7 Sets of Atlas Copco ZH560 Intercooler & Aftercooler Bundles Heading to India — QC, Pressure Test and Seal Test Completed
Seven intercooler + aftercooler pairs for Atlas Copco ZH560 centrifugal compressors left Turbomax Suzhou this week, bound for a refinery customer in India. Every bundle in the batch cleared three stages of final verification — dimensional inspection against Atlas Copco OEM drawings, hydrostatic pressure test at 1.5× design pressure, and pneumatic seal test holding full design pressure for 30 minutes — before packing.
One batch of Atlas Copco ZH560 cooler bundles bound for India
An Indian refinery customer placed an order for a complete batch of replacement intercooler and aftercooler bundles for their Atlas Copco ZH560 centrifugal compressors — a matched set, one intercooler and one aftercooler per compressor. The ZH560 is a 560 kW class integrally geared centrifugal compressor commonly used in refinery air, petrochemical process gas and instrument air packages. Every bundle is designed to drop into the original shell without any modification to the compressor frame, piping or mounting base.
Turbomax has been building replacement cooler bundles for Atlas Copco centrifugal compressors since 2017. This batch was manufactured as a single production run sharing the same tube-sheet tooling and tube-count geometry, which let us run a unified QC and test programme across the whole lot — every unit cleared verification within two days of finishing assembly.
Step 1 — Dimensional inspection against OEM drawings
The first QC gate is dimensional verification. A compressor intercooler bundle has dozens of critical dimensions that must match the OEM drawing within tight tolerances, because the bundle slides into a fixed shell and mates with pre-drilled nozzles. If the tube sheet is even 1–2 mm too large, or the nozzle spacing is off, the bundle will not fit on site.
For this ZH560 batch we recorded 14 dimensions per bundle, including:
- Tube sheet outer diameter (tolerance −0 / +1 mm)
- Overall bundle length (intercooler & aftercooler each recorded separately)
- Nozzle flange centre-to-centre spacing
- Tube pitch and tube sheet flatness
- Cooling fin height and density
- Mounting foot hole positions
Every bundle in this batch passed on the first check. No rework was needed — a good sign that our CNC tube-sheet cutter and jig-fixture setup for the ZH platform is now dialed in after five previous Atlas Copco cooler orders.
Step 2 — Hydrostatic pressure test (1.5× design pressure)
Dimensional pass clears the way for the pressure test — the most important single check for any pressure vessel. Every intercooler and aftercooler in this batch was pressurised with water to 1.5× its design pressure, held for 20 minutes, then visually inspected for leakage and watched for any pressure gauge drop.
The Atlas Copco ZH560 intercooler operates at approximately 5.5 bar air side / 4 bar water side, and the aftercooler at approximately 8.5 bar air side / 4 bar water side. Test pressures were 8.25 bar and 12.75 bar respectively on the air side. Both sides of each bundle are tested — air side first, then water side — because a tube failure leaks between the two circuits and would not show up if only one side was pressurised.
Hydrostatic testing catches the three most common manufacturing defects in cooler bundles:
- Thin tube walls from an under-spec raw tube batch
- Poor brazing between the tube and the tube sheet
- Cracks or porosity in the tube sheet itself
Every bundle held pressure stably for 20 minutes with zero pressure drop. No weeping, no seepage, no tube rupture.
Step 3 — Pneumatic seal test at full design pressure
After the hydrostatic test, we run a pneumatic seal test at 1.0× design pressure, holding for 30 minutes. This is a leak-detection test, not a burst test — air under pressure is far more sensitive than water at finding tiny weep paths that would show up as air loss during compressor operation but might not leak water at all.
We fill the air side with compressed dry air up to the bundle's rated working pressure, valve it off, and monitor the precision pressure gauge. A pressure drop greater than 0.1 bar in 30 minutes fails the unit. Every bundle in this ZH560 batch held within that tolerance — in most cases the needle did not move at all.
Turbomax builds intercooler & aftercooler bundles for four centrifugal-compressor brands
The Atlas Copco ZH560 batch going to India is one example of what we do every month. Turbomax manufactures and ships replacement intercooler-aftercooler bundles for four major centrifugal compressor platforms, all built to the OEM drawing and pressure-tested before export:
| Brand | Model families we support | Typical bundle |
|---|---|---|
| Atlas Copco | ZH315, ZH450, ZH560, ZH750, ZH900 and other Z-series centrifugal compressors | Turbomax ZH560 intercooler & aftercooler bundle (this article) |
| Hanwha | TM and SM series multi-stage centrifugal compressors | Turbomax reverse-engineers Hanwha cooler bundles from OEM drawings |
| FS-Elliott | P300, P400, P500, P600, P700 and WR series oil-free centrifugal compressors | Built to OEM drawing; cupronickel tubes available for seawater-cooled units |
| Cameron / Ingersoll Rand | TA2000, TA3000, TA6000, TA9000, TA11000, MSG series integrally geared centrifugal compressors | Copper-tube bundles — see our Cameron TA6000 overhaul case and tube material guide |
Every bundle we ship, regardless of brand, is accompanied by a material certificate for the tube and tube sheet, a hydrostatic test report, and a pneumatic seal test report with the test pressure, hold time and pressure-drop reading. These documents are what major industrial operators need to close the loop with their own QA departments before installing the unit on site.
Frequently asked questions
What tests did the Atlas Copco ZH560 bundles pass?
Three stages: (1) dimensional inspection against Atlas Copco OEM drawing tolerances on 14 critical dimensions per bundle; (2) hydrostatic pressure test at 1.5× design pressure, both air and water sides, held 20 minutes; (3) pneumatic seal test at 1.0× design pressure held 30 minutes with pressure drop under 0.1 bar.
Why is a compressor cooler pressure test important?
Centrifugal compressor coolers operate at 4–12 bar across a temperature swing of 40–120 °C. A poorly brazed tube joint or a thin tube wall that passes visual inspection can fail catastrophically in service — a tube rupture dumps water into the air circuit, contaminates the oil system, and can destroy the compressor within minutes. Hydrostatic testing is the industry-standard defence against that risk.
Which Atlas Copco Z-series compressors share the same cooler platform?
The ZH315, ZH450, ZH560, ZH750 and ZH900 all belong to the same Z-series family and share a common tube-sheet architecture. Bundle length, tube count and tube sheet diameter vary by model, but the nozzle flange standard and material specification are closely related. Send us your OEM drawing number or a photo of the nameplate and we can quote.
Do you ship to India?
Yes — this batch literally goes to India this week. We ship worldwide by sea freight, air freight and truck-in-CN; Indian destinations typically clear Chennai, Mundra or Nhava Sheva ports with a standard 3–5 day customs clearance for pressure vessels with test reports.
How long does a replacement bundle take to manufacture?
For a brand we have already tooled — Atlas Copco Z-series, Hanwha TM/SM, FS-Elliott P300-P700/WR, Cameron TA/MSG — lead time is typically 4–6 weeks. For a new bundle where we first reverse-engineer the OEM drawing, add 1–2 weeks for tooling.
Need a replacement cooler bundle for a centrifugal compressor?
Whether you have an Atlas Copco ZH, a Hanwha TM/SM, an FS-Elliott P300-P700 or a Cameron TA centrifugal compressor, Turbomax (Suzhou, China) can build a replacement intercooler and aftercooler bundle to OEM specification, test it hydrostatically and pneumatically, and ship it worldwide.