How Many People Does a 10-Press Moulding Shop Really Need per Shift? (₹ Crew Maths, India)
How many people does a 10-press injection moulding shop really need per shift? There is no fixed ratio: it depends on how many seconds of hand work each cycle needs. As of 17 Oct 2026, on assumed job mixes, a 10-press shop needs about 10 to 14 people a shift. On illustrative minimum-level wages, the 4-head gap costs roughly ₹2.2 lakh a month across three shifts.
Last checked: 17 Oct 2026.
By the Mama Editorial Team. For promoters and plant heads of Indian moulding units. How to work out the crew for your own job mix, and what it is worth in rupees.
Key takeaways
- Size the crew by work content, not by press count. An operator is needed for the seconds of hand work in each cycle: picking, degating, inserting, inspecting, packing. Divide that by cycle time and you get the fraction of a person each press needs.
- Auto-drop jobs and manual-pick jobs need very different crews. On our assumptions, an auto-drop press with a conveyor needs about 0.2 of an operator, and an insert-moulding press needs nearly a full one.
- Indirect roles are fixed per shift. A setter, a QC inspector, a material handler and a shift in-charge are needed whether 6 or 10 presses run, so idle presses make them more expensive per part.
- A wage line makes every head visible. On an assumed ₹585 a day for a semi-skilled operator and ₹535 for an unskilled helper (illustrative), each extra head costs ₹17,000–19,000 a month all-in.
- Count heads in aggregate. You are sizing a crew, not ranking operators. Keep numbers at press-bay and shift level, and give workers proper notice before any counting.
Why "one operator per machine" is the wrong rule
The common rule of thumb is one operator per press. It is easy to plan and easy to explain to a contractor. It fails because a press does not need a person. A job does.
The same 150-tonne press can run a cap mould that drops parts onto a conveyor, then a cold-runner mould that someone must degate and pack every 25 seconds, then an insert job where an operator places a brass bush before every shot. Same press, completely different crew.
Even the government's own small-unit profiles never assumed one-per-machine. An older DC-MSME project profile for injection-moulded plastic items, written for the PMRY self-employment scheme, staffs a two-machine unit (60 g and 15 g) with one skilled and one unskilled worker on an 8-hour shift (Office of the DC-MSME, project profile "Injection Moulded Plastic Items"). People are allocated to work, not to machines.
The four jobs on a moulding floor
Before the maths, separate the crew into what they actually do:
- Press operators. Remove or watch parts, check, degate, load inserts, pack.
- Helpers for secondary work. Deflashing, assembly, printing, packing into master cartons, often at a bench away from the presses.
- Indirect roles per shift. Mould setter, QC inspector, material handler (dryer, hopper, regrind) and shift in-charge.
- Relievers. Someone covers breaks and absences, or presses stop.
Most crew arguments mix these groups up. An owner sees 14 people for 10 presses and says "too many"; the production manager says "too few". Both can be right.
The work-content method: seconds of hand work ÷ cycle time
For each running job, time three things for a few cycles:
- Cycle time (from the press display or the job card), in seconds.
- Hand work per shot, in seconds: picking, degating, insert loading, inspecting and packing that the operator must do for each shot.
- Whether the operator must stay at the press. Insert loading and manual pick with the gate open usually tie the operator to one press. Auto-drop does not.
Operator load per press = hand work ÷ cycle time. Add an allowance for walking, breaks and small stoppages; we assume 15%.
The table below uses assumed times for illustration, not data from any plant. Replace them with a stopwatch on your own floor.
| Job type (assumed) | Cycle time (s) | Hand work per shot (s) | Operator load per press | With 15% allowance |
|---|---|---|---|---|
| Auto-drop to conveyor, bulk packing (caps, closures) | 20 | 3 | 0.15 | 0.17 |
| Robot or sprue picker, operator inspects and packs | 30 | 6 | 0.20 | 0.23 |
| Manual pick, degate and pack (multi-cavity, cold runner) | 25 | 12 | 0.48 | 0.55 |
| Large part, manual pick, trim flash, stack | 45 | 25 | 0.56 | 0.64 |
| Insert moulding (operator places insert every shot) | 30 | 20 | 0.67 | 0.77, and tied to the press |
Two things follow from this table.
First, auto-drop and picker jobs let one operator cover 3 to 5 presses, if the presses are adjacent and packing is simple. Spread them across the shop and walking eats the gain.
Second, insert and heavy manual-pick jobs need close to one person per press, who can't be shared because the press waits for them every cycle.
Worked ₹ example: a 10-press shop, crew of 14 vs 10
Assumptions (all illustrative): 10 presses of 80–250 tonnes in Maharashtra Zone I; three 8-hour shifts; 26 paid days a month; operators classed semi-skilled, helpers unskilled. We add an assumed 25% to the minimum wage for employer PF, ESI, bonus and leave; that 25% is our estimate, not a statutory figure. Assume ₹585 a day for a semi-skilled operator and ₹535 for an unskilled helper (₹15,210 and ₹13,910 a month over 26 days; illustrative). Take the current schedule for your trade and zone from the Maharashtra Labour Commissionerate; most states revise the DA part twice a year.
Job mix A (manual-heavy): 4 manual-pick, 2 large-part, 2 insert, 2 auto-drop jobs. Work-content load from the table: 4 × 0.55 + 2 × 0.64 + 2 × 0.77 + 2 × 0.17 = 5.36, so about 6 operators, with the two insert presses each holding one person.
Job mix B (automated): 6 auto-drop, 3 picker, 1 manual-pick. Load: 6 × 0.17 + 3 × 0.23 + 0.55 = 2.26, so 3 operators if the presses are grouped.
| Role per shift | Crew for mix A (heads) | Crew for mix B (heads) |
|---|---|---|
| Press operators | 6 | 3 |
| Trimming / packing helpers | 4 | 3 |
| Mould setter | 1 | 1 |
| QC inspector | 1 | 1 |
| Material handler (dryer, hopper, regrind) | 1 | 1 |
| Shift in-charge | 1 | 1 |
| Total | 14 | 10 |
The difference is 3 operators and 1 helper per shift.
| Cost line (assumed wages, 25% on-cost) | Value (₹) |
|---|---|
| Semi-skilled operator, all-in per month | 19,013 |
| Unskilled helper, all-in per month | 17,388 |
| Gap per shift (3 operators + 1 helper) | 74,425 |
| Gap per month, three shifts | ~2,23,300 |
| Gap per year | ~26.8 lakh |
Read the result the right way round. Neither crew is wrong. Fourteen people is the right crew for mix A, and 10 is right for mix B. The waste appears when the job mix moves from A towards B and the crew stays at 14. The reverse is worse: a crew of 10 on mix A leaves presses waiting for hands. For the shift-level loss model on a moulding floor, see cameras in injection-moulding units.
To turn this into ₹ per part, put your crew cost and output into the labour cost per piece calculator.
The indirect roles that don't shrink
Setters, QC, material handling and supervision are fixed per shift: 4 of the 10 heads in mix B. Two consequences:
- Idle presses raise indirect cost per part. With 3 of 10 presses waiting, the same 4 indirect heads serve 7.
- Mould changes drive setter workload. With many short runs, presses wait for the setter, and it shows up as long changeovers, not as a staffing gap.
Overtime is not a cheap way to run short
If the crew is set too lean for the job mix, the gap is usually filled with overtime. Under the Occupational Safety, Health and Working Conditions Code, 2020, in force since 21 November 2025, overtime needs the worker's consent and is paid at twice the rate of wages (s.27), (OSH Code, Gazette of India, 2020). The Code on Wages, 2019 sets the overtime rate at not less than twice the normal rate of wages (s.14) (Code on Wages, Gazette of India, 2019). Your state's rules set the overtime ceiling. For how the Codes treat shifts and overtime in a mid-size plant, see labour codes for a 200–1000 worker plant.
An operator "saved" and covered by daily overtime is the same work at double the rate, by a more tired person.
How to set your own crew in one week
- List the jobs that will run next month, press by press, from the production plan, not from last month.
- Time hand work and cycle for each job. Five cycles per job per shift is enough. Note whether the operator is tied to the press.
- Compute load per press and add up by bay. Group presses that can share an operator (adjacent, auto-drop or picker, simple packing).
- Add the fixed indirect roles and a reliever for every 8–10 direct heads to cover breaks and absences (our assumption; set your own from your absence rate).
- Compare with the muster. If the muster is higher, find where the extra hours go. If it is lower, find which presses wait for people.
- Recheck whenever the job mix changes: a new picker, a hot-runner conversion or an insert job ending.
The same logic applies outside moulding. For the corrugated-box version, see corrugator crew size, and for machine shops that staff two people per machine, see two people per machine.
Where the industry stands
Indian moulding is mostly small and mid-size. The All India Plastics Manufacturers' Association says 90% of its membership is from the MSME sector, and it counts over 22,000 members through affiliated associations (AIPMA, "Know your association", checked 17 Oct 2026).
The DC-MSME profile cited above sets no norm for operators per press, and we found no Indian norm elsewhere (checked 17 Oct 2026). Treat any ratio you hear as one shop's habit.
What cameras can and cannot tell you here
A camera over a press bay reads two things well: whether each press is cycling, idle or open, and roughly how many people are in the bay. Over a week that gives "presses running vs heads present" by shift, including the moments when presses stand open waiting for someone.
What it cannot do:
- Time hand work precisely. Seconds per shot need a stopwatch or the press controller's cycle log.
- Know your job card. It does not know that press 7 is on an insert job unless someone tells it.
- Judge whether someone is working. An operator standing at a press may be inspecting parts, which is real work.
- Replace the setter's judgement on mould condition or process settings.
- Identify or rank people. It shouldn't. Measure the crew, not the person. Footage of recognisable workers is personal data under s.2(t) of the DPDP Act, 2023; tell workers in writing what is recorded and why (see the worker CCTV notice under DPDP).
Where Mama fits
Mama watches the press bays through the cameras a plant already has, or ones added for it, and sends the owner a short plain-language note each morning: how long each press ran, stood idle or waited with the gate open yesterday, and how many people were in each bay in each state, as totals only. It watches machines and flows, doesn't name or rank anyone, and doesn't decide your crew size for you. To see what that would look like for your shop, see askthemama.com or leave an email or phone in the form below, and Mama will get back to you with where the hours seem to leak and where cameras would need to go.
FAQ
How many operators does an injection moulding machine need? It depends on the job. An auto-drop or picker job may need a fifth of an operator, so one person covers 3–5 grouped presses. An insert or heavy manual-pick job needs close to one per press.
How many people does a 10-press moulding shop need per shift? On our assumed job mixes, about 10 to 14 including a setter, QC inspector, material handler and shift in-charge. Work it out from timed hand work per shot divided by cycle time.
Which wage should I use for the crew calculation? Your own payroll cost per head, never below your state's current minimum wage for your trade, skill and zone. The ₹585 and ₹535 a day used here are illustrative. Maharashtra publishes its schedules through the Labour Commissionerate, and most states revise the DA part twice a year.
Is a robot picker cheaper than an operator? Compare the robot's quote with the operator hours it frees across all shifts: on the example above, about ₹19,000 a month per shift for a semi-skilled operator on the assumed wage and 25% on-cost. It pays back only if the freed operator moves to other work or is not hired.
Can I cover a short crew with overtime? Only with the worker's consent, and overtime is paid at twice the rate of wages under the OSH Code and the Code on Wages, within the overtime ceiling your state's rules set.