We have successfully completed the machining and non-destructive testing (NDT) of a batch of custom integrally forged hillside nozzles (lateral nozzles) designed for high-pressure vessels. These heavy-wall, self-reinforced nozzles are manufactured from premium forgings and designed in strict accordance with ASME Section VIII pressure vessel codes. By utilizing an integrally reinforced design, these nozzles rely on their own increased wall thickness to compensate for the strength reduction caused by the vessel opening, eliminating the need for conventional reinforcing pads and significantly improving fatigue resistance under high-pressure, high-temperature, and cyclic loading conditions.
The primary manufacturing challenge of these hillside nozzles lies in their off-center, non-radial alignment with the vessel shell, which creates an asymmetrical 3D saddle intersection curve. To resolve this geometric complexity, our engineering team utilized advanced 3D digital modeling to program multi-axis CNC machining centers. This allowed for the high-precision milling of the complex saddle weld bevels and internal transition zones, maintaining bevel angles and root faces within tight design tolerances. This high-precision machining ensures a uniform fit-up gap during subsequent welding to the vessel cylinder, minimizing manual grinding and significantly reducing the risk of welding distortion.
To guarantee the structural integrity and long-term reliability of these critical pressure-retaining components, a comprehensive quality control protocol was executed. Our quality assurance team conducted 100% Ultrasonic Testing (UT) on the raw forgings to ensure they were free of internal volumetric defects such as slag inclusions or internal cracks. Following the machining process, a 100% Liquid Penetrant Testing (PT) was performed on all weld prep surfaces and transition radii to confirm zero surface cracks or micro-defects. After passing final dimensional inspections and receiving rust-preventative surface treatments, the completed nozzles were secured in customized wooden crates and dispatched to the customer's fabrication site for shell integration and assembly.
