Sandpiper S20 Metallic Pumps
Spare Parts for Sandpiper S20 2" Metallic Air-Operated Double Diaphragm Pumps
Product Summary
Genuine OEM spare parts for the Sandpiper S20 2" metallic air-operated double diaphragm (AODD) ball valve pump, built in aluminium, cast iron or stainless steel and used across Australia for mine dewatering and sump duties, wastewater sludge, solvent and chemical transfer and general plant pumping at up to 758 L/min. Wet End and Air End Kits, diaphragms, check balls, seats, pilot valve and centre-section parts are all listed in the Sandpiper S20 parts list, so tick what you need and we’ll match them to your nameplate, such as S20B1ABBANS000.
Spare Parts List
✓ Tick the parts you need. Sandpiper S20 Metallic parts are matched to the pump's model code (wetted, diaphragm/valve and non-wetted material codes), so the full model number on your nameplate is all we need to get them right. Not sure which items? Add a photo of the nameplate and we’ll work it out for you.
| Select | Wear / Service Item | Function & when to replace |
|---|---|---|
| Common Service Kits | ||
| Wet End Kit | Sandpiper’s wetted overhaul set for the S20: two diaphragms, four check balls and four seats (with PTFE overlays on the overlay builds). Fit one when a diaphragm fails or flow drops from worn balls and seats. | |
| Air End Kit | Seals, O-rings, gaskets, retaining rings, the air valve sleeve and spool set and the pilot valve assembly in one pack. Order it when the S20 stalls, short-strokes or leaks air at the centre section. | |
| Diaphragm (item 16) | The flexing membrane that splits the air chamber from the liquid chamber on each side of the pump. Change both as a pair at the first sign of cracking, chemical attack or product in the exhaust. | |
| Check Ball (item 2) | The four balls that open and close the suction and discharge valves; weighted Nitrile, EPDM and Neoprene balls help on viscous products. Replace if undersized, flat-spotted or swollen, as they will stop seating. | |
| Valve Seat (items 37, 38) | The rings the check balls close against. Elastomer, PTFE and UHMW seats are item 37; aluminium, steel and stainless seats (item 38) each need two O-rings (item 41). Renew with the balls if grooved or eroded. | |
| Wear & Consumable Parts | ||
| Seat O-Ring / PTFE Seal (item 41) | Seals each seat between the outer chamber and the manifolds. Fit new ones whenever the manifolds come off, or sooner if the pump draws air on the suction side. | |
| PTFE Diaphragm Overlay (item 17) | A PTFE skin fitted over a Santoprene or Neoprene backing diaphragm for chemical resistance. Replace it alongside the backing diaphragm, and check it for creases or pin holes at every inspection. | |
| Diaphragm Bumper (item 6) | Cushions the inner plate at the end of each stroke on the diaphragm rod. Swap it if it has split or flattened, usually during a diaphragm change. | |
| Diaphragm Rod U-Cup Seal (item 36) | Seals the diaphragm rod where it passes through the intermediate bracket. A worn seal lets air bypass between chambers; Sandpiper suggests a full centre rebuild after any diaphragm failure. | |
| Pilot Valve Assembly (item 4) | Signals the main air valve to shift at the end of each stroke via the actuator plungers (item 33). Sleeve and spool O-rings are serviceable; replace the assembly if the pump stalls mid-stroke. | |
| Air Valve Sleeve & Spool Set (item 1-B) | The match-ground sleeve and spool inside the air distribution valve; the two halves are not interchangeable. Replace as a set if scored or if the pump cycles erratically. | |
| Air End Gaskets (items 19–22) | Gaskets 360.093.360, 360.114.360, 360.104.379 and 360.105.360 seal the air passages through the centre section. Fit new ones with holes correctly aligned whenever the air end is opened. | |
| Other Core Parts | ||
| Diaphragm Plates (items 28–32) | Inner and outer plates clamp each diaphragm to the rod. PTFE-overlay and one-piece bonded builds take their own plates; replace any worn to a sharp edge, as they will cut new diaphragms. | |
| Diaphragm Rod (item 35) | Links the two diaphragm assemblies so they stroke together. Replace if scored or marked, since rod damage wears out the intermediate bushings and rod seals. | |
| Outer Chamber (item 14) | The liquid-side chamber that houses the diaphragm and seats. Replace if eroded thin by abrasive slurry, corroded or cracked, matched to the wetted material code. | |
| Suction & Discharge Manifolds (items 23, 24) | The suction manifold (518.145 series) and discharge manifold (518.146 series) carry the ball valves and pipe ports. Replace if cracked or worn; welded flange versions (items 43, 44) are also listed. | |
| Intermediate Bracket (item 5) | The centre section carrying the rod, pilot valve and plunger bushings. Replace if the rod bores are worn oval; the 475-216-000 Midsection Conversion Kit swaps an aluminium centre for cast iron. | |
| Air Valve Assembly (item 1) | The no-lube main air distribution valve that directs compressed air to each side. Fit a complete assembly if the body is damaged; stroke indicator versions are 031.146.000 and 031.147.000. | |
How we confirm the exact part: Sandpiper S20 Metallic parts change with the wetted material, diaphragm and check valve material, seat material, centre-section (non-wetted) material, porting and hardware. Item and part numbers shown are as printed in the Sandpiper S20 Metallic service manual (Design Level 1); your nameplate carries the model code that sets those materials, e.g. S20B1ABBANS000 = ball valve, aluminium wetted, Nitrile diaphragms and balls, Nitrile seats, painted aluminium centre, NPT ports. Tick the items above and add a nameplate photo, and we’ll confirm the correct parts for your pump.
Models
Read the S20 model code from left to right: S (Sandpiper), 20 (2"), B or W check valve, design level 1, then the wetted material letter (A, X, I, S or H), the diaphragm/check valve code, seat code, non-wetted code, porting, style, pump option and kit option, e.g. S20B1ABBANS000. The builds below are the wetted materials in the S20 Metallic nomenclature.
Models & Key Specifications
| Diaphragm/valve code · or centre | Service kit | Diaphragm (item 16) | Check ball (item 2) | Seat in kit (item 37) |
|---|---|---|---|---|
| 1 Santoprene/Santoprene | 476-042-354 | 286.007.354 | 050.017.354 | 722.040.364 (EPDM) |
| 2 PTFE-Santoprene/PTFE | 476-042-654 | 286.007.354 + 286.020.604 overlay | 050.018.600 | 722.040.600 |
| B Nitrile/Nitrile | 476-042-360 | 286.007.360 | 050.017.360 | 722.040.360 |
| C FKM/PTFE | 476-042-633 | 286.007.363 | 050.018.600 | 722.040.363 (FKM) |
| E EPDM/EPDM | 476-042-364 | 286.007.364 | 050.017.364 | 722.040.364 |
| G PTFE-Neoprene/PTFE | 476-042-635 | 286.007.365 + 286.020.604 overlay | 050.018.600 | 722.040.600 |
| I EPDM/Santoprene | no kit listed | 286.007.364 | 050.017.354 | by seat code |
| M Santoprene/PTFE | 476-042-644 | 286.007.354 | 050.018.600 | PTFE seals (by seat code) |
| N Neoprene/Neoprene | 476-042-365 | 286.007.365 | 050.017.365 | 722.040.365 |
| Z One-Piece Bonded/PTFE | 476-042-659 | 286.118.000 | 050.018.600 | 722.040.600 |
| Air End Kit · aluminium centre | 476-421-000 | – | – | – |
| Air End Kit · cast iron centre | 476-421-010 | – | – | – |
| Air End Kit · stainless centre | 476-421-110 | – | – | – |
| Air End Kit · stroke indicator, aluminium centre | 476-170-558 | – | – | – |
Kit numbers (dashed) and part numbers (dotted) as printed in the Sandpiper S20 Metallic service manual, Design Level 1 (s20mdl1sm-rev0625). Weighted Nitrile, EPDM and Neoprene balls carry a W suffix (e.g. 050.017.360W). One-piece bonded conversion uses kit 475-253-000 (diaphragms 286-118-000 with inner plates 612-214-150). Manual figures: 2" NPT or BSPT internal ports or 2" ANSI 150# raised-face flange, 0–758 L/min (200 US gpm), heads to 86 m, 8.6 bar (125 psi) maximum operating pressure, solids to 6 mm, 1.7 L per stroke, 3/4" NPT air inlet, 1" NPT exhaust; shipping weight 31 kg aluminium, 59 kg cast iron, 52 kg stainless steel.
Troubleshooting
Pump cycles once then stops
Likely cause: system pressure at or above the air supply pressure (deadhead), air valve or intermediate gaskets fitted out of line, or a bent or missing actuator plunger. Action: raise the inlet air pressure, refit the gaskets (items 19–22) with holes aligned, and pull the pilot valve to inspect the actuator plungers (item 33).
Pump will not cycle at all
Likely cause: too much line lubrication, not enough air volume or pressure, a blocked or iced muffler, or a closed or clogged discharge. Action: turn the lubricator down or remove it, check the air line and compressor, clean or de-ice the muffler, then inspect the air valve and pilot valve.
Pump cycles but will not prime or deliver
Likely cause: cavitation, balls sticking or missing, worn or chemically attacked balls and seats, a blocked suction line or air leaking in on the suction side. Action: move the pump closer to the product, clear the suction, check the seat O-rings and gaskets, and renew the balls (item 2) and seats (item 37) if worn.
Flow sluggish or pump stalling
Likely cause: icing in the exhaust, an undersized air or suction line, air volume too high for the system so the pump cavitates, or air trapped in the chambers. Action: fit a point-of-use air dryer, enlarge the air and suction lines to at least port size, and reduce the inlet air to suit the duty.
Product coming out of the exhaust
Likely cause: a ruptured diaphragm, loose diaphragm plates, or a diaphragm stretched at the centre or bolt holes from excess pressure or an incompatible product. Action: fit new diaphragms (item 16), tighten the plates to the torque on the exploded view, and check the material against the duty.
Diaphragms keep failing early
Likely cause: cavitation, high flooded-suction pressure, a chemical mismatch, or diaphragm plates fitted backwards or worn to a sharp edge. Action: enlarge the suction pipe, lower the inlet pressure or add a back-pressure device, and replace worn plates (items 28–32).
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