A pulp molding machine is a five- or six-figure capital purchase that travels thousands of kilometers before you ever see it run. By the time it reaches your factory, correcting a misaligned press frame, an undersized vacuum pump or a control cabinet wired for the wrong voltage is slow, expensive and entirely your problem. That is why serious buyers insist on a factory acceptance test (FAT) before shipment — a structured, witnessed run at the manufacturer's plant where the machine is checked against the contract, not against a promotional video.

This guide explains what a proper FAT covers, how to measure real output instead of trusting a nameplate, which defects buyers most often miss, and how to document findings so that open issues are closed before the container is loaded rather than after.

Why a Factory Acceptance Test Matters More Than a Video Tour

Suppliers routinely send short clips of a machine running. Those clips show the best case: fresh pulp, a warm mold, an operator who has run the same product for years. They do not show the machine at cold start, at the end of a shift, or with the fiber mix you actually intend to use.

A witnessed FAT answers three questions a video cannot. First, does the machine perform at the capacity and quality stated in the contract? Second, are the components the ones you paid for — motor brands, vacuum pump capacity, PLC model, frame thickness? Third, is the machine complete, including guards, spare molds, tooling and documentation?

Buyers who skip this step usually discover the gaps during installation, when the supplier's engineer is on site for a fixed number of days and every delay shortens the commissioning window. The cost of one inspection trip is almost always smaller than the cost of one unresolved defect discovered after arrival.

What to Agree Before the Test

The FAT only has value if its rules are fixed in the sales contract. Agree the following in writing at least two weeks before the scheduled date.

Test product and mold

Specify which product will be molded during the test — for example a 30-egg tray, a fruit tray or an industrial insert — and confirm that the mold used is the mold you are buying. Testing with a different mold proves nothing about your tooling.

Acceptance criteria

Write measurable numbers: output per hour, draw depth tolerance, wall thickness range, moisture content after drying, and an acceptable defect rate such as under two percent rejects over a continuous run. "Good quality" is not a criterion; a number is.

Duration and witness

Require a continuous run of at least four hours, not a ten-minute demonstration. State whether you or your third-party inspector will attend, and confirm that the supplier bears the cost of the test material.

Video backup

If travel is impossible, arrange a live video session with fixed camera positions and a checklist read aloud on camera, plus photographs of nameplates and serial numbers. A recorded walkthrough is weaker than attendance but far better than nothing.

Step-by-Step Inspection Checklist

Work through the machine system by system. Photograph everything and note serial numbers as you go.

Structure, frame and alignment

Check frame welds for porosity or unfinished seams, confirm the base is level, and verify that guide rods and columns show no scoring. Ask for the frame steel thickness with a caliper. Confirm that anchor points match the foundation drawing you received.

Forming station and vacuum system

Watch a full cycle: pulp fill, vacuum suction, mold lift, transfer. Confirm vacuum holds steady under load and that the pump is the specified model, not a smaller substitute. Inspect the mold face for uniform mesh tension and look for pulp buildup that signals poor washing or an undersized vacuum line.

Hot press and drying

Verify that platen temperature reaches set point across the full surface using a contact thermometer or thermal camera at several points. Watch a press cycle for even pressure and check that the hydraulic or pneumatic circuit holds pressure without dropping.

Electrical cabinet and controls

Open the cabinet. Look for labeled terminals, correctly sized breakers, a proper grounding bar and no loose wire ends. Confirm the PLC, touchscreen and inverter brands against the contract. Check that the machine is wired for your voltage and frequency — 380V/50Hz, 440V/60Hz and 415V/50Hz are all common export configurations, and a mismatch means a transformer or motor replacement on arrival.

Safety devices

Test every interlock physically: open the guard and confirm the machine stops, press the emergency stop at each station and confirm it latches, and check that the hot press cannot close with a hand in the mold zone. Safety is the one category where "we will fix it later" is not acceptable.

How to Measure Real Capacity

Nameplate capacity is a theoretical figure based on cycle time with no interruptions. Measure it properly: run continuously, record the start and end time, count only good parts, and calculate output per hour from that data.

Then measure the cycle yourself with a stopwatch, three times in a row, and compare it with the figure in the contract. A machine rated at 1,500 pieces per hour that cycles every 3.2 seconds is not going to deliver 1,500 good pieces once you subtract mold cleaning, pulp changes and rejected parts.

Also weigh output per shift, not per hour. Energy use, pulp preparation time and operator breaks all belong in the real number. Our guide to sizing production capacity explains how to translate hourly figures into a realistic annual plan.

Defects Buyers Commonly Miss

Several problems survive a casual walkthrough because they only appear under specific conditions.

Wet spots and uneven wall thickness. Check parts from the first cycle and the last cycle of the run; differences reveal vacuum or slurry consistency problems.

Mold wear on new tooling. Look closely at the mesh and the sealing edge. A mold that shows compression marks before shipment will fail early in production.

Missing or substituted components. Compare every major component against the packing list and the contract. Substitutions are rarely accidental and always cheaper for the supplier.

Incomplete documentation.