Product: 90-degree marine deck / cockpit drain, with a three-hole mounting version shown in the project photos
Material: CF8M cast stainless steel specified to ASTM A351
Route: Silica-sol investment casting, solution treatment and passivation
Application: Drainage from a vessel deck or cockpit into a connected hose
Marine deck drain requirements
The drain combines a perforated top grate, mounting flange, 90-degree outlet and barbed hose tail. For this anonymized marine-parts project, the customer wanted open grate holes, a controlled flange and hose connection, and a finish suited to the specified chloride-exposed service. The three photographs show different versions from the same project, not a before-and-after finishing sequence. The illustrated version has three mounting holes.
Investment casting and finishing response
The small grate openings and curved outlet created cleaning and casting-soundness risks. The team revised wax tooling around the openings, used solidification review to adjust feeding near the elbow, and cleared residual burrs from the grate after shell removal. The project route included solution treatment, glass-bead finishing and passivation, with limited finish machining at the flange. These operations were defined for this project under the investment casting route.
Verification and result
Verification included heat-level material analysis, first-article dimensional inspection, penetrant checks of production parts and radiographic review of the first-article elbow region. The assembled drain and hose connection were checked at the project’s specified 0.3 MPa water pressure for five minutes. Customer-specified neutral salt-spray samples showed no red rust after 500 hours. These results describe the tested project configuration; they do not predict service life in every seawater environment. The approved versions moved from sample confirmation into batch supply with traceable inspection records. See how project inspection scope is tied to the drawing and acceptance plan.
