New Mould Job, No New Press? The Press-Hours Check Before You Buy (₹)
Can you take a new mould job without buying another press? Count press-hours in the right tonnage class, not presses. As of 17 Oct 2026, a new 350–550-tonne servo press lists at about ₹44–59 lakh in Gujarat dealer listings, before auxiliaries. In our assumed 15-press example, a 300-hour-a-month job fits once mismatched moulds and idle hours are recovered.
Last checked: 17 Oct 2026
By the Mama Editorial Team. For moulding-unit owners with a new mould on the table and a production head saying "the big presses are full". If a bank loan is part of the plan, the expansion-loan capacity guide covers how a lender reads the same numbers. Every rupee figure is an assumption unless sourced.
Key takeaways
- Run three gates in order: tonnage, shot size, then press-hours. A press that can't clamp the mould or melt the shot doesn't count, however idle it is.
- Count free hours only on presses that can run the mould. "We have 15 presses" means nothing if only four have the clamp force and tie-bar room for this tool.
- Look for small moulds on big presses. A mould needing 200 tonnes that sits on a 350-tonne press is using up the hours the new job needs.
- The new press is a monthly bill, not a one-time price. At an assumed ₹60 lakh all-in, 75% financed at 10% over five years, the EMI is about ₹95,600 a month, before three operators at an assumed ₹16,900 a month each.
- In the worked example, recovered hours cover the job. Moving one mismatched mould, cutting mould changes from 4 to 2.5 hours and trimming idle time frees about 384 press-hours a month against the 300 the job needs.
Gate 1: can your presses clamp this mould
Clamp force is set by the part's projected area: the flat area of the parts and runner seen from the direction of injection, multiplied by a tonnage factor. Plastics Technology's 2017 column by RJG's Jeremy Williams says typical factors "range from 2 to 10 tons/in.2" and recommends 3 tons/in² as a starting point (Plastics Technology, 2017).
Assume the new job is a 10-litre PP paint pail, one cavity, with a projected area of about 102 in² (a pail roughly 290 mm across the top). At 3 tons/in² that is about 307 tonnes, so the mould belongs on your 350-tonne presses, not your 250s.
Two cautions:
- More tonnage is not free. Williams lists crushed vents, a rolled parting line, broken inserts and cracked core or cavity blocks as long-term effects of over-clamping (Plastics Technology, 2017).
- Many shops clamp at the maximum anyway. Fimmtech's Suhas Kulkarni wrote in 2023 that "most processors will set the tonnage to the max available on the machine — not an ideal scenario" (Plastics Technology, 2023).
Tonnage is not the only fit test. Check tie-bar spacing, mould height, opening stroke and ejector pattern against the mould drawing before the mould ships.
Gate 2: can the barrel melt the shot
A press with enough clamp force can still be the wrong press if the shot is too small or too large for its barrel. John Bozzelli's 2020 Plastics Technology column says: "Use 25% to 65% of the barrel capacity for your shot size." Below 25%, he writes, a uniform melt is unlikely. Above 65%, PP and PE "will literally grind metal off the flights of the screw" (Plastics Technology, 2020).
Assume the pail shot, part plus runner, is about 520 g and your 350-tonne presses have barrels of about 1,200 g in PP. That is 43% of capacity, inside the window. Use your injection-unit data sheet.
If the shot falls outside 25–65% on every press of the right tonnage, that is a real reason to buy, and no scheduling fixes it.
Gate 3: are there press-hours in that tonnage class
Now count hours, but only on the presses that passed Gates 1 and 2.
Job need per month:
Press-hours = (good parts ÷ cavities ÷ yield) × cycle time ÷ 3,600 + mould-change hours
Assume 36,000 good pails a month, one cavity, 97% good parts and a 28-second cycle. That is about 37,113 shots and 289 running hours. Add three mould changes at 3.5 hours each and the job needs about 300 press-hours a month.
Free hours:
Free hours = calendar hours − planned stops − hours running booked jobs − idle hours − mould-change hours
Most planning sheets stop at "calendar minus booked jobs". On a real floor, scheduled time also goes on presses standing with no operator, no material, no first-off approval or a mould on the bench. Our mould breakdown cost guide breaks down that last bucket.
The worked example: a 15-press shop and a 300-hour pail job
Assume a 15-press packaging moulding unit in Haryana, running three 8-hour shifts, six days a week. It has 6 presses of 150 tonnes, 5 of 250 tonnes and 4 of 350 tonnes. Only the four 350-tonne presses pass Gate 1 for the pail mould. All figures are assumptions for illustration.
| Per 350-tonne press, per month | Hours (h) | Basis |
|---|---|---|
| Calendar | 720 | 24 h × 30 days |
| Planned stops (Sundays, preventive maintenance) | 104 | 4 Sundays × 24 h + 8 h PM (assume) |
| Scheduled | 616 | 720 − 104 |
| Running booked jobs | 420 | from the controller's cycle log (assume) |
| Mould changes | 36 | 9 changes × 4 h door to door (assume) |
| Idle while scheduled | 140 | no operator, material, QC or mould (assume) |
| Free | 20 | 616 − 420 − 36 − 140 |
Across four presses that is 80 free hours against 300 needed, a 220-hour shortfall. On this table the production head is right: the big presses look full, and a fifth 350-tonne press looks like the answer.
Now look inside the 420 booked hours. Assume one press spends 150 hours a month on a crate-lid mould needing only about 200 tonnes; it went onto the 350 years ago and never moved back. Assume the 250-tonne presses have about 180 free hours between them.
| Lever (four 350-tonne presses) | Press-hours freed per month (h) | How |
|---|---|---|
| Free today | 80 | from the table above |
| Move the 200-tonne mould to a 250-tonne press | 150 | after a trial run on the 250 |
| Cut mould change from 4 h to 2.5 h | 54 | 9 changes × 1.5 h × 4 presses |
| Cut idle from 140 h to 115 h per press | 100 | 25 h × 4 presses |
| Total available for the new job | 384 | against 300 needed |
The job fits with 84 hours to spare. You can run the same arithmetic in the order capacity check calculator: enter only the presses that pass Gates 1 and 2, and use measured utilisation, not the planner's.
None of the levers is free. The mould move needs a trial on the smaller press. Faster mould changes need pre-staged moulds, preheated water lines and a crane on time. Idle hours fall only once you know which cause is biggest.
What the new press would actually cost you each month
Dated dealer listings show the price band. As of 17 Oct 2026, Ahmedabad's Sweith Industries lists servo injection moulding machines at ₹27.5 lakh for 250 tonnes, ₹44 lakh for 350 tonnes, ₹49.25 lakh for 450 tonnes and ₹58.82 lakh for 550 tonnes (Aajjo seller page, checked 17 Oct 2026). IndiaMART's servo moulding machine category shows a Vadodara listing for a 450-ton servo press at ₹52 lakh on the same date (IndiaMART, checked 17 Oct 2026). These are asking prices; the listings do not say what is included.
We found no published machine price list on the AIPMA or Plastindia Foundation websites (home pages and member listings checked 17 Oct 2026), so a dealer quotation is the only firm number you will get.
Assume an all-in cost of ₹60 lakh for a 350-tonne press with chiller share, dryer, hopper loader, foundation and installation, inside an assumed ₹40–80 lakh planning band for this size.
| Cost line | Option A: buy a 350-tonne press | Option B: recover hours on existing presses |
|---|---|---|
| Upfront cash | ₹15 lakh margin (25% of ₹60 lakh, assume) | ₹3–4 lakh for quick-change couplings, mould trolley and preheat station (assume) |
| EMI | ₹95,612/month: ₹45 lakh at 10% over 60 months (assume) | None |
| Interest over the loan | ≈ ₹12.4 lakh | None |
| Operators | 3 × ₹16,900 = ₹50,700/month (assume ₹650 a day × 26), before PF and ESI | Existing crew |
| Recurring fixed cash | ≈ ₹1.46 lakh/month | Little extra |
| First saleable pail | After delivery, foundation, installation and mould trial | After the mould move and first trial week |
| Hours left for the next job | The new press's free hours, minus its own idle and changes | 84 h on the 350s |
The operator rate is illustrative: ₹650 a day for a semi-skilled operator over 26 days. Take the current notification for your trade and zone from your state labour department (Haryana Labour Department).
At an assumed contribution of ₹1,000 per press-hour, the job is worth about ₹3 lakh a month either way. Option A spends about half of that on fixed cash; Option B keeps it, as long as the levers hold.
When buying the press is the honest answer
Press-hours are not a veto. Buy, or at least get the quote moving, when:
- No press passes Gate 1 or Gate 2. The mould needs more tonnage, tie-bar room or a different barrel than anything you own.
- The right-tonnage presses are genuinely full. After the mould moves and the cheap fixes, they still run booked jobs for most of their scheduled hours, and the queue stays.
- The customer requires a dedicated press, for example for a food-contact or medical part with its own validation. Read the customer's requirement; don't guess it.
- The job is firm and long. A one-year schedule can carry an EMI that a six-month trial order can't.
Indian manufacturers ran at 77.4% capacity utilisation in January–March 2026, per the RBI's 73rd OBICUS round released 5 August 2026 (RBI OBICUS). That is a national average, not a figure for your 350s; your own press log decides. The same logic applies in metal: see proving CNC capacity before buying another machine.
What cameras can and can't tell you here
An overhead camera on the press line can show what your planning sheet can't:
- Idle while scheduled, by cause: platens open with no operator nearby, no material at the hopper, a press waiting for the QC inspector.
- Mould change door to door: from the last good shot to the first approved part, including crane and trolley waits.
- Which mould ran on which press, and for how long, so a small mould on a big press shows up in the monthly hours.
It can't tell you:
- Clamp tonnage, shot size or barrel capacity. Those come from the mould drawing, the resin and the machine data sheet.
- Exact cycle time. Use the controller's cycle log.
- Part quality. Flash, short shots and sink marks need inspection or machine vision, not a ceiling camera. Our injection-moulding camera guide covers where cameras help on the line.
- Anything about a named worker. Count hours per press and per shift, never as an operator ranking. 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 (DPDP worker CCTV notice).
Where Mama fits
Mama reads the cameras a moulding unit already has, or ones added for the purpose, and every morning sends the owner a short plain-language note on where press-hours went the day before: running, mould change, or idle while scheduled, by tonnage class and shift. Mama watches presses, moulds and material flow, not individual workers. If a new mould job is waiting on a press decision, leave an email or phone in the form below and Mama will get back to you with a camera plan for measuring press-hours first.
FAQ
How do I know if my presses have room for a new mould? Take only the presses that can clamp the mould and put the shot at 25–65% of barrel capacity. Subtract planned stops, booked running hours, mould changes and idle time from calendar hours, and compare the remainder with the job's shots × cycle time plus mould changes.
How much tonnage does my mould need? Multiply the projected area of parts and runner by a tonnage factor. A common starting point is 3 tons per square inch, within a typical range of 2 to 10, per Plastics Technology (2017). Confirm with the resin supplier and the tool maker, and then reduce clamp force in trials rather than running at the press maximum.
What does a new 350-tonne injection moulding press cost in India? As of 17 Oct 2026, one Ahmedabad seller lists a 350-tonne servo press at ₹44 lakh and a 550-tonne at ₹58.82 lakh. Chiller, dryer, loader, foundation and installation come on top. Get at least two written quotations.
Can I run a small mould on a bigger press? Often yes, if the mould fits the platens and the shot stays above 25% of barrel capacity. But it ties up hours on a press that larger moulds need, and clamping at full tonnage can damage vents and parting lines. Check your big presses for small moulds before you buy another big press.