Work it out.
Calculators
Is my epoxy and isocyanate certificate valid?
BEK 1978/2021 § 16, § 30, subsections 7-8 + annex 10
Butt welding of PE pipes
DVS 2207-1 (as at 2023), via SIMONA work.info 10/2023
Clamping force in injection moulding
Tryk x areal (kraftberegning)
Shrinkage and tool dimensions
Svindformel S=(D-M)/D
Fibre weight percentage in laminate
Massebrøk (procentregning)
MEKP hardener for polyester resin
Producentdatablad (typisk ca. 1–2 vægt% MEKP, maks. ca. 3%)
Epoxy: resin/hardener mixing ratio
Producentdata (West System 105/206-datablad)
Laminate thickness from glass fibre layers
Kompositfysik (arealvægt-metode) — E-glas/harpiksdensitet
Gelcoat consumption per m²
Producentdatablad (NM Gelcoat, ca. 500 g/m² pr. lag)
Sandwich panel weight (foam core + laminate)
Producentdata (Diab Divinycell H-densiteter) + materialedensitet
Wall thickness in rotational moulding
Massefylde/geometri (ARM Design Guide, rotationsstøbning)
Extrusion: line speed
Massebevarelse (ekstruderingsfysik)
Welding rod consumption for plastic welding
Geometri (fugevolumen/rundt tværsnit)
Injection moulding: cooling time
Sprøjtestøbningsteori (Menges/Michaeli-køletidsligning)
Injection moulding: cycle time and capacity
Forholdsregning (kapacitetsplanlægning)
PE pipe: pressure class (SDR/PN)
ISO 12162 / DS/EN 12201 (PE-trykrør)
Part weight from volume and material
Materialedatablade (typiske densiteter)
Shot weight and dosing path
Conservation of mass · manufacturers' rule of thumb: dosing distance approx. 1–3 × screw diameter
Regrind in circulation
Geometric series: proportion processed at least n times = rⁿ
Drying hopper: can it manage to dry the granulate?
Residence time = funnel content ÷ consumption · drying time from material's data sheet
Unit price for an injection-moulded part
Competence objective: calculation of manufacturing costs
Funnel and hopper
Exact flat pattern
Tub with fall and drain
Exact flat pattern
Channel and trough with fall
Exact flat pattern
Strip layout for a stamping die
Exact flat pattern
Tools that work in all subjects
Whatever your programme is called, these tools calculate the same — Pythagoras, area, percentages and units are not tied to one trade.
- Pythagorasa² + b² = c²Find the missing side, set out a right angle, check whether a room is square, and find the space diagonal.
- Area and perimeterm²Rectangle, triangle, trapezium, circle and composite shapes — area and perimeter.
- Volume and surface aream³ · lBox, cylinder, cone, sphere, pyramid, prism, pipe and frustum — also in litres.
- Percent%Percentage of, how many per cent, percentage change, discount and VAT.
- Scale and ratios1 : 50From drawing to reality, area and volume to scale, the rule of three and dividing in a ratio.
- Unit convertermm ↔ mFrom mm to km, Pa to bar and kB to GB — with the unit staircase.
- Time calculations and the clockt : minTime between two clock times, add time, and 1.75 h = 1 h 45 min for the timesheet.
- Slope and fall% · ° · 1:xFall from level to level, in per cent, per mille, degrees and mm per metre — and the height difference.
- Material consumption including wastem² + %Boards, paint, battens at c/c spacing and packs — for a composite surface or a whole room, with waste.