Carbon Steel Heat Exchanger Tube Bundle with ASME SA179 Tubes and SA266 Gr.2 Tubesheet for Drop-in Replacement

Yuhong Group Co., Ltd. manufactures high‑integrity tube bundles as well as complete shell & tube heat exchangers, pressure vessels, and air coolers. Our replacement bundles are built to match your existing equipment - same tube count, diameter, length, and baffle pattern - ensuring a seamless fit with zero field modification. Every bundle is fabricated under ASME code using certified carbon steel materials.

The carbon steel tube bundle is the removable core of a shell & tube heat exchanger. It consists of ASME SA179 seamless tubes rolled into an SA266 Gr.2 forged tubesheet, plus baffles, tie rods, and spacers. This bundle is designed for non‑corrosive or mildly corrosive services such as:

• Cooling tower water / closed‑loop cooling water
• Steam condensation (low‑pressure)
• Lube oil, hydraulic oil, transformer oil cooling
• Natural gas or air intercooling / aftercooling
• Process water heating

By replacing an old, fouled, or leaking bundle, you restore original thermal duty and avoid the cost of a new exchanger shell.

• Tube‑to‑tubesheet joint: Hydraulic expansion + light seal weld (optional). Each joint is tested by hydrostatic pressure on the shell side.
• Impingement protection: For high‑velocity inlet nozzles, a replaceable stainless steel impingement plate is bolted to the tubesheet face to protect tube ends from erosion.
• Vibration control: Baffle spacing is calculated based on shell‑side flow velocity and tube natural frequency - reduces fretting and fatigue failure.
• Corrosion allowance: Tubes supplied with standard wall thickness (BWG 14‑18) plus optional extra thickness for longer life in slightly aggressive water.

To ensure a perfect fit, we need the following information (you can provide any of these):

1. Original drawing - Best option. We follow tube layout, baffle cut orientation, and tie rod positions exactly.
2. Old bundle dimensions - Overall length, shell ID, tube OD & wall thickness, tube pitch, number of tubes, baffle spacing & thickness.
3. Exchanger model / TEMA type - AES, BEM, etc. Helps us infer standard dimensions.
4. Service conditions - Fluids, temperatures, pressures - so we can suggest material upgrades if needed.

• Incorrect tube count - Using old bundle tube count might ignore plugged tubes. We rely on shell ID and pitch calculation.
• Wrong baffle orientation - Baffle cut direction (horizontal vs. vertical) affects drainage and flow distribution. We check against exchanger orientation.
• Tubesheet thickness mismatch - A thicker tubesheet may clash with gasket seating. We match original thickness.
• No impingement plate - Without it, tube ends can erode in months. We include impingement protection by default for liquid inlet nozzles >3 m/s.

• Your existing shell is in good condition (no severe shell corrosion or gasket leak history).
• Water chemistry is controlled (pH 7‑9, chlorides <200 ppm, oxygen scavenged).
• You need a fast, economical fix - bundle replacement cost is typically 30‑50% of a complete new exchanger.
• You plan to upgrade later - a new carbon steel bundle buys 10‑15 years of service while you budget for a full stainless steel exchanger.

• Refineries - Crude preheat, gas oil cooling, overhead condensers.
• Power plants - Generator air coolers, transformer oil coolers, closed cooling water.
• HVAC district heating - Steam converters, hot water generators.
• Compression stations - Gas intercoolers and aftercoolers.
• Marine (freshwater circuits) - Central coolers, engine jacket water coolers.

Every carbon steel tube bundle shipped from Yuhong Group includes:

• Mill Test Certificates (MTC) for tubes, tubesheet plate, and baffle plates.
• Hydrostatic test report - shell side and tube side.
• Dimensional inspection report - verifying fit with your shell.
• Weld procedure & welder qualifications (if seal welding applied).
• Optional third‑party inspection (SGS, BV, TV) at buyer's request.