Ports, mounting, and drawing approval
How to identify hydraulic ports, measure mounts, and approve a replacement or custom cylinder drawing.
Port identification
Measure thread major diameter and pitch, identify parallel or tapered form, and inspect the sealing method: O-ring boss, bonded washer, 24° cone, 37° flare, face seal, thread sealant, or flange. Do not force a gauge or rely on country origin.
Port position and hose sweep
Record port angle relative to the mounts, distance from end features, wrench access, hose bend radius, and movement through the complete stroke. A correct thread in the wrong orientation can make the cylinder unusable.
Mount measurements
Measure pin centre, pin diameter, lug width, bracket gap, bushing length, shoulder position, spherical bearing size, and grease path. Record whether the rod end can rotate and whether the machine constrains rotation.
Drawing comparison
Overlay old and proposed dimensions, check closed and extended states, and list every deviation. Use revision letters, dates, units, tolerances, and approval signatures. A 3D model is useful for interference, but the controlled 2D drawing should state manufacturing and inspection requirements.
Replacement boundary
Similarity of appearance or nominal bore/stroke is not interchangeability. Ports, mounts, stop length, gland, cushioning, valve blocks, sensors, and pressure fatigue can differ.
Approval record
Keep the buyer drawing, supplier drawing, markups, calculation notes, photos, and final approval in one project record. If any critical value remains unknown, mark it “not stated” or “needs review” rather than filling the gap.