Specialty forgers can manufacture custom, high-quality, seamless rolled rings in a variety of materials and finishes in as little as eight weeks.
In the shipbuilding industry, high-quality forgings such as long shafts, step shafts, propeller components and other shaped parts are essential for the construction of cruise liners, super tankers, LNG carriers, drill ships and other vessels.
These precision-forged parts are often found in applications where it is critical to withstand challenging conditions. Open-die forgings and seamless rolled rings have a greater lifespan than other products due to their strength and durability, and are less prone to cracking or warping, making the option ideal for critical components requiring high-tensile strength.
Depending on the metal and alloy, the rings are also resistant to thermal and chemical damage, which further extends longevity while reducing the need for maintenance, repair and replacement.
Seamless rolled rings can be used in the manufacture of propeller shafts to ensure steadfast strength and reliability amidst the rigors of the marine environment; in steering systems in ships to furnish precision and durability essential for effective navigation and maneuverability, and in anchor systems to secure steadfast anchorage across diverse marine conditions in order to safeguard vessels against shifting tides and currents.
With robust, durable, high-performance construction, seamless rolled rings are vital to marine engineering and shipbuilding endeavors, fortifying vessels to traverse the world’s oceans with unparalleled resilience and reliability.
Yet for shipbuilders, obtaining large heads and seamless rolled rings in a timely manner remains a significant challenge. Currently, it may take many months to receive forged components after placing an order. This delay can have a severe impact on the production and maintenance schedules of firms that depend on replacement parts.
Rings are typically provided with a rough surface finish, which necessitates the use of CNC machining to achieve the required level of smoothness. This poses a challenge for machine shops with a high workload, as allocating machine time for finishing inevitably leads to a decrease in production speed and an increase in costs, ultimately impacting the end-use cost or profitability.
Fortunately, shipbuilders can rely on industry-leading forging specialists capable of producing large, custom, seamless rolled rings, and contoured seamless rolled rings with the required surface finish, in under two months.
One example, All Metals & Forge Group, a manufacturer of custom and standard open-die forged parts and seamless rolled rings, can deliver the components with the required finish within 10 weeks.
The range of forged products includes rings, discs, hubs, blocks, shafts—including step shafts or those with flanges—sleeves, gear blanks, cylinders, flats, hexes, rounds, plates and custom shapes. Carbon steel, alloy steel, stainless steel, nickel, titanium and aluminum are among the materials used for forging.
The forgings meet industry specifications such as ASTM, AMS, AISI, ASME, Boeing, SAE, GE, DIN, ASME B 16.5, ASME B16.47 and API 6A.
When speed and quality are essential, the shipbuilding industry can reap the advantages of an accelerated process for obtaining flawless rolled rings.
The Benefits of Open Die Forgings
One of the chief advantages of open-die forging is the customization it offers in the forged parts and seamless rolled ring manufacturing process.
Open-die forging is ideal for providing large, custom parts. As an example, All Metals & Forge Group can produce seamless rolled rings or contoured rolled rings up to 200 inches in outside diameter and custom forgings up to 40 feet long or 80,000 lbs.
The company, which has been manufacturing and selling open-die forgings and seamless rolled rings for more than 50 years, also can produce forgings for drive and tending ends and large cylinders in diameters that cover the sizes needed in the food-processing industry.
While open-die forging is typically associated with larger, simply shaped parts like bars or blanks, the process enables the creation of “custom-designed” metal components.
Open-die forging facilitates the production of seamless rolled rings to exact specifications with optimized mechanical properties and structural integrity. The rings can be produced in a variety of alloys, sizes and shapes specific to the requirements.
Forged parts finished by machine shops are equally sound in structural integrity and required physical properties.
The forging of seamless or contoured rolled rings is also cost effective since the process reduces material waste and manufacturing costs. Since the rings are constructed from a single metal piece using a specialized ring-rolling machine, there is no need for welding or assembly, saving time and labor.
The seamless rolled rings also are more structurally sound because they create a circular grain flow in the material following the shape of the ring, which increases strength and integrity, creating a refined grain structure.
This can enhance the material’s fatigue resistance and overall performance, resulting in a stronger, more durable final product compared to other methods of ring making, such as cutting from plate or rolled and welded.
Near Net Shape Parts with Finer Surface Finish
Typically, when heads, cylinders, shafts or seamless rolled rings are forged, they’re often left in an unprocessed state with a rough surface measured at about 500 root mean square (RMS). As a result, significant CNC (computer numerical control) machining time is required to achieve a smoother surface for the finished machined part.
This poses a challenge for machine shops as the allocation of machining time for finishing these rough parts directly affects production efficiency, cost and delivery time to the client.
To optimize efficiency and reduce costs, All Metals & Forge Group frequently provides near-net-shaped forged parts with more refined surface finishes. Typically, the company provides a 250 RMS surface finish. However, it can provide 125 RMS, drill holes and even do contour forgings as needed.
Some forge shops only offer a raw unmachined part. In contrast, AMFG produces a rough machine part, saving machine shop time and equipment wear and tear, since they have already taken the first rough cuts off the ring or forged parts.
In addition, the company has said that it conducts ultrasonic testing at zero expense to the customer to guarantee the absence of internal cracks, pits or voids.
Streamlining Delivery
In today’s market, the procurement of forged seamless rolled rings usually takes a considerable amount of time, from 20 weeks to as much as a year, as there are long lead times in receiving the necessary steel from mills.
To expedite the process for customers, All Metals & Forge Group has established strategic partnerships within the industry, enabling the company to deliver many custom forgings in eight-to-10 weeks.
Furthermore, to minimize any potential production downtime for machine shops, the company strives to provide quotes within 48 hours.
Positioning for the Future
The need to acquire seamless rolled rings only will increase in industries like shipbuilding that require high-quality custom-forged components that can safely withstand extreme forces with minimal repair or replacement. In these cases, working with an expert forger who can expedite the process can convey a significant advantage.
Del Williams is a technical writer based in Torrance, Calif.