Stainless Steel Tank Manways by MTS Forge

A manway on a tank is a closable opening—typically circular or oval—built into the wall or top of a pressure vessel, storage tank, or industrial vessel. It provides physical access for personnel to enter the tank for inspection, cleaning, maintenance, or repair. Manways are forged or fabricated components designed to withstand the same pressure and temperature conditions as the surrounding vessel structure.

The primary purpose of a manway is to provide safe, reliable access to the interior of a closed tank or pressure vessel without compromising structural integrity. Manways allow operators and maintenance crews to inspect internal surfaces, remove deposits or sediment, install or service internal components, and perform required regulatory inspections—all while maintaining a pressure-rated, leak-proof seal when closed.

MTS Forge produces manways in a range of stainless steel grades, including 316-L stainless steel for corrosion-critical and nuclear Section III applications, as well as duplex stainless steels like Ferralium 255 for environments demanding higher strength and pitting resistance. Material selection depends on operating pressure, temperature, media compatibility, and applicable industry standards.

Forged stainless steel manways are used across chemical processing, petroleum and gas, commercial nuclear power, power generation, aerospace, defense, and food-grade manufacturing. Any industry operating closed pressure vessels, storage tanks, or process vessels that require periodic internal access relies on properly rated manway assemblies to meet safety and regulatory requirements.

Every manway produced at MTS Forge is manufactured under a comprehensive Quality Assurance Program that includes full material traceability from raw stock through finished forging. Our QA framework covers Mil I 45208, NCA 3800, and Mil Q9858 certifications, ensuring each component can be tracked, tested, and documented to meet the stringent procurement requirements of defense, nuclear, and industrial customers.

Yes. MTS Forge routinely manufactures manways to customer-supplied drawings and specifications. Our in-house tooling design and development capability allows us to produce custom geometries cost-effectively, without requiring customers to source external tooling vendors. We work with procurement teams and engineers from initial specification review through finished component delivery, ensuring dimensional conformance at every stage.

Yes. MTS Forge provides in-house rough machining for forged manway components immediately following the forging process. This brings parts to near-net shape—removing forging flash, surface irregularities, and dimensional excess—so customers receive components ready for final machining, inspection, or direct application. This single-source capability reduces lead times and eliminates the coordination burden of a separate machining vendor.

MTS Forge performs normalizing heat treatment on forged manway components at its Coatesville, PA facility. Normalizing heats the forging above its upper critical temperature and then cools it in still air, breaking up uneven grain structures created during forging. The result is a uniform microstructure with improved tensile strength, enhanced toughness, relieved internal stresses, and better machinability—critical properties for manways in high-pressure service.