are designed for wafer installation between flanges without the need for machining.
• Proper centering of the valve body and flap is critical to ensure optimal function.
• Flap clips must be checked before and after installation to ensure they are secure and undamaged.
• Bolts should be tightened in a diagonal sequence to recommended torque values (ranging from 15 Nm for DN40 to 45 Nm for DN300) to ensure even sealing and avoid damage.
• Installation is suitable for both horizontal and vertical pipelines, with recommendations to verify flap opening and closing after installation.

5. Maintenance and Safety Recommendations

• Regular inspection of flap clips, seals, and springs is advised to maintain valve performance.
• Valve components such as O-rings and springs are replaceable; kits are available for maintenance.
• Transport and storage should avoid damage to the flap and sealing surfaces.
• The document emphasizes that the product range is subject to technical modifications and upgrades, and users should consult the latest data before installation.

6. Technical Diagrams and Data Tables

The document includes exploded views of valve components, pressure loss diagrams, and torque tables. Key data extracted include:

• Pressure loss vs. flow rate curves for various DN sizes.
• Opening pressure values required to initiate flap movement.
• Torque specifications for bolt tightening to ensure proper flange sealing.

Critical Information Summary

• Valve K6 is optimized for PVC piping systems with pressure ratings up to PN10 and temperatures up to 60°C.
• Correct installation with proper bolt torque and flap clip verification is essential for reliable operation.
• Material options for springs and seals allow adaptation to different chemical and mechanical requirements.
• Regular maintenance and inspection extend service life and prevent operational failures.

Note: This summary is based on the provided technical data and is intended for informational purposes only. Users should refer to the official Praher Plastics documentation for detailed engineering and safety guidelines.