Most plant managers we work with do not need new injection molding machines. They need their existing machines to change molds faster. A retrofit hydraulic quick mold change system delivers that result for around 4 to 8% of the cost of buying a new machine, and the downtime to install it is measured in days, not weeks.
The retrofit path is well-established. We have completed installations on machines from 1998 to 2024, across Haitian, Engel, KraussMaffei, Arburg, Yizumi, JSW, and Borche brands. This guide explains the technical assessment, the installation sequence, the cost structure, and the ROI calculation in the format we share with customers in Malaysia, Indonesia, Vietnam, Thailand, and Europe.
If you are evaluating whether your machines are retrofittable, the answer is almost always yes. The right questions are how much, how long, and what the production-day impact will be.
What “Retrofit” Means in QMC Context
A hydraulic quick mold change retrofit replaces the manual mold mounting on an existing injection molding machine with hydraulic clamping. The machine itself is not modified structurally. The platens stay in place. The original control system stays in place. What gets added is a hydraulic power unit, the clamping cylinders, the routing hoses, an operator HMI, and a single PLC signal back to the machine control.
This is different from a machine rebuild, which replaces the hydraulics of the machine itself. A QMC retrofit is bolt-on. The most invasive modification is drilling and tapping the platen for the clamp mounting bolts. On most machines, the platen already has T-slots or threaded holes, so even drilling can often be avoided.
The result is an existing injection molding machine that performs mold change in 5 to 15 minutes instead of 90 to 240 minutes, with the rest of the machine unchanged.
Step 1 — Machine Survey Before Quotation
Every retrofit begins with a survey. We send a one-page form before quoting any job. The information required is:
- Machine brand, model, and year
- Clamping tonnage and platen dimensions
- Platen drilling pattern (T-slot pitch or threaded hole locations and sizes)
- Existing HPU capacity and pressure on the machine
- Available 3-phase power supply and free space near the machine
- Mold inventory: weights, flange thicknesses, and clamping slot positions
- Available production downtime window for installation
This data feeds three decisions: what clamp model to specify, whether the existing machine HPU can supply the QMC, and where to physically locate the new HPU if a separate unit is required.
Step 2 — Compatibility Check by Machine Brand
Every major injection molding machine brand has a known retrofit profile. The differences matter for budgeting.
Haitian (MA, JU, VE, IA series) — Standard 24 mm T-slot pattern on platens. Direct mount with standard clamp body. Existing HPU is usually sufficient for clamp supply if free flow capacity exceeds 4 L/min. Retrofit completes in 2 days.
Engel (e-mac, victory, duo) — European T-slot pattern, sometimes with proprietary spacing. Adapter plate may be required. Engel machines often have free hydraulic ports labeled “Auxiliary 1” and “Auxiliary 2” that can supply QMC pressure. Retrofit completes in 2 to 3 days.
KraussMaffei (CX, PX, GX) — Threaded mounting holes in M16 or M20. Direct mounting. KraussMaffei’s central HPU is typically over-sized and can supply QMC with no additional pump. Retrofit completes in 2 days.
Arburg (Allrounder series) — Compact platens with limited drill locations. Adapter plate is standard. Arburg HPU pressure is 200 bar matched. Retrofit completes in 2 to 3 days.
Yizumi, Borche, JSW, Toshiba — Each has known patterns we have catalogued from previous installations. Most are direct mount or use one of three standard adapter plates.
Step 3 — Machine HPU vs Separate HPU
The two options are: tap the existing machine HPU for clamp pressure, or install a dedicated HPU next to the machine. The decision depends on the machine HPU’s spare capacity.
Three factors limit tapping the machine HPU: pressure compatibility (QMC needs 200 bar, some older machines run 140 or 160 bar), control isolation (requires pressure isolation valve and separate PLC interlock), and service continuity (if machine HPU is down, QMC is also offline).
Around 60% of customers choose a dedicated HPU. The price difference is 2,500 to 4,500 USD depending on size, which is recovered within the first year through the cleaner system separation.
Step 4 — Installation Sequence and Downtime
A standard 4-clamp retrofit on a 500-ton machine:
Day 1 morning (4 hours) — Machine shutdown, mold removal, platen cleaning, drilling and tapping if required, adapter plate installation if required.
Day 1 afternoon (4 hours) — Clamp body mounting, hose routing, HPU placement and power connection, oil filling, pressure test. Cylinders dry-cycled without mold present.
Day 2 morning (4 hours) — PLC interlock wiring, HMI mounting and configuration, machine safety interlock test, dummy mold load and clamp engagement test, alignment verification.
Day 2 afternoon (4 hours) — Real mold load, clamp force verification with calibrated pressure gauge, first production trial. Operator orientation training (4 hours total over the 2 days).
For most installations, the machine is back in production at the end of Day 2. Total downtime is 16 working hours.
Step 5 — Commissioning and Verification
The verification includes static clamp force measurement using a hydraulic load cell at each clamp position, pressure decay test over 30 minutes with cycle interlock, PLC fail-safe test by simulating a pressure drop and confirming machine cycle stop within 200 ms, operator HMI walkthrough, and emergency stop verification.
The customer signs off after observing one complete mold change at production speed. The first mold change is done by KINGHOU personnel. The second is done by the customer operator with KINGHOU observing. From the third change onward, the operator runs the system independently.
Step 6 — ROI Calculation Format
The retrofit business case has three inputs.
Production hours recovered per year: (Manual change time − Hydraulic change time) × Mold changes per year × Number of machines.
For a typical 500-ton machine doing 6 changes per week with manual change at 3 hours and hydraulic at 12 minutes: (180 − 12) min × 6 × 52 = 52,416 minutes = 873.6 hours per year per machine.
Revenue impact: Production hours × Average parts per hour × Margin per part.
For a packaging plant in Thailand running thin-wall buckets: 873.6 × 1,200 parts/hour × 0.08 USD margin = 83,866 USD per year per machine.
Cost recovery: Retrofit cost / Annual revenue impact = Payback period. For a 17,500 USD retrofit: 17,500 / 83,866 = 0.21 years = approximately 11 weeks.
Payback periods between 8 and 26 weeks are typical across our SEA and European customer base.
Common Retrofit Mistakes
Mistake 1 — Ordering before survey. A supplier quotes from a brochure without seeing the platen. The clamps arrive and do not fit.
Mistake 2 — Skipping the PLC interlock. Some low-cost retrofits omit the pressure feedback signal to the machine PLC. The system works but the machine does not know if a clamp loses pressure during injection.
Mistake 3 — Undersized HPU. A 1.5 kW HPU specified for a machine that runs in a tropical plant cannot maintain pressure when oil temperature exceeds 50 °C.
Mistake 4 — Single supplier for the full plant without survey of each machine. Different machine vintages have different platen patterns.
When Retrofit Is Not the Right Choice
Three situations call for a different decision. If the machine is over 25 years old and the platens show fatigue cracks, the retrofit is uneconomic. If the machine clamp tonnage is undersized for the work the plant is taking on, retrofitting the mold change does not solve the production constraint. If the machine is going to be sold or relocated within 18 months, the retrofit payback may not complete before the move.
Frequently Asked Questions
What is the typical cost of retrofitting a hydraulic QMC?
For a 250 to 500 ton machine, 6,500 to 12,000 USD. For 500 to 1,000 ton machines, 12,000 to 22,000 USD. For 1,000 to 1,600 ton machines, 20,000 to 35,000 USD. These prices include hardware, installation, training, and 24 months of remote support.
Can a hydraulic QMC be retrofitted to a 20-year-old machine?
Yes, in most cases. Machines from 2000 onward are routinely retrofitted. The platen condition is the critical question, not the machine age.
How long does the machine have to be out of production?
Standard retrofit is 2 working days. For plants that cannot afford 2 days, we have completed installations in 12 to 14 hours using pre-fabricated mounting.
Does the retrofit void the original machine warranty?
For machines still under original warranty, the answer depends on the manufacturer. Haitian, Yizumi, and Borche accept QMC retrofits with no warranty impact. Engel, KraussMaffei, and Arburg sometimes require pre-approval of the retrofit design.
Can the QMC be moved to a different machine later?
Yes. The clamp bodies and HPU are reusable. Moving the system costs 30 to 50% of the original installation cost.
What kind of training do operators need after retrofit?
4 hours total. The HMI is single-screen with mold selection, clamp engage, clamp release, and emergency stop. Most operators are comfortable after 2 mold changes.
How is the hydraulic QMC different from a magnetic mold change retrofit?
Hydraulic uses mechanical clamping cylinders. Magnetic uses electromagnetic platens. Hydraulic is cheaper for low to medium mold change frequency and works on any machine.
What ongoing maintenance does a retrofitted system require?
Annual oil filter change, biennial seal inspection, 5 to 7 year seal replacement. Annual maintenance cost is under 1% of system purchase price.
Next Steps
Send us your machine list with model and year. We respond with the survey form and a target installation window within 1 working day. The survey itself is free. The first written quotation is delivered 5 working days after the completed survey is returned.
Contact Cherry through the hydraulic quick mold change system page or directly on WhatsApp at +86 187 0625 8221. For multi-machine projects, we recommend a video site visit before quotation.
Related KINGHOU resources: hydraulic quick mold change system; hydraulic mold clamps; hydraulic vs magnetic quick mold change comparison.
