Avoid Costly Buying Mistakes

Whether purchasing a new machine or a reconditioned press in Indian industrial markets, never release payment based solely on a fresh coat of paint. Conduct this rigorous 10-point technical due diligence on the factory floor.

The 10-Point Technical Inspection Checklist

1. Magnetic Particle Crack Testing (MPI): Inspect the sharp radius corners of the C-frame throat and crankshaft fillet shoulders to verify zero micro-stress fractures.
2. Bed-to-Ram Parallelism: Mount a dial test indicator on the ram face. Sweep all four corners of the bed bolster plate. Maximum runout must not exceed $0.02 ext{ mm per }300 ext{ mm}$.
3. Bushing Clearance Under Load: Position a hydraulic jack between bed and slide. Pump to $5 ext{ tons}$ pressure while observing the dial gauge on the connecting rod bushing. Play must remain under $0.05 ext{ mm}$.
4. Flywheel Dynamic Balance: Run the flywheel uncoupled from the clutch at full motor speed. Place a coin vertically on the frame—it should stand upright without toppling from harmonic vibration.
5. Gib Slideway Scrape Marks: Check that bronze gib faces show authentic hand-flaked oil-pocket patterns, rather than unhardened rough milling lines.
6. Clutch Air Consumption: For pneumatic presses, charge the clutch, shut off the compressor, and verify line pressure drops less than $0.1 ext{ bar}$ over 10 minutes.
7. Crankshaft Material Certification: Demand chemical metallurgical test certificates confirming forged alloy steel (EN-8 / EN-9 / 42CrMo4) rather than unhardened mild steel round bar.
8. Dual-Hand Safety Anti-Tie Down: Confirm that taping or holding one start button prevents machine tripping.
9. Emergency Stop Response Angle: Trigger an E-stop at $90^circ$ mid-stroke; the ram must halt within $15^circ$ of actuation.
10. Continuous Dry-Run Temperature Check: Run the press idle for 60 minutes. Check all main bearings with an infrared thermometer; temperatures should not exceed $15^circ ext{C}$ above ambient room temperature.