Mermade 26" Round, 4-3/4" Hub, Zipper Closure (Swimquip Replacement), Cover Only

The Mer-Made 26" Round, 4-3/4" Hub, Zipper Closure (Swimquip Replacement) — Cover Only (cataloged under Part # 775-COVER / VFC-26R-SQ-4.75) is the replacement circular fabric filter jacket designed to re-cover existing bare plastic disc cores in commercial vacuum and pressure DE filtration systems retrofitting legacy Swimquip (SwimQuip / Sta-Rite / Pentair) equipment.

This configuration is engineered specifically for Swimquip circular leaf banks that utilize a heavy 4-3/4" outer diameter center hub pass-through opening. It supplies only the tailored circular woven synthetic filtration cloth envelope, heavy-duty circumferential marine-grade zipper, pre-cut and bound center hub collar, and paired hub compression sealing gaskets. It is specified when the internal radial drainage matrix disc and rigid thermoplastic perimeter rim remain structurally sound, but the existing jacket has blinded from calcified DE, body oils, or mineral scaling, or has suffered physical tears.

Technical Specifications & Scope of Delivery

Material Properties & Chemical Tolerances

• Chlorine & Saline Resistance: Virgin woven polypropylene fibers resist degradation, rot, and hydrolysis under continuous exposure to elevated free chlorine levels, hyperchlorination shock treatments, and saline electrolytic pool water (2,500 to 5,000+ ppm NaCl).

• Acid Wash Survivability: Withstands routine seasonal chemical descaling baths in dilute muriatic (hydrochloric) or citric acid solutions to dissolve embedded calcium carbonate crust, iron staining, and organic oils without deteriorating seam stitching or zipper teeth.

• Pre-Coat Retention & Release: The balanced monofilament weave structure retains standard DE powder and perlite grades without bleed-through during initial pump startup, while facilitating clean cake release during backwashing or manual hose-down.

Physical Dimensions & Weight Estimates

• Individual Cover Net Weight: Approximately 0.60 to 0.85 lbs (0.27 to 0.39 kg).

• Single Boxed Cover Shipping Weight: Approximately 1.50 to 2.20 lbs (0.68 to 1.00 kg) in a compact corrugated carton.

• Master Carton / Multi-Pack (6 to 12 Covers): Approximately 6.0 to 11.0 lbs (2.7 to 5.0 kg).

• Full Bank Overhaul Pack (15 to 30 Covers): Approximately 14.0 to 25.0 lbs (6.4 to 11.3 kg).

Field Re-Covering & Tensioning Steps

1. Disassemble Center Hub: Remove the circular element from the manifold shaft. Unthread the Swimquip center hub compression ring/flange, slide off the spent cover, and discard the compressed hub gaskets.

2. Core Wash-Down & Inspection: Pressure-wash the bare radial drainage disc to clear trapped DE, sand, and scale. Inspect the plastic radial ribs and outer circular rim for cracks, warpage, or sharp flash that could snag or cut the replacement fabric.

3. Position Replacement Jacket: Unzip the 26" perimeter marine zipper completely. Lay the core inside the bottom circular fabric panel, aligning the central 4-3/4" opening with the core's center hub collar.

4. Close & Tension Perimeter: Fold the upper fabric face over the disc. Smooth the cloth radially outward from the center hub toward the rim to eliminate ripples, then pull the marine zipper slider completely around the 26" circumference.

5. Secure Zipper Pull: Tuck the zipper pull-tab flat underneath the protective fabric retention flap at the closure stop to prevent it from backing open during backwash agitation.

6. Reinstall Center Compression Hub: Fit fresh neoprene/EPDM or felt gaskets on both sides of the 4-3/4" center collar cutout. Reinstall the Swimquip hub clamping flange and torque down evenly to create a positive seal that prevents DE bypass around the manifold shaft.