A buyer in Kobe, Japan in energy equipment has a cast stainless pump housing where the machined bore lip, split flange gasket face and drain port need deburring while the as-cast texture stays as specified. SurfacePolish supplies finishing machines, media and compounds across borders, and a free sample trial sends representative parts to Xiamen and returns them with an observation record and a proposed media, compound and cycle direction. This brief is written for a buyer in Kobe working on energy equipment; it describes equipment, media and a scoped sample review, not a local polishing service.
Which edges on this part are functional, such as gasket lands, seat bands, stem guides, metering lands and thread entries, and which only need to be free of a sharp edge?
Which material families and heat-treatment states share the equipment, and what separation is needed to avoid ferrous or graphite carry-over onto stainless parts?
What must the part be clean of, and what method and limit does the buyer use to verify cleanliness before assembly, welding, coating or a leak test?
Deburring specifications fail more often on the incoming condition than on the finishing parameters. Two machining suppliers can deliver the same part number with visibly different burr height, edge sharpness, tool marks and trapped chips, because feed, tool wear and coolant strategy differ. A cycle that clears one supplier's burr may leave the other's root attached. Before writing any requirement, record what arrives: where the burrs sit, how tall they are, how sharp the edges are, the roughness at named points and the mass of the part. Keep one as-received reject in the sample set so the route is tested against the worst credible input rather than an average one. When the requirement is written, state the starting condition it assumes.
Compound delivered at the wrong concentration or flow makes the same media behave like a different charge. Too little and the abrasive cut becomes dry and marking increases; too much and cutting slows while foam and carry-over rise. Flow rate matters as much as dose, because it is the flow that carries fines away from the part and keeps the working zone consistent across a long cycle. Water quality belongs in the same discussion: hardness, pH and dissolved solids in the make-up water shift the compound's behaviour, and a plant that changes its water source can change its results without touching a machine setting. Where the fluid is recirculated, filtration and turnover decide how much swarf and broken media stay in suspension and how often the bath is dumped.
| Media | Best fit | Watch out for |
|---|---|---|
| Heavy-cut ceramic, angle-cut triangles in a coarse size class | Removing a substantial or thick burr root from open external edges, flange corners, cast bosses and large tapped entries on steel and stainless parts | Cuts controlled edges and gasket lands as readily as burrs, leaves a coarse surface, and lodges in slots whose width approaches the media section |
| Dry media, corn cob granules with a polishing compound | Final dry polish, light edge blending and drying after a wet stage on small parts and fittings | Almost no cutting action, absorbs compound and contaminates quickly, and must be kept separate per material family to avoid carry-over |
| Magnetic pin or needle charge | Reaching small internal intersections, radial holes and thread entries on small precision parts such as spools, sleeves and drilled fittings | Limited by part size and shape, pins must be retrieved and inspected for breakage, and the result depends heavily on fixture and field design |
| Dry media, walnut shell with an abrasive or polishing compound | Light dry deburring, deflashing, drying and low-residue finishing of small parts and of features where a wet bath is difficult to remove | Low cutting energy so it cannot remove a substantial burr root, produces dust needing extraction, and consumption is high |
Internal intersections are a different problem from external surface refinement, and no amount of extra energy in a bowl fixes them. A cross-drilling meeting a main bore creates a burr on the inside wall that external media rarely reaches. Access routes include a small media size class that can enter the passage, magnetic finishing where a pin or needle charge is driven into the feature on small parts, or a targeted mechanical method outside mass finishing. Each has a boundary: a size class small enough to enter a passage is also small enough to lodge in it, magnetic pins are limited by part size and by retrieval, and blind features with no exit cannot be flushed clean. Decide per feature which access route is credible, and how the result will be seen.
| Machine route | Where it fits | What it will not do |
|---|---|---|
| Barrel finishing machine and rotary barrel tumbler | Gentle, low-impingement deburring of small, fragile or precision parts and mixed fitting batches where edge protection matters more than speed | Long cycles, no visibility while the barrel runs, and internal features can collect media and compound that must be retrieved at unload |
| Grinding finishing machine | Heavier stock removal and thick burr roots on robust parts where clearing material in a shorter cycle matters more than the surface result | Aggressive edge rounding and a coarser surface, so it fits lapped seats, thin sections and tight edge bands poorly |
| Tub vibrator | Long parts such as manifold rails, shafts, long housings and stacked plate sets that cannot tumble in a bowl, with support or rotation along their length | Lower energy per unit area so heavy burrs take longer, and the tub needs floor space plus a defined part support method |
| Magnetic finishing machine | Small precision parts with internal intersections, radial holes and thread entries that a bulk charge cannot reach | Limited by part size and material, pins must be retrieved and checked, and it does not level or refine large flat surfaces |
Contamination in this process is mostly invisible at the machine and is discovered downstream. Three forms matter on energy-equipment parts. Media fragments and abrasive fines can embed in soft surfaces or in a machined groove and later appear as particles in a fluid system. Material carryover happens when carbon steel fines or cast-iron graphite from an earlier batch stay in the charge, the machine, the rinse tank or the drying cloth and transfer to stainless parts. Compound residue and its reaction products can sit in a gasket groove, a thread or a blind hole and interfere with welding, passivation or a coating step. Control is separation and cleaning discipline, verified with a wipe or tape lift, magnification, and a flush residue check.
| Failure mode | Likely cause | How to catch it |
|---|---|---|
| Ferrous specking, rust staining or graphite smearing on stainless parts after a shared run | Carbon steel or cast iron fines carried over in the charge, machine, rinse tank or drying cloth, or a purge that was too short between material families | Compare against a retained reference part, inspect suspect areas at magnification, examine the charge and rinse for embedded ferrous fines, and review the changeover record against the batch history |
| Tenacious compound film or reaction residue left in a gasket groove, thread or blind hole | A film-forming or silicate-bearing compound, insufficient rinse volume or temperature, or drying the part before it is genuinely clean | Wipe a defined area with solvent against a clean reference, check for a continuous water film on a rinsed sample, and inspect recessed features at magnification before packing |
| Burr still present on an internal cross-drilling intersection after finishing | No credible access route for the charge, a medium too large to enter the passage, or a cycle too short for the intersection to see enough contact | Borescope the intersection at the agreed angle on sample parts, section one representative part to expose the wall, and compare against the recorded as-received condition |
| Media lodged in a cross-drilling, blind tapped hole, keyway, groove or internal passage | Size class chosen against an average feature rather than the smallest one, media fractured into smaller pieces during the cycle, or a secondary burr that closed part of the opening | Borescope agreed passages at a fixed angle, pin gauge every tapped hole, count the charge in and out where practical, flush through a filter and inspect the residue, and compare part mass before and after |
Kobe's manufacturing is concentrated in food, transport equipment and general machinery. The city's 2020 Census of Manufacture report counts 1,394 establishments with four or more employees, 67,951 workers and 3,421.1 billion yen of manufactured goods shipments, with value added up 3.3 per cent. It states that food manufacturing and metal products together account for about a quarter of all establishments, and that food, transport equipment and general machinery together account for just over half of employment, with Hyogo ward especially strong in transport equipment and Nishi ward in production machinery and metal products. The city also publishes an economic census and industrial statistics series, and the port has been the city's trade gateway since it opened to foreign trade in 1868.
The nearest part of that base to this brief is marine: Kobe City records that the port, opened to foreign trade in 1868, developed as an international trade port that continually installed the latest facilities, and that the opening of Kobe Airport in 2006 completed a sea-air-land transport system.
Kobe's three largest manufacturing employers by industry are food, transport equipment and general machinery, so the surface requirement splits between hygienic, cleanable finishes for food equipment and dimensional, burr-controlled finishes for transport and general machinery parts. General machinery and metal products are concentrated in Nishi ward, where small firms supplying machined components need a finish specification that travels with the drawing rather than a verbal agreement.
A Kobe buyer should separate the two cases before choosing a process: transport and general machinery parts where edge and burr limits govern, and food-equipment parts where cleanability and surface condition govern, because the same media and compound choice will not serve both.
Freight context: Port of Kobe (神戸港), open to foreign trade since 1868, Kobe Airport (神戸空港), opened in 2006. Kobe City records that after the 1995 Hanshin-Awaji earthquake the port's facilities were restored within two years, and that the 2006 opening of Kobe Airport established a combined sea, air and land transport system. Customs clearance in the Kobe area is handled by Kobe Regional Customs, one of Japan Customs' regional offices.
The national standards body is the Japanese Industrial Standards Committee (JISC), which states that JIS covers industrial and mineral products, data, services and management systems under the Industrial Standardization Act. Its technical divisions include mechanical engineering, ferrous materials and metallurgy, nonferrous materials and metallurgy, ceramics, medical equipment and safety appliances, and aircraft and aviation, which are the divisions a finishing or deburring requirement is normally read against. Product certification runs through the JIS Mark Certification Scheme, operated by accredited certification bodies compliant with ISO/IEC 17065; as of March 2019 there were 24 JIS-accredited bodies, three of them outside Japan, with about 8,700 certifications issued, and the scheme explicitly covers foreign manufacturers, processors and exporters.
Documentation and technical communication are Japanese-language in practice: JISC states that the documents submitted for JIS certification-body accreditation must be written in Japanese, and drawings, inspection sheets and purchase specifications from Japanese buyers are normally issued in Japanese. Import declarations are filed in triplicate and importers commonly use licensed customs brokers, so the commercial invoice, packing list and origin documents must be complete and consistent with the declared commodity code. As general industry practice in Japan, industrial buyers qualify a supplier on documentation, quality-management evidence and a defined inspection standard before volume orders, and expect a named Japanese-speaking contact for technical and commercial follow-up.
SurfacePolish supplies from Xiamen, China. The buyer's own destination rules, conformity marking, tariff classification and documentation responsibilities stay with the buyer; confirm them against the authorities named above before ordering.
Write acceptance around measurement locations, not around a single number for the part. Mass finishing produces a gradient: an edge or a corner receives far more work than a flat face, and a recessed or shielded area receives less. A roughness value quoted without a location, a parameter, a cut-off length and an evaluation direction cannot be reproduced by anyone else and cannot be defended later. For each controlled surface, name the feature, the position on it, the parameter, the cut-off, the evaluation length and the direction relative to the machining lay. Reference the surface texture convention the buyer already uses, such as the ISO 4287 and ISO 4288 families or ASME B46.1, rather than inventing a house definition. Agree the instrument before the first part is measured.
The value of a sample trial comes from the range of parts sent, not from the quantity. A box of identical nominal parts tests one geometry and one burr condition; it cannot show how the proposed route behaves on the tightest passage, the thinnest wall or the hardest material in the family. Send a small set chosen to cover the extremes: the part with the smallest internal opening, the part with the longest unsupported section, the part with the most protected edge, one part in the hardest heat-treatment state the family sees, and one as-received reject that already fails. Label every part so its identity survives the trip, and send enough pieces that some can be sectioned or measured destructively.
Size the charge well below the smallest opening it could enter, and treat every passage as a retrieval point rather than assuming it stays clear. List the tightest hole, slot, thread and cross-drilling first, then choose a size class against that geometry instead of the average part. Screen the working charge, because fractured media produces smaller pieces that defeat the original sizing. Plan detection: a borescope at an agreed angle, a pin gauge in every tapped hole, a count of the charge in and out where practical, a flush collected through a filter, and a part mass check. For Kobe buyers preparing a trial, include the smallest passage.
Protect it deliberately rather than relying on a gentle setting. Options include masking or plugging the face, fixturing the part so the land is held out of the mass, orienting the part so the land sees less contact, or choosing a media shape and size that blends rather than digs. Each has a cost: a masked face keeps its as-machined condition and can show a boundary line, a fixture shields the area behind it, and fixturing reduces how many parts fit in a load. Mark the land on the drawing, give it a maximum edge radius, and agree how it will be checked. Test the arrangement on the real part.
The visible lip is the part of the burr that is easy to see and easy to blend flat. The root is the material still connected to the parent surface underneath it, and it is the part that can break free later as a particle, especially in a flowing gas or hydraulic circuit. A light refinement pass can roll the lip over and make the edge look finished while leaving the root attached. Deburring is therefore judged on whether the root has been removed, which usually means removing a small amount of parent material at the edge rather than only wiping the surface. Agree how that judgement will be made.
Use Kobe, Japan as the destination on the enquiry and state whether the deliverable is equipment, media and compound, a representative sample review or a line concept. A destination does not imply local stock, a local service point or a local delivery time.
Kobe buyers reference JIS, maintained by the Japanese Industrial Standards Committee, whose mechanical engineering and ferrous materials divisions cover the city's machinery and transport-equipment output, with the JIS Mark scheme available for third-party product certification. For food-equipment work the additional reference is the customer's hygiene and cleanability requirement, which is specified on the drawing rather than by a general finishing standard.
Sources were retrieved on 2026-09-29 and describe the local industrial and trade context only. They do not evidence any SurfacePolish project, shipment, installation or service in Kobe.
The buyer wants the machining burrs at the bore lip, split flange gasket face and drain port removed without polishing away the as-cast texture the specification protects.
Send the material, dimensions, approximate weight, batch quantity, the incoming condition and photographs of the difficult features. Mark which features must not be contacted by media and state how the result will be inspected. This form carries source reference PSEO-0858; quote it if you prefer an additional manual reference.
Open the SurfacePolish enquiry form Email a prepared enquiry
No price, lead time, certification or result is promised here. Confirm whether a sample trial is available for the specific part and what the trial can and cannot show.
Page PSEO-0858 · revised 2026-09-29 · cross-border equipment, media and scoped sample review. City context is sourced and cited above.
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