The term support ring refers to a ring-shaped bearing that distributes forces over a wide area, stabilizes components, and holds tools in position. In concrete demolition, natural stone extraction, as well as rock and tunnel construction, a support ring is an important functional detail—such as on rock and concrete splitters or as a bracing element on fixtures. In conjunction with products from Darda GmbH such as rock and concrete splitters, concrete demolition shears, or other hydraulic excavator attachments, a support ring supports safe force transmission, reduces edge spalling, and contributes to reproducible work results—without being the center of attention itself, yet with a clear influence on process stability and component protection.
Definition: What is meant by support ring
A support ring is a ring-shaped component (also described as support ring, bearing ring, or abutment ring) that serves as a bearing and force distributor. It increases the contact area between tool/fixture and the material surface, reduces local stresses, and stabilizes the position of the applied device. Typical designs are made of tempered steel or high-strength alloys, with adapted radii, chamfers, or profilings to protect the bearing surface. In practice, the support ring appears, among other things,
- as a bearing and reaction ring at the mouth of a borehole when a splitter cylinder introduces forces into concrete or rock,
- as a ring-shaped bracing element on fixtures during coring and cutting,
- as a ring-shaped bearing on attachments that introduces loads into components or guides movements.
Function and operating principle in concrete and rock demolition
The support ring distributes reaction forces, protects component edges, and ensures the alignment of the tool. In concrete demolition and special demolition as well as in rock excavation and tunnel construction, high point loads are often introduced at small contact areas. A ring-shaped bearing surface creates a larger, defined support zone and thus reduces the risk of breakouts in the edge area.
Force distribution at the borehole edge
When splitting concrete or natural stone, high reaction forces arise between splitting wedges, counter-wedges or springs, and the surrounding material. A support ring introduces these forces as a closed ring into the edge area of the borehole. The more areal load transfer minimizes local overloads and reduces follow-up damage such as edge spalling—an advantage if concrete demolition shears or attachment shears are used subsequently and defined edges are beneficial.
Stabilization and alignment
In addition to load distribution, the support ring stabilizes the tool’s seating. It helps align the longitudinal axis of splitter cylinders with the borehole axis and prevents canting. This benefits the dimensional accuracy of the split path, especially in fit-up areas where precise separation with Multi Cutters, steel shears, or tank cutters is planned.
Support ring on rock and concrete splitters
Rock and concrete splitters from Darda GmbH use boreholes as a reaction space. A suitable support ring—designed as an integral bearing of the splitter cylinder or as an applied bracing element—bears on the borehole mouth or the adjacent component surface. This safely introduces the splitting force into the component while protecting it at the same time. This is relevant in the following applications:
- Concrete demolition and special demolition: controlled release of components without unwanted cracks in adjacent areas,
- Rock excavation and tunnel construction: defined force transmission in brittle rock, reduction of edge breakouts in critical zones,
- Natural stone extraction: reproducible split lines during block detachment, lower reject rates due to gentle edge support.
Borehole edge, bearing conditions, and surfaces
The function of the support ring stands and falls with the quality of the bearing surface. A flat, clean environment around the borehole, appropriate edge treatment (chamfer or small radius), and a ring radius adapted to the material reduce stress peaks. The pressure between ring and substrate should be distributed so that neither indentations nor slipping occur.
- Create and clean the borehole (remove loose particles).
- Deburr or slightly break the edge of the borehole to reduce notch effects.
- Align the splitter cylinder, seat the support ring with full-surface contact, check alignment.
- Let the hydraulic pressure rise evenly; observe reaction movements.
- After splitting, visually inspect the bearing zone.
Relation to concrete demolition shears and other attachments
With concrete demolition shears from Darda GmbH, the crushing process is the focus; nevertheless, supporting, ring-shaped bearing or abutment surfaces influence the work result—e.g., when setting up on edges, walls, or slabs. A clean borehole edge zone preserved by the support ring from preceding splitting work facilitates targeted gripping and breaking. The same applies to attachment shears and Multi Cutters when gutting and cutting tasks are performed on pre-split components.
Combination in practice
A typical sequence can be as follows: pre-splitting with a splitter (the support ring protects the edge and stabilizes the seating), then crushing the freed segments with a concrete demolition shear. This reduces uncontrolled cracks, minimizes secondary damage, and supports clean construction logistics. In the metal sector, the principle of controlled load distribution via ring-shaped bearing surfaces also remains important when working with steel shears or tank cutters on adjacent concrete structures.
Selection criteria: sizing, material, and surface
The design of a support ring is guided by the tool, the material, and the process. The goal is a robust, low-wear bearing with forgiving contact behavior.
- Material: tough-hardened steels or tempered alloys; surface treatment if required.
- Geometry: sufficiently wide bearing surface, adapted chamfers/radii to reduce stresses.
- Surface: smooth, flat, and free of scoring; defined roughness for a secure seat.
- Contact pressure: avoid exceeding local compressive strengths of the substrate.
- Environment: corrosion protection in moisture/chlorides; ensure temperature and chemical resistance.
- Compatibility: match interface dimensions to the splitter cylinder, shear, or fixture.
Relevant interface dimensions
Important are outside diameter and bearing width (influence pressure and stability), inside diameter or reliefs (adaptation to tool contours), as well as flatness, runout, and form tolerances of the ring. A defined chamfer or a small radius at the ring edge prevents notch effects at concrete edges or natural stone surfaces.
Installation, inspection, and maintenance
A support ring is subject to wear. Regular inspections and correct installation ensure functionality over the entire service life.
- Preparation: clean bearing surfaces, document damage.
- Installation: position the ring free of stress, establish full-surface contact.
- Function check: trial stroke with low load; check seating and alignment.
- Inspection: after load cycles, check for cracks, indentations, distortion, corrosion.
- Servicing: remove light burrs, replace damaged rings in good time.
Typical failure patterns
- Edge spalling on the component due to a bearing that is too narrow or too hard without radius/chamfer,
- Indentations and scoring on the ring caused by foreign particles or excessive local pressure,
- Cracking in the ring due to overload or notches,
- Distortion due to improper installation or thermal effects,
- Corrosion with subsequent notch sensitivity and increased wear.
Occupational safety and legal notes
The safe use of a support ring requires qualified personnel, suitable personal protective equipment, and compliance with the manufacturer’s instructions. Load paths must be kept clear of people; chipping and unpredictable movements must be expected. Test and maintenance intervals should be documented. Legal requirements may vary by country and application; binding requirements are to be taken from the recognized rules of technology and applicable regulations. These notes are general in nature and do not replace a case-by-case assessment.
Fields of application and typical scenarios
In building gutting and cutting, ring-shaped bracing elements on drilling and cutting fixtures provide stabilization, supporting precise follow-up work with concrete demolition shears or attachment shears. In concrete demolition and deconstruction, the support ring protects edges during pre-splitting so that subsequent work steps remain plannable. In rock excavation and tunnel construction, it promotes controlled split initiation along desired lines. In natural stone extraction, it contributes to the quality of block separations. In special operations—such as in confined spaces or sensitive environments—the support ring helps introduce reaction forces in a targeted and gentle manner.
Interaction with hydraulic power packs
Hydraulic power packs from Darda GmbH supply the working pressure for splitter cylinders, concrete demolition shears, and other tools. Even pressure build-up reduces impact loads on the bearing and supports the function of the support ring. Clean hydraulic oil, proper hose routing, and adherence to operating parameters indirectly help protect bearing surfaces and component edges.
Quality assurance and documentation
For recurring tasks, simple documentation of bearing conditions, inspection results, and parameters used is worthwhile. Photos of the borehole environment, measured values for flatness, and short notes on material, ring geometry, and observed wear improve reproducibility—a solid basis for consistent results in concrete demolition, rock work, or natural stone extraction using Darda GmbH tools.