API 661 Air Cooled Heat Exchanger, ASME U Stamp certificated for Oil Refinery

API 661 Air Cooled Heat Exchanger, ASME U Stamp certificated for Oil Refinery

Product Description
This ASME U Stamp certified API 661 plug type air cooled heat exchanger is designed for high-pressure oil refinery processes. Featuring carbon steel or stainless steel finned tubes, the plug header configuration ensures absolute sealing integrity under pressures up to 15-30 MPa. Engineered for heavy-fouling hydroprocessing, refining fractions, and extreme thermal conditions, this low-maintenance air cooler provides optimal heat dissipation and complete water conservation.

Product Specifications

Introduction

Core Standard: Fabricated in strict accordance with API 661 (Air-Cooled Heat Exchangers for General Refinery Service) and ASME Section VIII Division 1 codes.

Header Geometry: Constructed from solid forgings or heavy welded plates. Threaded plug holes are machined into the header sheet directly opposite each tube end.

Sealing Mechanism: Individual tube access and pressure sealing are achieved via high-precision threaded plugs combined with metallic gaskets.

Compliance: Fully certified with the ASME "U" Stamp and registered with the National Board (NB), specifically engineered for high-pressure, hazardous refinery environments.

Key Advantages

High-Pressure Sealing Integrity: Eliminates the risk of flange warping or gasket blowout under extreme thermal cycles. The solid plug header configuration easily withstands severe hydrostatic testing from 15 MPa to 30 MPa.

Single-Tube Maintenance: Enables isolated inspection, mechanical cleaning, or tube plugging. Operators can service specific tubes by removing individual plugs, preventing the need to dismantle the entire header.

Precision Fabrication: * Materials (MOC): Base tubes utilize SA106B carbon steel or SA213-TP316L stainless steel, mechanically bonded with helical aluminum high-fins.

Robotic Joining: Advanced Yuhong automated welding robots execute combined strength-expanding and seal-welding to guarantee zero-leakage joints.

Stress Relief: Mandatory Post-Weld Heat Treatment (PWHT) is performed on the fully welded headers to eliminate residual stresses and prevent Stress Corrosion Cracking (SCC).

Typical Applications

High-Pressure Refinery Processes: Ideal for hydrodesulfurization (HDS), hydrocracking, and catalytic reforming reactor effluent cooling.

Hazardous Fluid Condensing: Applied in crude distillation unit (CDU) overhead gas condensing where zero tolerance for hazardous atmospheric leakage is required.

Arid Regions: Offers 100% water conservation, eliminating the scaling, chemical water treatment overheads, and wastewater discharge liabilities associated with water-cooled systems.

Comparison: Plug Type vs. Removable Cover Plate Type

Pressure Thresholds:

-Plug Type: The inherently rigid, bolt-free box structure safely handles severe high-pressure applications exceeding 10 MPa (up to 35 MPa).

-Removable Cover Plate Type: Limited by the potential deflection of large rectangular cover plates and long perimeter bolting. It is generally restricted to low-to-medium pressure processes below 5–7 MPa.

Cleaning & Inspection Efficiency:

-Plug Type: Requires individual plug removal for tube cleaning. For high-fouling, heavy residual crude streams, total turnaround cleaning takes longer.

-Removable Cover Plate Type: Removing the perimeter bolts exposes the entire tube sheet instantly. This allows rapid mechanical brushing and chemical flushing, making it highly effective for low-pressure, high-fouling applications.

Maintenance & Joint Reliability:

-Plug Type: Relies on localized, small-diameter plug gaskets. The reduced sealing perimeter minimizes maintenance overheads and delivers high operational consistency during sudden thermal shocks.

-Removable Cover Plate Type: Utilizes a large, single perimeter gasket. High temperature differentials cause uneven thermal expansion across the plate, increasing the risk of gasket failure and requiring frequent torque checks.

Yuhong Holding Group Co., Ltd. is a premier global manufacturer specializing in high-end process equipment, including heavy-duty shell and tube heat exchangers, air coolers, condensers, evaporators, and custom pressure vessels. Strategically positioned to serve the mid-to-high-end industrial sectors, Yuhong delivers robust thermal and mechanical solutions engineered for extreme operating environments across oil refining, petrochemical, chemical processing, and power generation industries.