AquaMatic K520-111 1/2-Inch Retaining Ring & Nut Assembly with Viton Seals (Pair)

Secure your piping manifolds with confidence using the Genuine AquaMatic K520-111 Retaining Ring & Nut Assembly Pair (SKU: 1079555). Manufactured by AqMatic (formerly Pentair), this high-strength installation hardware set is specifically engineered to mount end adapters securely to 1/2-Inch K520 Series Composite Body Diaphragm Valves.

Featuring rugged metal construction paired with premium Viton gaskets, this assembly is designed to withstand higher mechanical stress, elevated operating temperatures, and aggressive chemical environments where standard components might fail.

🛠️ Core Application & Compatibility

Essential Installation Component: This assembly is required to connect and seal end adapters—such as the K520-PC (Solvent Weld) or K520-P (NPT Threaded) pairs—directly to the valve body. By utilizing this matching metal pair, you establish a true union-style connection that allows for effortless in-line servicing and quick valve isolation.

Key Features & Benefits

• High-Strength Metal Construction: The heavy-duty metal retaining nuts provide superior mechanical strength, preventing thread stripping or cracking when torque is applied during high-pressure manifold installations.

• Premium Viton (FKM) Face Seals: Equipped with top-tier Viton O-rings to deliver maximum resistance against aggressive chemicals, acids, caustics, and thermal degradation.

• Streamlined Valve Servicing: Enables a secure union joint configuration. Simply loosen the nuts to slide the valve completely out of the piping line for maintenance without cutting or dismantling your pipework.

• Sold as a Complete Matching Pair: Every package includes two nuts, two retaining rings, and two Viton gaskets—providing everything required to fully outfit both the inlet and outlet ports of a single 1/2" K520 valve.

Comprehensive Kit Parts List

The K520-111 Pack is supplied as a complete dual-port installation set. Each kit contains:

• 2 x Metal Union Nuts (Item No. 20): Heavy-duty threaded rings that pull the end adapters flush and square against the valve body.

• 2 x Retaining Snap Rings: Splined split-rings that lock into the adapter grooves to distribute locking pressure evenly.

• 2 x Viton Face O-Rings: High-performance chemical-resistant gaskets that sit between the adapter and the valve face to ensure a drip-tight seal.

Technical Specifications

Professional Installation Advice

When assembling your valve manifold, slide the metal union nut onto the pipe or end adapter before making your final pipe connection (solvent weld or threaded). Position the retaining snap ring into the adapter groove, place the Viton face O-ring into the valve body recess, and thread the nut onto the valve body by hand.

Tighten firmly to ensure the face seals seat perfectly square. For internal valve maintenance down the line, remember to use the specialized AquaMatic 520-Z Assembly Tool to safe-keep your internal thermoplastic threads during teardown.