Quality Control

Quality Control

We are an ISO/TS 16949 certified company showing our determination and insistence on quality and continuous progression.

Our QC dept. takes charge of the production quality. We check every step of the processes such as the inspection of forging material, daily process inspection, and final product inspection. Besides, the MSA and SPC analysis also show that our process stability and measurement system are reliable. We have faith to deliver excellent products to our customers.

  • Main Inspection InstrumentsOpen or Close
    Measurement Scope Tolerance Instrument Capability
    Bore Diameter ±0.005mm Bore Gauge (Sunnen) 0.001mm
    Bore to Bore Distance ±0.05mm Micro-Hite Gauge (TESA) 0.001mm
    Rod Thickness ±0.05mm Micrometer (Mitutoyo) 0.001mm
    Hardness HRC 25~45
    HRC 59~63
    Hardness Testing Machine (Mitutoyo) 1 HRC
    Roundness / Cylindricity 0.003mm Round Tester (Mitutoyo) 0.01μm
    Roughness Under Ra 0.2μm Roughness Meter (Mitutoyo) 0.01μm
    Parallelism 0.05/100 Indicator (Mitutoyo) 0.01mm
    Ring Gauge Correction ±1μm Universal Length Measuring Instrument (Helios) 0.1μm
    Rod Profile ±0.30mm Video Measuring System (ARCS) 0.5μm
    Bore Gauge
    Micro-Hite Gauge
    Hardness Testing Machine
    Round Tester
    Roughness Meter
    Parallelism Measurement
    Ring Gauge Correction
    Video Measuring System
  • Measurement Systems Analysis (MSA)Open or Close

    Following shows the MSA analysis of our bore gauge. Results show that all the MSA requirements including stability, bias, linearity, repeatability, and reproducibility are qualified. Of course, other measurement systems are also qualified to ensure our measurements are reliable.

    Repeatability: %E.V. = 8.77%
    Reproducibility: %A.V. = 4.92%
    Gage R&R: %GR&R = 10.06%
  • Statistical Process Control (SPC)Open or Close

    Following shows our SPC results of big-end bore diameter. The Cpk of big-end bore diameter is 2.57 (which should be larger than 1.33) showing our excellent process control on the con-rods production.

    Big-end Bore Diameter (51 pieces):
    X-R Control Chart
    Specification Limit
    Control Limit
    Cpk=2.57 (>1.33)
    Measurement Distribution
  • Weight Measurement: All Machined Surface TypeOpen or Close

    We developed all machined surface type rods to precisely control the weight of rods. Excellent weight control can assure excellent dynamic performance at high RPM.

    Weight Amount
    472-474g 12
    474-476g 85
    476-478g 102
    478-480g 21
    Total 220
  • Fracturing-Splitting TechniqueOpen or Close

    Our fracturing-splitting technique have been developed for more than ten years. The irregular cutting surface results in an excellent assembling repeatability. Following Chart shows the reassembling result of our product. Results show that the bore diameter and roundness is almost the same after reassembling.

    Test Model: 688 (Yamaha 85HP)
    No. Bore Diameter
    (After Honing)
    Bore Roundness
    (After Honing)
    Bore Diameter
    (After Reassembling)
    Bore Roundness
    (After Reassembling)
    1 39.023 0.002 39.025 0.002
    2 39.023 0.002 39.024 0.002
    3 39.025 0.002 39.026 0.002
    4 39.023 0.002 39.024 0.002
    5 39.025 0.002 39.027 0.003
    6 39.022 0.002 39.024 0.002
    7 39.022 0.002 39.023 0.002
    8 39.021 0.003 39.023 0.003
    9 39.024 0.002 39.024 0.003
    10 39.023 0.002 39.024 0.003