Desalination plants run the most chloride-loaded pump and valve applications in existence, and their operators buy spares on plant availability, not on catalogue cycles. We machine high-pressure pump parts, membrane-end components and dosing-system fittings in Super Duplex and Monel 400 from 200 pieces, quoted in 48 hours with 3.1 certificates. Framework agreements and operator call-offs run on the same certified process.
| High-pressure pump parts | Super Duplex, turned + ground |
| Membrane-end components | Duplex, 316L, turned |
| Dosing-system fittings | Monel 400, 316L, sliding-head turned |
| Batch range | 200–20,000 pcs |
| Tolerance scheme | ±0.005 mm, Ra ≤ 0.8 µm seals |
| Documents | EN 10204 3.1, dimensional report |
Every component inside a seawater reverse-osmosis train fights chloride: high-pressure pump shafts, membrane-end hardware, dosing lines. Operators standardize on duplex, Super Duplex and Monel 400 precisely because ordinary stainless fails there — which means the spares market selects suppliers by alloy capability first and price second. A machine shop that treats Super Duplex as an exotic loses the bid before pricing. Operators standardize their spares files around alloy certificates and fit reports, which means the supplier who documents better, not just cheaper, stays on the approved list through every maintenance window.
Super Duplex, duplex, Monel 400 and 316L are running materials on our lines, with per-alloy tooling engineered to protect finish on the corrosion-resistant phases. High-pressure pump parts are turned and ground with fits reported on both mating certificates; dosing-system fittings run on sliding-head lathes from 200 pieces. First articles take 7–15 days, DDP spares arrive in 5–8 days by air, and repeat orders reissue against your part number with identical documentation. Matched shaft and wear-ring sets ship with the fit dimension reported on both mating certificates, and operator-side spares run on the same process and documentation as OEM project quantities.
| Component (IT / EN) | Typical material | Process | Typical batch |
|---|---|---|---|
| HP pump shafts | Super Duplex | Turning + grinding | 200–2,000 |
| Membrane-end components | Duplex / 316L | Turning | 500–10,000 |
| Dosing fittings | Monel 400 / 316L | Sliding-head turning | 1,000–20,000 |
| Wear rings & bushes | Super Duplex | Turning | 500–10,000 |
Operator-side spares and OEM project quantities run on the same certified process, documentation and traceability format.
The standard flow: drawing review and quotation within 48 hours, first samples in 7–15 days, first article inspection and approval, then series production against the approved reference. Tooling, program revisions and inspection records are kept on file so that call-offs remain consistent with the approved first article.
Engineering changes — material substitutions, tolerance updates, plating or packaging changes — are handled as controlled changes against the same records.
DIN ISO 2768-mK applies as the default tolerance scheme for unspecified dimensions. EN 10204 3.1 inspection certificates are standard for metallic parts, First Article Inspection supports the approval step, and RoHS/REACH declarations are available where required. Plating, cleanliness and packaging requirements are confirmed per drawing.
Which alloys do you recommend for seawater service?
For high-pressure pump internals we run Super Duplex as the default, with Monel 400 where dosing chemicals dominate, and duplex or 316L for less aggressive positions. The choice is yours; what we add is per-alloy tooling that keeps the corrosion-resistant phases intact during machining, plus 3.1 certificates showing the actual melt analysis against the specified grade.
Can you match spares to running plants without drawings?
Yes. Worn parts arrive as samples and leave as reverse-engineered first articles with a full dimensional report in 7 to 15 days. Operators use this route when the original OEM quote or lead time no longer fits a maintenance window; the dimensional report also flags any wear-related deviations so the fit is decided before installation, not after.
How do you handle operator-side framework agreements?
Running part numbers are stored with process specification, certificates and inspection plan, so call-offs need only a quantity and date. Standard spares deliver DDP in 5 to 8 days by air; framework pricing is tiered by annual volume, and the documentation set repeats identically on every delivery so plant quality files stay uniform across years.
What are the payment and delivery terms?
New relationships start with 30 percent on order and 70 percent before shipment, or an irrevocable letter of credit for framework values. Standard spares deliver DDP in 5 to 8 days by air including customs clearance, or 35 to 45 days by sea for planned call-offs, and split shipments put any single critical dimension on the first flight when a maintenance window is tight.
Send your drawing — Sinbo Precision will review material, tolerance scheme and batch plan and return a quotation within 48 hours. Samples in 7–15 days.
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