How to inspect and accept the purchased used injection molding machine
Phase 1: Document and Static Inspection (at the equipment's current location)
Document Verification:
Technical Documents: Request the Operation Manual, Maintenance Manual, Electrical Schematics, and Hydraulic Schematics. These are the foundation for future repairs.
Historical Records: Review past maintenance records to understand the replacement history of wearing parts (such as screws, barrels, and seals).
Spare Parts List: Verify that all included spare parts (such as oil filters, fuses, and tools) are complete.
Static (Power-Off) Inspection:
Structural Integrity: Inspect the four main tie rods for cracks, strain, or weld repairs. Inspect the movable and fixed platens and hinges for visible cracks or deformation.
Hydraulic System:
Oil Tank: Open the tank cap and check the hydraulic oil condition. The oil should be clear or light yellow. If it is milky white (water content) or dark black (oxidation), it indicates poor maintenance.
Leaks: Carefully inspect the oil pump, cylinder, valve block, and all pipe joints for signs of oil leaks.
Electrical System:
Electrical Box: Open the electrical box and inspect key components such as the mainboard, driver, and power supply for signs of burning or corrosion, and check the wiring harness for neatness and signs of rat gnawing.
Controller: Test the buttons and screen for sensitivity and integrity.
Core Components - Screw and Barrel:
Radial Clearance: Manually shake the screw head to check the radial clearance between it and the barrel. Excessive clearance (usually exceeding 3-4mm) indicates severe wear, poor plasticizing, and the need for expensive repairs.
Inner Wall Wear: Shine a flashlight on the inner wall of the barrel to check for deep grooves or scratches.
Phase Two: Dynamic and Performance Acceptance (Must be tested with power on and material present)
This is the core of the acceptance process for used injection molding machines and must be tested using general-purpose plastics such as PP or PS.
No-Load Operation:
Motion: Test all movements, including mold opening and closing, ejection, and shot table movement, to observe whether they are smooth and stable, and whether there are any hitches or unusual noises.
Noise: Start the oil pump motor and listen for any unusual squealing or banging sounds. A normal sound should be a steady rumble.
Heating and Temperature Control System:
Start the heater coils and observe the temperature rise rate. Use a portable thermometer to verify that the displayed values on each temperature control gauge are consistent with the actual values (the error should be within ±5°C).
Injection and Plasticizing Performance:
Injection: Perform the injection motion and observe whether the injection is linear and smooth, and whether there are any pressure fluctuations or creep.
Screw Rotation: Perform pre-plasticization, listen for any unusual friction noises during screw rotation, and observe whether the screw retracts evenly.
Holding Pressure: Test the holding pressure function and check whether the pressure gauge pointer is stable.
Clamping Force and System Pressure Test:
Clamping Force: Place "pressure test paper" or a soft lead strip in the mold and clamp the mold at the rated clamping force. Remove and inspect the indentation to determine whether the four tie rods are evenly loaded and whether the mold plates are parallel.
System Pressure: Test the equipment to the rated system pressure to check whether it can be reached and maintained stably. Also, observe the hydraulic system for leaks.
Phase 3: Final Confirmation and Document Handover
Trial Production: If conditions permit, conduct a small-batch trial using your own molds and materials. This is the ultimate test to verify the machine's ability to consistently produce qualified products.
Final Document Handover: After acceptance, ensure all agreed documents and spare parts are packaged with the equipment.
Signed Equipment Acceptance Report: Detailed documentation of the acceptance process and test data is included. After confirmation by both parties, the report is signed and stamped as proof of contract completion.
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Boring Machine Cost Guide: What Affects the Price of Industrial Equipment?Two boring machines intended for similar repair work canreceive very different quotations because the price reflects more than the machine’s basic size. Machine type, working range, drive power, accuracy requirements, tooling and included automation all affect the final configuration. To compare a boring machine price accurately, compare the scope of supply and the job requirements, not just the headline figure. What drives the quotation? Price factor Why it affects cost Details to specify Machine type and setup Portable systems and larger stationary equipment have different structures and intended applications. Equipment type, work location and setup constraints Bore size and machining range Required diameter, bar length and travel determine the working envelope and compatible components. Minimum and maximum bore diameter, machining length and access Power and duty Drive requirements depend on the material, cutting conditions and expected workload. Workpiece material, typical jobs and operating frequency Accuracy and tooling Accuracy requirements and the tooling package influence component selection and what must be supplied. Required results, cutters, mounts and other tooling needs Automation and customization Controls, optional functions and non-standard configurations add scope to the build. Required automation, special interfaces and quantity Configuration matters more than a bare price A lower-priced machine may have a narrower machining range, fewer included tools or less automation. A higher quotation may include a broader configuration or options that are unnecessary for a particular job. Neither price alone establishes suitability. For a portable boring machine price comparison, check that the quoted setup can reach the bore, fit the available work area and perform the required operation. Accuracy should also be described in terms of the work to be done. Share the required result and relevant workpiece details so the supplier can quote a configuration against the application. Avoid comparing quotations that assume different tooling, accessories, automation or customization. Prepare information for a useful quote For a meaningful boring machine cost estimate, provide the bore diameter range, machining length, material, workpiece or equipment details, site access constraints and expected operating frequency. List required tooling, accuracy expectations, automation and any special mounting or interface requirements. Include the purchase quantity and identify which accessories should be included. Ask suppliers to show the proposed configuration and included items in the quotation. This makes differences easier to trace and helps prevent a low initial figure from omitting components needed for the intended work. Submit the same job information to each supplier when comparing offers. Frequently asked questions Why is one boring machine much cheaper than another? The machines may differ in type, working range, power, included tooling, accuracy-related configuration, automation or customization. Compare the quoted scope against the same application before judging the difference. What information is needed to quote a boring machine? Provide the required bore diameters and machining length, material, workpiece and site constraints, expected use, accuracy needs, tooling and automation requirements, customization details and order quantity. These details help suppliers quote a configuration suited to the job.
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Used Automatic Lathe Machine for Sale WorldwideUsed automatic lathe machines provide a practical route to high-volume turning capacity without the lead time and capital cost of new equipment. For worldwide buyers, condition verification and supplier capability determine whether a low purchase price becomes a reliable production asset. Used Automatic Lathe Machine for Sale Worldwide What Buyers Should Assess A well-maintained cam-operated or CNC automatic lathe can retain stable repeatability for years when spindle bearings, guideways, collets, lubrication, and control components are within specification. Typical remaining service life is 5-12 years for a properly rebuilt machine, but heavily worn feed systems, obsolete controls, and unavailable parts create material selection risk. Machine type Typical work Used price range Main risk Cam automatic lathe Small pins, screws, fittings US$3,000-15,000 Cam and clutch wear Single-spindle CNC lathe Precision shafts, bushings US$8,000-35,000 Control and servo age Swiss-type CNC lathe Medical and electronics parts US$18,000-80,000 Guide bushing accuracy Inspection Before Shipment Checkpoint Acceptance focus Spindle Measure runout, noise, heat, and speed stability Axes and slides Check backlash, repeatability, way damage, and lubrication Tooling system Confirm collet, turret, feeder, and change-part availability Trial cutting Verify diameter, surface finish, cycle time, and scrap rate Electrical system Test alarms, drives, safety devices, and documentation Request a cold-start video, spindle runout report, sample-part test, machine serial number, and packing photographs. Accuracy claims should be supported by measured results, not appearance or repainting. China Supplier Value Established China-based suppliers combine broad used-machine sourcing with competitive refurbishment costs and export packing experience. Prefer suppliers able to provide inspection records, relevant quality certification, export documents, remote commissioning support, and stocked wear parts such as collets, belts, seals, sensors, relays, and hydraulic components. Cost item Direct as-is purchase Inspected Chinese supplier Initial price Lower Moderate Condition evidence Often limited Test data and video Export support Buyer-managed Crating and documentation After-sales response Uncertain Parts and technical support FAQ Can a used automatic lathe hold tight tolerances? Yes, after measured verification, alignment, and trial cutting; condition matters more than machine age. What accuracy should be checked? Check spindle runout, axis backlash, repeat positioning, workpiece diameter variation, and surface finish. Are old controls a concern? Yes. Confirm backup availability, drive condition, electrical drawings, and an upgrade path before purchase. Should buyers choose rebuilt equipment? Choose rebuilding when it includes documented replacement of wear components and a witnessed test, not cosmetic painting alone. Which spare parts should be ordered initially? Order consumable seals, belts, collets, sensors, contactors, filters, and model-specific tooling where available. Can a Chinese supplier arrange worldwide delivery? Experienced exporters can arrange seaworthy packing, shipping documents, and remote installation guidance. Choose a reliable Chinese supplier that can prove machine condition, support export delivery, and quote the right configuration for your current parts. Request a current quotation with inspection data before ordering.
