U-tube Tube Bundles for Refinery Combined Feed Heaters

A U-tube tube bundle consists of tubes bent into a U-shape and attached to a single tubesheet. This design allows both ends of each tube to be mounted in one tubesheet, enabling efficient handling of thermal expansion and simplifying maintenance.

In refinery combined feed heaters, these tube bundles transfer heat from hot process streams, hot oil, or exhaust gases to mixed feed streams consisting of gasoil, naphtha, recycle oil, hydrogen-rich gases, or other hydrocarbons.

Why U-Tube Bundles Are Ideal for Refinery Combined Feed Heaters

Refinery combined feed heaters operate in extreme thermal and mechanical conditions, including high temperatures, large temperature differentials (ΔT), variable flow rates, and fouling-prone hydrocarbon streams. U-tube bundles offer several advantages:

1. Handles High Thermal Expansion

The U-bend naturally absorbs differential thermal expansion between the tube side and shell side—especially important in CFHs where inlet temperatures can exceed 300–400 °C.

2. Robust Performance Under Variable Loads

Thermal shocks, transients, startup/shutdown cycles, and fluctuating feed compositions are common in refinery heaters. U-tube bundles endure these conditions without mechanical failure.

3. Easier Maintenance and Replacement

With only one tubesheet:

• The bundle can be pulled for cleaning

• Fewer sealing surfaces reduce failure points

• Lower overall maintenance complexity

4. Cost-Effective Construction

Compared to floating-head or TEMA S/K designs, U-tube bundles offer a lower-cost, simpler manufacturing process while delivering high performance.

Refinery Applications

U-tube tube bundles are widely used in:

• Hydrotreating Units (HDT / HDS) Combined Feed Heaters

• Hydrocracking Units (HCU) Feed/Product Exchangers

• FCC Preheat Train Exchangers

• CDU/VDU Heater Preheat Exchangers

• Hot Oil to Feed Heat Exchangers

Their reliability makes them indispensable in refinery heat-integration networks.

Custom Engineering & Manufacturing Capabilities

We design and manufacture OEM-quality U-tube tube bundles that meet or exceed ASME and TEMA standards, including:

• Reverse-engineering of existing refinery heaters

• Fabricating replacement bundles for legacy units

• Custom metallurgy options

• Bundle performance optimization

• Hydrostatic testing, NDT, PMI, and quality inspection

Whether for a small preheat exchanger or a large refinery feed heater, our U-tube bundles deliver long-term, high-performance reliability.