Technical articles by topic
Standards interpretation, selection and measurement methods, organized into the six topics below. Spec sheets, test reports, SDS and white papers are in the technical library below.
About this library
These technical documents are compiled by the JIAHON Engineering Department from actual line assessments, implementation reports and standards interpretation, not catalog copy. Each one is written as a web page you can read directly, every standard cited links to its official source, and each ends with related articles and supplied items on this site.
Every document links to a full PDF in Chinese and English. If the spec or assessment you need is not listed, contact the Engineering Department directly.
SMT processes and international standards
Interpretation of soldering, printing and inspection standards, and implementation assessments.
- J-STD-001 electronic assembly standard explained: Class 1/2/3 and soldering requirements: Class 1/2/3 classification and scope, the 0.8 mm minimum lead protrusion, fillet height criteria for chip components, BTC thermal pad voiding, and what revision J adds on hardware installation and X-ray void images.
- IPC-7526 stencil and misprinted board cleaning handbook explained: Chemistries for seven types of contaminants, nine cleaning methods, the 110°F temperature limit, ultrasonic 40 kHz and ≤10 W/L parameters, and heavy-metal limits for wastewater.
- J-STD-001 vs IPC-A-610: process standard and inspection standard compared: J-STD-001 covers how to build; IPC-A-610 covers whether the result is acceptable. A seven-point comparison, Class 1/2/3 judgment principles, the four certification levels CIS/CSE/CIT/MIT, and the two standards’ simultaneous release on April 8, 2024.
- SPI implementation assessment: pFMEA shows solder paste volume is high risk: Using pFMEA RPN to prioritize SPI: solder paste volume scores RPN 448. Includes CKD VP5200 measurements on 34,243 pads, a 150-second cycle time, 30 consecutive repeatability runs and payback analysis.
- PCBA inline adhesive inspection assessment: blue glue height and white glue area AOI: Hands-on evaluation of 3D structured light for blue glue height and AOI for white glue area: C2100 series FOV and accuracy, measured repeatability of 0.09 mm, and why static capture beats on-conveyor measurement.
- Flip-chip underfill in volume production: plasma pretreatment, void control and release criteria: Four underfill types and the capillary flow formula, measured O₂ plasma pretreatment data, three causes of voids and their countermeasures, and release criteria for fillet height and C-SAM.
- SMT stencil cleaning and compatible squeegee blades: a case with five measurements: Five before-and-after measurements and how to read them, and the scope of IPC-7527, 7525 and 7526 versus the often misquoted IPC-9850.
- Reflow oven condensers and flux capture: causes of profile drift, cleaning intervals and safety: Where flux goes inside the oven and six consequences of failed capture, setting cleaning intervals by throughput rather than the calendar, and three early warning signs in the reflow profile.
- How to read SMT stencil wiper roll specs: fiber blend, GSM, spunlace and core diameter: How to read fiber blend, basis weight, manufacturing method and core inner diameter, and six specs to confirm before purchasing.
- Solder paste printing defects and stencil cleanliness: five defects classified by cause: Defect terms clarified, a cause-based diagnosis table, and using whether the defect location is fixed to tell aperture clogging from residue on the stencil underside.
- The core SMT line process: key parameters and inspection roles in printing, placement and reflow: Key parameters for printing, placement and reflow and how SPI, AOI and AXI divide the work, with four commonly misread points in equipment specs and component codes.
Cleaning and process chemicals
Solvent selection, regulatory compliance and supply chain changes.
- HFE (hydrofluoroether) technical white paper: properties, immersion cooling and selection after 3M’s exit: HFE has an ODP of 0, a GWP of 55 to 320 and dielectric strength above 35 kV,, unlike highly toxic hydrofluoric acid. Covers four fluid types, five industries, immersion cooling at PUE 1.02 to 1.05, and choices after 3M exited PFAS.
- AI-500CIP continuous cleaning machine prototype white paper: reversible conveying and inline CIP: How reversible conveying removes cleaning dead zones under BGAs and in SiP gaps, the removal-rate gains from 2 to 8 MPa high-pressure pulsed jets, and inline CIP with ionic contamination verification (IPC-TM-650 2.3.25).
- JH64 stencil and flux cleaner: RoHS, halogen-free and PFOA/PFOS reports and SDS highlights: Scope and method detection limits (MDL) of two third-party reports (CTI 2025, SGS 2023), plus SDS composition, the 12°C flash point and on-site protection requirements.
- ThreeBond 2706 degreaser SDS highlights: GHS classification, composition and site controls: What GHS carcinogenicity 1A and reproductive toxicity 1A mean in practice, why the n-hexane content is easy to misread, and the ventilation, PPE and storage conditions to confirm before use.
- HY-8601 industrial antistatic liquid: 125°C flash point, composition and line use: Available data such as the 125°C flash point and no detected halogens, and five fields where this SDS falls short for hazard communication.
- Masking tape MSDS line by line: seven CAS components, toluene content and seven data gaps: CAS numbers and functions of seven components, what toluene (108-88-3) in the solvent field means, and seven fields in this safety data sheet that are inconsistent or blank.
- HFE implementation validation and EHS compliance: validation plan, acceptance criteria and RACI: Deliverables for four implementation phases, a five-item validation matrix, three traps in reading acceptance criteria, plus EHS engineering controls, audit document packages and RACI roles.
- Choosing a stencil cleaning machine: electric vs pneumatic, recommendations for three line types and maintenance: A seven-point electric vs pneumatic comparison, selection advice by line type, pre- and post-shift SOPs and a preventive maintenance plan.
Cleanroom and ESD protection
Contamination control at entry, consumable traceability and grounding verification.
- Choosing mesh caps, shoe covers and sticky mats: selection, donning order and an eight-week trial: The three-item set for gowning-area contamination control, with applications across EMS/SMT, biotech, laboratories, pharma and food, cleanrooms, pet shops and paint booths.
- The devil is in the details: what unbranded consumables don’t tell you: Unbranded consumables carry no brand marking: spec drift, untraceable batches and unclear responsibility are the three engineering breaks behind line problems with no root cause. How the JIAHON brand makes responsibility concrete.
- Do ground monitor alarms need regular calibration? Condition monitoring vs precision metrology: A ground monitor alarm is a condition-monitoring device, not a precision instrument; it judges continuity, so it needs functional testing rather than calibration. How it differs from precision instruments and how to check it on site.
- JH-038A grounding system monitor alarm spec sheet: parameters, wiring and threshold settings: Technical parameters for the adjustable 0 to 500 Ω monitoring range and open-circuit alarm, wiring, threshold settings, and the difference between ground path resistance and surface-to-ground resistance.
- SL-031A personal ESD tester manual: pass limits, installation and RS232 output: Upper and lower pass limits for wrist straps and footwear, why too-low resistance also fails, red-right blue-left installation, and the six-byte RS232 data format.
- How to measure antistatic values properly: surface resistance steps and common mistakes (LDPE bag test): Why the insulator reference cannot be skipped, why humidity must be recorded, the difference between Ω/sq and Ω, and five common measuring mistakes on site.
- PU palm-coated glove EN 388 test report: the 3131X code digit by digit: What each digit of EN 388 code 3131X means, why X does not mean a fail, and which tasks this glove does and does not suit.
- Antistatic PVC mesh curtain test report: four tests and installation acceptance points: What each of the four tests measures, how a one-to-two order-of-magnitude difference between front and back affects installation direction, and why hanging it up does not make it effective.
- How to read cleanroom wiper specs: 3002/3008/4009 differences, edge sealing, LPC and NVR: What LPC, NVR and absorbency mean and how they are measured, and what to ask the supplier when two models have identical specs.
- ESD lift swivel chair spec sheet: six base styles, height ranges and grounding: Height range table for six base styles, how to read the 10⁵ to 10⁹ Ω resistance value, three common breaks in the grounding path and key acceptance measurements.
- Ionizing fans and static meters: a case with six measurements and ion balance interpretation: How ionization and grounding divide the work, six before-and-after measurements, how to read ion balance and discharge time, and maintenance and calibration points.
- ESD workstation integration: four measurements for mats, wrist straps, heel straps and cleanroom benches: Specs and measured data for four items, the personal-safety role of the 1 MΩ resistor in wrist straps, and how Class 10000 maps to ISO Class 6.
- ESD finger cots and cleanroom wipers: four measurements on personnel contact contamination: Four before-and-after measurements, the unit difference between surface resistivity and surface resistance, what laser edge sealing does, and why finger cots cannot replace personnel grounding.
- Choosing cleanroom garments, shoes and ESD slippers: garment limits, person-footwear-floor measurement and acceptance: Which standard each type of personnel gear follows, the limits, the acceptance documents required, and four common mistakes in citing standards.
Measurement and industrial safety
Traceability of measurement references, and design principles for hazardous material storage.
- Why aren’t explosion-proof storage cabinets fully sealed? Structural design and vapor buildup: Without forced exhaust, a sealed cabinet lets solvent vapor build up to the lower explosive limit, where friction or static discharge on opening can ignite it; door gap tolerances provide passive pressure relief.
- Choosing a reflow profiler: Wickon, KIC and DATAPAQ specs compared: The three manufacturers’ published specs side by side, and when resolution, sampling rate, internal temperature rating and thermal barrier size actually matter.
- Hydrogen leak detection tape spec sheet and test report: 1% sensitivity, color change time and reading: The 65 μm PI substrate structure, 1% hydrogen sensitivity and color change time, and which document governs when the spec sheet and batch report acceptance ranges disagree.
- WICKON Q24 reflow profiler spec sheet: 24 channels, ±0.5°C, Insight software: Full specs, accessories and Insight software functions for the 24-channel model, and how to choose channel count and thermal barrier for your oven.
- WICKON Q12 reflow profiler spec sheet: 12 channels and thermocouple placement: Body shape differences between the 12- and 24-channel models, and the real effect of thermocouple placement and attachment on results.
- Reflow profiler thermal barrier rating table: maximum exposure times for WICKON and KIC configurations: Maximum exposure times and dimensions of eleven thermal barrier configurations at 150 to 400°C, and how to select by dwell time.
- White-light structured light thickness and deformation measurement: carrier warpage, board warp and paste thickness: Measuring principle and light source selection, three verification measurements, and the commonly misunderstood boundary with high-temperature package warpage standards.
- Where thermocouple wire errors come from: IEC 60584-1 tolerance classes and the whole measurement chain: Tolerance class conversion table for type K thermocouples, five error sources across the measurement chain, and how to spot silent degradation at junctions and connections.
Equipment, parts and materials
Equipment manuals, industrial material selection and paths for discontinued parts.
- RT-7000/7700 automatic tape cutter manual: controls and measured cut-length accuracy: Operating manual and controls for the RT-7000/7700, plus JIAHON Technical Quality Department measurements: 30 cuts each at 3, 4 and 5 cm of 20 mm gold-finger tape (Kapton/polyimide), 90 in total, with a standard deviation of 0.05 to 0.06.
- Imported parts cost too much and take too long, and discontinued parts leave you stuck: Imported spares are expensive with lead times of 8 to 16 weeks, and after discontinuation there is nothing to buy. How reverse engineering finds the root cause and redesigns an improved part across material, machining and surface treatment to lower total cost of ownership.
- Polyurethane flame-retardant filter foam UL 94 HF-1 burn test report: criteria and delivery notes: HF-1 and HF-2 differ in whether drips ignite the cotton pad, and two limits: the report used only room-temperature conditioning, and it is not UL certification.
- Fiber optic cleaning pen specs and use: 2.5 mm vs 1.25 mm, and why end-face cleaning matters: How to tell 2.5 mm from 1.25 mm, the standard inspect-clean-inspect process, and why alcohol wipes are not a substitute.
- Industrial drum filter 30T for fish ponds: specs, installation, controller settings and troubleshooting: Full specs and controller setup steps, and why a smaller outlet pipe makes the machine flush nonstop.
- Part reverse engineering and redesign: 3D scanning, material analysis and surface treatment: The actual reverse engineering workflow, three dimensions that can be changed, and two specs that are easy to misread: hardness scales and DLC classification.
- SMT line setup checklist for consumables and spares: key specs, acceptance methods and safety stock days: Specs, acceptance and safety stock days for about forty consumables and spares across ten process areas, usable directly as a purchasing checklist draft.
Packaging and in-plant logistics
Selecting returnable packaging and calculating how many sets you need.
- WIP returnable packaging analysis: selection for short-distance transport and set calculation: Packaging for 1 km short-distance transport: five-point comparison of disposable vs reusable, ergonomic limits (120 cm reach height, 6 per box), set calculation over eight dwell points, and the practical limits of the EVA option.
- Black EVA foam SGS RoHS test report: full data, limits and interpretation: Full data and MDL for ten restricted substances, and three easily overlooked points: ND does not mean zero, the cadmium limit is especially low, and the simple acceptance decision rule.
- Wooden pallets and crate bases for server cabinets: E classes, G-value targets and pallet selection: E-1 to E-4 classes and G-value targets, why dynamic load should be three to five times the cabinet weight, and five checkpoints when reviewing drawings.
- Choosing ESD foam: inherently conductive vs surface-treated, and reading four specs: How the two types differ and how to tell them apart, practical reading of four specs, and design principles for pairing with totes and thermoformed trays.
- Choosing semiconductor totes and ESD trays: three layers of protection, JEDEC tray sizes and automation docking: How to specify the three layers of protection separately, the registration basis for tray outlines, and how to ask about ‘automation compatible’.
MRO purchasing methods
Supplier structure, hidden costs and the practical logic of consolidated purchasing.
- Let down by a new supplier again? Breaking the purchasing vicious circle: The cost of onboarding new suppliers: evaluation, quotation credibility, coordination friction and the hidden costs of factory consumables purchasing.
- Stop comparing prices blindly: less is more in MRO purchasing: Consolidating MRO suppliers to lower total purchasing cost: hidden costs, transaction cost theory, total cost of ownership and optimizing supplier count.
- How one-stop MRO reduces stock-out risk and MOQ problems: The hidden costs not shown on a quotation are what really eat the purchasing budget. How consolidated MRO addresses stock-out risk, MOQ hurdles and scattered responsibility so fragmented purchasing becomes stable supply.
- Backup plan for an overseas SMT line: failure risks and degraded-mode operation for 13 auxiliary equipment items: Failure risks, backup approaches and three backup types for each of 13 auxiliary equipment items, including two practical limits of dry cabinets and solder paste refrigerators.