| Compact pivot or hinge bore | 25–50 mm (1.0–2.0 in) | 50–150 mm (2.0–5.9 in) | Check axial entry clearance at both ends, nearby brackets, and room for the drive unit. | Compact portable system with a short boring bar and rigidly mounted supports. | Confirm the machine’s minimum boring diameter and that the bar, cutter, and supports fit through the available opening. |
| Medium equipment pin bore | 50–150 mm (2.0–5.9 in) | 150–500 mm (5.9–19.7 in) | Measure the distance between bore faces and the radial clearance around the work area. | Portable line boring setup with adjustable support positions and a bar matched to the bore length. | Check the machine’s diameter range, bar working length, support spacing, and available feed travel. |
| Long articulated joint or linkage bore | 75–200 mm (3.0–7.9 in) | 500–1,000 mm (19.7–39.4 in) | Measure the full span between mounting faces and identify surfaces suitable for securing each support. | Long-bar configuration with multiple rigid support points where the machine design allows them. | Use the manufacturer’s permitted bar span and support arrangement; long unsupported spans can reduce cutting stability. |
| Large structural or heavy-equipment bore | 150–300 mm (5.9–11.8 in) | 300–800 mm (11.8–31.5 in) | Check access for the bar, bearing supports, drive head, and tools used to mount and align the machine. | Heavy-duty portable system with a bar and supports rated for the required diameter and cutting load. | Verify the machine’s maximum boring diameter, mounting capacity, available torque, and the workpiece’s mounting rigidity. |
| Restricted-access bore near surrounding components | Measure the actual bore; for example, 40–120 mm (1.6–4.7 in) | Measure the actual face-to-face distance; for example, 100–400 mm (3.9–15.7 in) | Record the smallest opening, side clearance, overhead clearance, and whether the bar can enter from either end. | Low-profile or modular configuration, selected to suit the available entry path and mounting locations. | Compare the complete setup envelope—not just the bar diameter—with the available space around the workpiece. |
| Multiple bores requiring alignment | Record the diameter of every bore; for example, 50–150 mm (2.0–5.9 in) | Measure each bore’s width and the center-to-center distance between bores. | Check whether one bar can pass through all bores and whether supports can be positioned without obstruction. | Through-bar setup with a suitable alignment method, such as a precision alignment mandrel or measurement system. | Define the required centerline alignment and tolerance before choosing the machine and setup method. |