Custom Slewing Bearing Ring Manufacturer
Slewing Bearing Ring
Frequently Asked Questions About Custom Slewing Bearing Rings
1. What slewing bearing ring components does SIMIS manufacture?
SIMIS manufactures custom slewing bearing inner rings, outer rings, gear rings and annular bearing blanks according to OEM drawings. Products may have external gear teeth, internal gear teeth or no gearing. The main manufacturing route is seamless rolled ring forging for suitable carbon and alloy steels, supported by open-die forging and approved casting methods for selected components. Customers can purchase forged or cast ring blanks and specified finished metal rings within the agreed order scope.
2. Can SIMIS supply seamless ring-rolled steel bearing races?
Yes. SIMIS offers seamless ring rolling for compatible large-diameter steel rings. A heated annular preform is expanded and shaped between rollers to achieve the specified general diameter and cross-section. Suitable materials may include 42CrMo4, AISI 4140, C45, S48C and customer-approved forging grades. Ring rolling forms the blank; finished raceway grooves, mounting faces, holes and gear teeth are completed as separately specified operations.
3. Are cast steel or ductile iron slewing rings available?
SIMIS can manufacture suitable cast steel or ductile iron annular components through sand casting and other approved foundry processes. Cast rings may be appropriate for selected industrial rotating structures or bearing-related parts where the OEM approves their material and duty. Ductile iron is not a universal substitute for forged alloy steel in heavily loaded bearing raceways. The bearing design, rolling contact requirements and material grade determine whether a casting is appropriate.
4. What materials are commonly used for custom slewing bearing rings?
Material options include alloy forging steels such as 42CrMo4 and AISI 4140, medium-carbon steels such as C45 and S48C, selected cast steel grades and ductile iron under applicable standards. Stainless steel grades may be specified for suitable corrosion-exposed rings, but common austenitic 304 and 316 are not direct replacements for hardened bearing raceway steel. SIMIS manufactures to the approved material specification rather than assigning one alloy to every ring.
5. What details are needed to quote an OEM slewing bearing ring?
Please send 2D drawings or a 3D CAD model, the required inner or outer ring configuration, material grade, overall ring dimensions and estimated quantity. Important product details include internal, external or no gearing; mounting-hole pattern; raceway geometry; and the intended bearing arrangement. If specified, provide the bearing application and axial, radial and overturning-moment load requirements. SIMIS will quote the agreed forging, casting or finished-component supply scope.
OEM Custom Slewing Bearing Ring Manufacturer in China
Custom slewing bearing rings are annular metal components used in slewing bearings for machinery requiring relative rotation between large structural members. A typical complete slewing bearing contains an inner ring and outer ring, rolling elements and, depending on the design, cages, seals or other parts. The rings provide mounting interfaces and raceway surfaces for the rolling contact arrangement.
SIMIS manufactures OEM slewing bearing inner and outer rings, seamless ring-rolled alloy steel blanks, internally geared rings, externally geared rings and selected cast annular parts. Our main focus is metal forging and casting to customer drawings, not the design or certification of a complete slewing bearing assembly.
The ring configuration varies by application. Some rings engage with a pinion through integral gear teeth; others are gearless and rely on a separate drive arrangement. Raceway and mounting features differ between ball and roller bearing arrangements. The appropriate material and manufacturing route depend on the drawing and specified duty.
For suitable steel products, SIMIS provides custom seamless ring rolling and open-die forging services. Ring forging is especially relevant to annular blanks before their finished raceway and connection features are produced. Related transmission parts include custom ring gears.
Types of Inner Rings, Outer Rings and Geared Slewing Bearing Components
SIMIS manufactures several ring configurations for OEM slewing equipment. Product names describe the ordered metal component; a fully assembled slewing bearing has additional rolling elements and interfaces that must be defined by its equipment manufacturer.
| Component Type | Typical Metal Features | Manufacturing Considerations |
|---|---|---|
| Slewing Bearing Inner Ring | Annular inner member with the specified mounting holes and raceway location. | Suitable seamless rolled steel blank; selected approved casting designs. |
| Slewing Bearing Outer Ring | Larger-diameter annular member with mating raceway and mounting features. | Ring-rolled carbon or alloy steel; project-approved alternatives. |
| Externally Geared Ring | Gear teeth along the outer circumference for a compatible pinion drive. | Forged ring blank with tooth production according to drawing. |
| Internally Geared Ring | Gear teeth on the internal circumference and customer-defined mounting features. | Rolled or approved cast annular blank, followed by specified finishing. |
| Gearless Slewing Ring | Ring without integral drive teeth, with mounting and raceway interfaces. | Forged or approved cast metal to the selected application. |
| Raceway Ring Blank | Preform supplied before final rolling-contact groove and mounting features. | Open-die forged and seamless ring-rolled blank; finishing scope agreed separately. |
Bearing Rings for Ball and Roller Slewing Arrangements
Depending on the equipment, a complete slewing bearing may use four-point-contact balls, crossed rollers, double-row balls or multiple rows of rollers. These describe different bearing arrangements, not merely different ring materials. SIMIS manufactures ring blanks and compatible finished ring components to the specified raceway arrangement; rolling elements and complete assembly are included only when expressly agreed.
Internal Gear, External Gear and Gearless Rings
An externally geared ring has teeth on the outside diameter; an internally geared ring has teeth on its inner circumference. A gearless ring is manufactured without integral drive teeth. These configurations are selected by the OEM and require compatible mounting, raceway and drive geometry. A rolled ring blank does not emerge from forging with finished precision teeth.
Seamless Ring Rolling, Open-Die Forging and Casting Processes
Seamless ring rolling is the principal forging process for suitable slewing bearing ring blanks. Steel casting and ductile iron casting provide alternatives for selected approved annular parts. The process is selected according to component diameter, section size, material grade, duty and purchasing requirements.
| Manufacturing Process | Suitable Slewing Components | Role in Production |
|---|---|---|
| Seamless Ring Rolling | Forged steel inner rings, outer rings and gear-ring blanks. | Hot rolling expands and forms an annular preform into a seamless ring. |
| Open-Die Forging | Large steel preforms and ring blanks before rolling or finishing. | Upsetting, punching and related hot forging shape suitable steel stock. |
| Steel Sand Casting | Selected large cast annular structures and approved bearing-related parts. | Sand molds form suitable cast steel shapes under customer specifications. |
| Ductile Iron Sand Casting | Specified lower-duty rotating ring components and mounting structures. | Makes compatible cast shapes; not automatically suitable for heavily loaded races. |
| Shell Mold Casting | Selected smaller or repeat-production cast annular components. | Resin-bonded sand shell process for suitable casting geometries. |
| Lost Foam Casting | Approved complex cast ring-related structures. | Expendable foam patterns provide an option for suitable cast components. |
Seamless Rolled Ring Forging for Bearing Ring Blanks
In ring rolling, a steel billet is heated and prepared as an annular preform. Rolling equipment then progressively increases its diameter and forms its wall section. This process is used for compatible carbon steel and alloy steel rings and can provide a seamless blank for later manufacturing operations. Actual mechanical performance depends on the selected steel, forging practice, material condition and finished design.
SIMIS offers steel forging and ring rolling for appropriate OEM parts. Forging establishes the metal preform rather than a universal finished bearing load rating. For very large rings, available dimensions and production feasibility should be confirmed against the specific project.
Open-Die Forging for Large Ring Preforms
Open-die forging can be used before ring rolling to prepare suitable steel preforms. Heated material is compressed and shaped without a fully enclosed impression die. For annular components, upsetting and punching may form the initial ring blank. Open-die methods can also be considered for customer-specific forged rings where the geometry and volume justify the approach.
Sand Casting and Other Approved Casting Options
Sand casting can produce selected cast steel and ductile iron annular components with mounting details that may be difficult to form by simple forging. SIMIS offers sand casting, shell mold casting and lost foam casting for suitable metal parts. Not every process is appropriate for a highly loaded rolling-contact raceway; the selected casting grade and intended bearing duty must be approved by the customer.
Alloy Steel, Carbon Steel, Cast Steel and Ductile Iron Materials
Material selection is specific to the ordered bearing ring. Forged alloy steels are important for suitable structural and rolling-contact rings, while carbon steel and selected cast metals may be appropriate in other applications. Cast and wrought grades use different specifications, and the material choice should follow the OEM drawing.
| Material Grade or Family | Characteristics | Potential Ring Application |
|---|---|---|
| 42CrMo4 / AISI 4140 | Related chromium-molybdenum low-alloy steels; specifications are not automatically identical. | Suitable forged inner and outer ring blanks for specified duties. |
| 50Mn Steel | Medium-carbon manganese steel used in selected mechanical and bearing-ring applications. | Customer-specified forged slewing ring components. |
| C45 / AISI 1045 | Related medium-carbon steels with grade-specific standards. | Selected forged carbon steel rings and annular parts. |
| S48C | Japanese medium-carbon steel designation. | Approved steel slewing ring blanks and structural ring components. |
| AISI 4340 / 34CrNiMo6 | Related nickel-chromium-molybdenum alloy steel families, subject to exact specification. | Special customer-defined forged annular components. |
| Cast Steel | Cast carbon or alloy steels with separately specified casting grades. | Approved cast ring structures and compatible bearing-related parts. |
| ASTM A536 Ductile Iron | Spheroidal graphite iron with grade-dependent mechanical characteristics. | Selected noninterchangeable lower-duty annular structures. |
| 304 / 316 Stainless Steel | Austenitic stainless steels with environment-dependent corrosion resistance. | Suitable corrosion-exposed rings where the raceway design permits. |
42CrMo4, 4140 and 50Mn Forged Steel Rings
Chromium-molybdenum steels such as 42CrMo4 and AISI 4140 are often specified for suitable heavy industrial rings. 50Mn is another material used in selected slewing ring applications. Although some national grades have broadly similar compositions, SIMIS quotes the exact material standard and product condition supplied in the OEM request.
Cast Steel, Ductile Iron and Stainless Steel Options
Cast steel and ductile iron can be considered for compatible applications, particularly where casting provides useful geometry. They are not assumed to have the same rolling-contact or fatigue properties as forged alloy steel. Corrosion-resistant stainless grades are available for selected metal parts; 304 and 316 do not automatically provide the hardened raceway properties required for every bearing. Specific grades and requirements remain subject to customer approval.
Applications in Cranes, Wind Energy, Port Equipment and Industrial Machinery
Slewing bearing rings are used wherever large machinery structures must rotate relative to one another while transferring specified loads. SIMIS supplies OEM ring forgings and compatible cast metal parts for different industrial sectors.
Excavators, Tower Cranes and Rotary Construction Equipment
Excavators, tower cranes and rotary drilling equipment may incorporate slewing bearings between an upper rotating structure and a supporting base. Suitable inner and outer rings require specified mounting and raceway features. SIMIS manufactures forged steel ring blanks and related annular components to the equipment maker's drawings. Finished bearing capacity and equipment safety depend on the complete approved design.
Wind Turbine Yaw and Pitch Systems
Wind turbine yaw and blade-pitch mechanisms may use large bearing arrangements with steel inner and outer rings. The geometry, environmental conditions and required bearing performance vary by turbine. SIMIS supplies suitable ring forgings to drawings for energy and power equipment parts without treating each supplied blank as a certified complete wind turbine bearing.
Port Cranes, Marine Handling and Solar Tracking Equipment
Port cranes and cargo-handling machinery use rotation systems with customer-specific load and mounting requirements. Some solar tracking systems also use slewing drives or ring-related rotating components. For marine service, the relevant corrosion environment and material specification must be established by the OEM rather than inferred solely from stainless steel or a coating designation.
Mining and Heavy Industrial Rotating Platforms
Heavy industrial turntables, certain mining machines and processing equipment can use slewing ring components with internal, external or no gearing. SIMIS supplies compatible forgings and castings for mining machinery and industrial equipment. The exact part configuration depends on the application and drawing.
OEM Slewing Bearing Ring Manufacturing to Customer Drawings
SIMIS specializes in metal forging and casting for custom slewing bearing ring components. Available options include seamless rolled ring forgings, open-die forged preforms, cast steel annular parts and selected ductile iron ring structures. Products are manufactured from customer-specified grades and supplied in the agreed blank, semi-finished or finished condition.
Depending on the purchase order, additional work may include machining of the raceway groove, mounting faces and holes, specified heat treatment, gear tooth production, surface protection and customer-defined inspection. These are finished-part requirements, not separate universal performance claims.
The design of a complete slewing bearing also involves rolling elements, seals, lubrication, assembly and load selection. SIMIS does not assume that an individual ring forging or casting has a particular load capacity, HRC hardness, AGMA or ISO gear accuracy, sub-micron tolerance or certified fatigue life without the corresponding OEM specification and acceptance requirements.
For projects with special operating requirements, the engineering drawings should define the intended bearing arrangement and interfaces. SIMIS then quotes the agreed metal component scope rather than substituting one ring construction for another without customer approval.
Request a Quote for Custom Slewing Bearing Rings
SIMIS welcomes OEM inquiries for forged and cast slewing bearing inner rings, outer rings, geared rings and ring blanks. To prepare a quotation, please share the following five items where available:
Drawings: 2D technical drawings and available 3D CAD files of the required ring.
Component configuration: Inner or outer ring, geared or gearless design, and the relevant ball or roller raceway arrangement.
Material: Specified 42CrMo4, 4140, 50Mn, carbon steel, cast steel, ductile iron or another approved grade.
Key dimensions: Outside diameter, inside diameter, height, mounting-hole arrangement, raceway details and gear interfaces where applicable.
Order scope: Estimated quantity, intended equipment and whether a forging blank, casting or finished ring is required; include load requirements if specified.
Additional heat treatment, inspection and documentation requirements can be included in the approved technical documents. SIMIS will quote the agreed material, process and finished supply condition.
Send your OEM slewing bearing ring drawings and inquiry to SIMIS: info@simis-group.com
