Calculator Inputs
Example data table
| Material | Thickness (mm) | Pressure (psi) | Abrasive (kg/min) | Quality | Length (mm) | Speed (mm/min) | Total time (min) |
|---|---|---|---|---|---|---|---|
| Mild steel | 12 | 60000 | 0.35 | Standard | 1200 | ~300–450 | ~3.0–4.6 |
| Aluminum | 10 | 55000 | 0.32 | Fine | 1800 | ~450–700 | ~3.0–4.5 |
| Granite / stone | 20 | 65000 | 0.40 | Standard | 900 | ~120–220 | ~4.5–8.0 |
Formula used
This calculator uses an empirical traverse‑speed model built from common waterjet trends. A reference speed is adjusted by normalized settings and practical modifiers:
v = v × Q × E × Edge × Taper × Abrasive × Pump ÷ (T/T0)d
- v is cutting speed.
- P is pressure; O orifice diameter; M mixing tube diameter.
- A is abrasive flow; S is standoff; T is thickness.
- Q is quality factor; E is efficiency; other factors reflect edge, taper control, abrasive type, and pump condition.
How to use this calculator
- Select a unit system and choose the material.
- Enter thickness, pressure, nozzle sizes, and abrasive flow.
- Pick a quality level and optional taper control requirement.
- Provide cut length plus lead‑in and kerf allowances.
- Set pierce count, pierce time, and handling allowance.
- Optionally enter rates to estimate total cutting cost.
- Press Calculate to view results above the form.
- Download CSV or PDF for quoting and job tracking.
Notes for construction workflows
- Use higher quality when parts must fit field assemblies.
- For thick plate, prioritize stable pressure and fresh nozzles.
- Standoff control matters on uneven or warped stock.
- Track abrasive and water use for remote site logistics.
Accurate settings reduce waste and keep projects on track.
Professional article
1) Why cutting speed matters on site
Waterjet traverse speed directly affects schedule reliability, fit-up quality, and total job cost. In construction fabrication, a small speed change can shift delivery dates when hundreds of meters of cut path are involved. Use speed estimates to decide whether to pre-cut in the shop, subcontract, or sequence field work differently.
2) Typical pressure and nozzle ranges
Modern systems commonly run between 35,000 and 90,000 psi, with many shops centered near 60,000 psi for balanced wear and productivity. Orifice diameters around 0.25–0.35 mm and mixing tubes around 0.76–1.02 mm are frequent starting points. Larger nozzles can boost speed but may widen kerf and increase consumable cost.
3) Thickness drives the biggest penalty
Thickness is the primary limiter because the jet must maintain energy density through the full depth. Doubling thickness rarely doubles time; it often increases time by more than 2× depending on material and quality requirements. This calculator applies a thickness exponent so planning remains conservative for thicker plate and stone.
4) Abrasive flow and mesh selection
Abrasive mass flow is a major lever for speed and edge condition. Coarser garnet (for example 80 mesh) generally supports faster removal, while finer abrasive can improve finish at reduced speed. Typical flows of 0.25–0.45 kg/min are common; higher rates can help thick metals but raise operating cost quickly.
5) Quality settings and taper control
Higher quality passes trade speed for straighter walls and smoother edges. If taper compensation is required for tight-fit brackets and connection plates, expect an additional reduction in traverse speed. When tolerances are relaxed for embeds or non-critical openings, draft or standard settings can shorten cycle time.
6) Standoff, pierce time, and handling allowances
Real parts include pierces, lead-ins, and repositioning time. Standoff that is too large reduces jet effectiveness, especially on warped stock. Pierce time can dominate on nested parts with many holes; a few seconds per pierce scales into minutes across large batches. Handling allowance captures fixture changes, slat strikes, and operator checks.
7) Cost drivers you can control
Shop rate converts total time into an easy budget line item, while abrasive, water, and electricity complete the operating picture. Abrasive usually dominates variable cost for abrasive cutting, so validating flow rate and abrasive price is important. Tracking kWh is helpful for remote generators and sustainability reporting.
8) Using results for quoting and planning
Treat the calculated speed as a planning baseline, then calibrate it with one short trial cut on your machine. Save CSV or PDF outputs for quotes, change orders, and progress documentation. Over time, adjust nozzle wear assumptions and efficiency to match your crew and maintenance cycle.
FAQs
1) Why does higher quality reduce cutting speed?
Higher quality targets require smoother surfaces and less striation, so the jet must move slower to maintain edge finish and dimensional control through the full thickness.
2) Which input changes speed the most?
Thickness usually has the largest impact. Pressure and abrasive flow help, but thick material demands much more energy to keep a clean kerf from top to bottom.
3) What abrasive flow is typical for general work?
Many shops run roughly 0.25–0.45 kg/min, depending on nozzle size and material. Higher flow can improve cutting on thicker metals, but it increases consumable cost.
4) Should I use metric or imperial units?
Use whichever matches your drawings. The calculator converts lengths and speeds automatically, while pressure stays in psi because that is a common pump specification in many shops.
5) How do pierces affect total time?
Pierces add fixed time per start, so parts with many holes can spend more time piercing than cutting. Enter a realistic pierce time and pierce count for accurate totals.
6) Why include lead-in and kerf allowances?
Lead-ins stabilize the cut before the actual contour, and kerf allowance covers small extra travel around starts and ends. These small distances add up across many features.
7) Are the costs final for bidding?
No. Costs are estimates for planning and comparison. Validate with your shop rate, abrasive price, utilities, and a short test cut, then apply your usual overhead and margin.