Conveyor belt splice inspection checks
Straightness over the splice, belt run-out near it and the thickness difference between the two belt ends.
Result
How it works
A splice that is not straight makes the same section of belt run off all the way round the conveyor. Three quick measurements after splicing catch most geometry problems before the belt goes back into service.
Straightness: stretch a line along the belt centre over at least 5 m across the splice and measure the largest offset. Run-out: watch the belt edge within 15 m of the splice on the first runs (from a guarded position). Thickness: measure both belt ends next to the splice.
Formula
Straightness: H ≤ k × AD (k = 0.002 in one maker instruction) Run-out ≤ min(p % × BW, cap) within 15 m of the splice Thickness difference |t₁ − t₂| ≤ limit
| Symbol | Meaning | Unit |
|---|---|---|
| AD | Centre-line baseline across the splice (≥ 5 m) | mm |
| H | Largest offset from the line | mm |
| BW | Belt width | mm |
| t₁, t₂ | Belt thickness at each end | mm |
Worked example
Inputs: Straightness baseline AD = 5000 mm; Measured offset H = 11 mm; Straightness factor = 0.002 ratio; Belt width BW = 800 mm; Largest run-out near the splice = 20 mm; Run-out limit (% of BW) = 3 %; Run-out cap = 75 mm; Thickness, belt end 1 = 12.2 mm; Thickness, belt end 2 = 12.6 mm; Maximum difference = 3 mm.
- Straightness limit = 0.002 × 5000 = 10 mm; measured 11 mm → fail
- Run-out limit = min(3 % × 800, 75) = 24 mm; measured 20 mm → pass
- Thickness difference = |12.2 − 12.6| = 0.4 mm ≤ 3 mm → pass
- Result: straightness fails — investigate the splice centre line before running
Assumptions and limits
- Acceptance limits are your specification. The defaults come from one maker instruction (straightness) and one SANS-based splicing method (run-out, thickness) and can be edited.
- Static checks do not prove splice endurance. Keep the cure log and watch the first runs from guarded positions.
- Isolate and lock out the conveyor before measuring on the belt.
Screening estimate, not a design approval. Verify measured inputs, current standards, manufacturer limits and site procedures before purchasing, cutting or installation. Isolate and lock out equipment before any hands-on measurement.
Questions
How straight should a splice be?
One maker’s limit is an offset of no more than 0.002 × the baseline — 10 mm over 5 m.
The belt runs off only at one place on the structure — is it the splice?
Usually not. A fault at one fixed place points to idlers, structure or loading; a fault that travels with the belt points to the splice.
Source notes
- Straightness H ≤ 0.002 × AD: Sempertrans Sempercord General Splicing Instruction V a / 12.2020 p.22. Run-out ≤ 3 % of belt width (max 75 mm) within 15 m and thickness difference ≤ 3 mm: SANS-based splicing method (Van Staden). Summarised in original words.
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