Cast Crane Drum
Cast crane drum for heavy-duty overhead crane applications (50–400 t, A6–A8). Available in cast, welded and cast-steel options for ≥300°C metallurgical environments. 100% NDT on critical areas, rope-groove accuracy IT8–IT9, dynamic balance ≥ G16.
Key Features
Supports 50–400 t rated capacity and A6–A8 working classes.
Material options: cast iron / ductile iron / cast steel / welded shell (Q345B + 45 steel shaft).
100% NDT on critical areas; rope-groove accuracy IT8–IT9; dynamic balance G16 when line speed > 10 m/s.
Structural Options & Typical Overhead Applications
Cast crane drum — compact, high rigidity — preferred for standard and mid-size overhead crane drums.
Welded drum — lighter weight and feasible for very large diameters (transport/weight constraints).
Flange-coupled (gear-hub) — ideal for bridge-style overhead cranes where shaft bending is the primary load.
Rim-gear drive — suitable for high reduction ratios or space-limited reducer layouts.
Dual/compound drums — counter-wound grooves for synchronized dual-rope lifting systems.
Material Selection Rules
Rated ≤ 50 t & working class ≤ A5 → HT200 / HT250 (gray cast iron).
Rated > 50 t or working class > A5 → ZG270-500 (cast steel) or higher.
High-impact/shock → QT400-18 (ductile iron with high toughness).
High-temperature ≥ 300°C → ZG310-570 (heat-resistant cast steel).
Large diameter / weight-limited → Q345B welded shell + 45 steel short shaft.
Manufacturing Process & Quality Control Highlights
Core workflows
Cast drums: pattern & mold → sand / lost-wax casting → melt 1350–1450°C → pouring → shakeout → stress-relief / anneal → rough machining → stress removal → finish machining → rope-groove machining (precision IT8–IT9) → surface inspection.
Welded drums: plate rolling → circumferential / longitudinal welding → NDT of welds → short-shaft assembly → overall machining → groove forming.
Critical inspection criteria
Dimensional tolerance checks with CMM (diameter, length, groove pitch).
Geometric tolerances: cylindricity, coaxiality to bearing bores.
Surface roughness measurement per Ra targets.
NDT: castings must be free of cracks/shrinkage; welds 100% radiographic/ultrasonic and supplemented by magnetic particle/ultrasonic tests.
Dynamic balance test if linear speed > 10 m/s: target balance grade ≥ G16.
Installation & Maintenance
Installation highlights
Rope anchorage: use clamping plate with ≥2 bolts; reserve ≥2 safety wraps on drum.
Layer winding: multi-layer applications require rope guiding device; maintain rope entry angle < 3.5°.
Coupling clearance: coupling/gear-hub to reducer output shaft axial play ≤ 0.1 mm to prevent axial shifting.
Maintenance schedule
| Interval | Action | Acceptance criteria |
|---|---|---|
| Every shift | Visual check: groove wear, rope lay, bolt tightness | No rope jump, no loose fasteners |
| Every 200 hours | Bearing lubrication (manufacturer-specified grease) | Adequate lubrication, no dry friction |
| Every 500 hours | Comprehensive inspection + drum wall thickness measurement | Uniform wall thickness, no abnormal thinning |
| Every 2000 hours | NDT at stress concentration points | No fatigue cracks or hidden defects |
Common faults & corrective actions
Fatigue cracks on drum — cause: cyclic load, stress concentration → action: retire and replace (welding repair prohibited).
Severe groove wear (>20% wall loss) — cause: poor lubrication or overloading → action: replace drum.
Rope crossover / irregular layering — cause: failed guide or excessive entry angle → action: repair guide device, realign rope to <3.5°.
Axial shaft movement — cause: loose bearings or worn coupling → action: tighten bearings, replace worn transmission parts.
Contact Us for specific Details & PDFs !
FAQs
Q: What is your policy on repairing drums with cracks or severe wear?
A:Fatigue cracks: drums are retired and replaced; welding repairs are not permitted for fatigue cracks. Severe groove wear (over 20% wall loss) requires drum replacement.
Q: How are fatigue cracks prevented and detected?
A: Prevention: design to minimize stress concentrations, perform stress-relief heat treatment and correct material selection. Detection: scheduled NDT (ultrasonic/radiographic) at stress concentration zones; we perform 100% NDT on critical areas.