![\"\"](\"http:\/\/yfnsktd.com\/wp-content\/uploads\/2026\/08\/Gear-1.webp\")
\u00d6zel Di\u015fli \u00dcreticisi Nas\u0131l Se\u00e7ilir: OEM Kontrol Listesi<\/p><\/div>\n
Why supplier capability pages are a poor comparison tool<\/h2>\n
Search for a custom gear supplier and page one is almost entirely self-description. Equipment lists, material lists, industries served. Two suppliers can publish near-identical pages while producing gears that differ by several accuracy grades and behave very differently after 2,000 hours in a gearbox.<\/p>\n
The gap is not marketing dishonesty. It is that the things separating gear manufacturers are difficult to display on a web page: distortion control after carburizing, whether the grinder is actually used on production parts or only on samples, whether inspection happens on a gear-specific<\/a> instrument or a general-purpose CMM with a generic probing routine.<\/p>\n This checklist is organised around questions that force those things into the open. Most of them are answerable in one email. If they are not, that itself is information.<\/p>\n A supplier quoting “AGMA 10” or “ISO grade 7” has given you a number without a coordinate system. Two things need to be pinned down before the number means anything.<\/p>\n First, the numbering direction. Under the older AGMA quality-number convention, a higher number indicates a more accurate gear. Under ISO 1328 and the AGMA accuracy grading that aligns with it, the scale runs the other way, and a lower number is the tighter one. A quoted “grade 10” therefore describes a fairly precise gear under one system and a fairly loose one under the other. The American Gear Manufacturers<\/a> Association, now operating as the Motion + Power Manufacturers Alliance, maintains the gear accuracy and inspection standards on the US side and participates in ISO gearing standardisation, so both systems remain in active use and both will appear in supplier correspondence.<\/p>\n Second, which parameters the grade covers. An accuracy grade is not a single tolerance. It is a bundle covering profile deviation, helix deviation, pitch deviation and runout, and a gear can meet the stated grade on three of those and miss on the fourth. Ask which parameters were measured and which were assumed.<\/p>\n What to send back:\u00a0“Please confirm the standard and edition your quality grade references, and list the individual deviation parameters your inspection report will cover.”<\/p>\n A supplier who works to gear standards routinely answers this in a sentence. A supplier who has taken the number from a machine-tool brochure usually does not.<\/p>\n Over-specification is common and expensive. Grinding a gear to a grade tighter than the application requires can add significantly to unit cost and lead time for no measurable benefit in the assembly. A general-purpose industrial drive running at moderate speed with a modest transmission-error budget is often well served by a hobbed and heat-treated gear. Precision grinding earns its cost when noise, positioning accuracy or high pitch-line velocity are genuinely in the specification.<\/p>\n Before you set the grade, define what the gear must actually achieve: peak and continuous torque, operating speed, expected duty cycle, acceptable noise level, and required service interval. Then let the supplier propose a grade against those numbers. If they cannot connect a grade to your operating conditions, they are quoting a process, not engineering a part.<\/p>\n Heat treatment is where custom gear quality most often diverges from the drawing. Carburizing raises surface hardness and case depth, and it also moves the part. A gear ground to a tight grade before carburizing does not stay at that grade afterwards.<\/p>\n The questions worth asking:<\/p>\n That last one is the most revealing. A supplier who has been making carburized gears for years has seen how a given tooth geometry moves and has adjusted the pre-grind stock allowance accordingly. A supplier who has not will discover it on your parts.<\/p>\n \u00d6zel Di\u015fli \u00dcreticisi Nas\u0131l Se\u00e7ilir: OEM Kontrol Listesi<\/p><\/div>\n Material selection constrains heat treatment. Case-hardening steels such as SCM415 and 20CrMnTi are chosen for carburizing. Medium-carbon steel such as S45C or 1045 suits induction hardening or through-hardening. Stainless grades including SUS304 are selected for corrosion resistance and behave differently under heat treatment than alloy steels. Engineering plastics such as MC Nylon and POM are not heat treated at all and are specified for light-load, low-noise or non-lubricated applications.<\/p>\n If a supplier accepts your material callout without comment when the material and the specified heat treatment are mismatched, that is a signal about how much engineering review actually happens before the part goes into production.<\/p>\n Ask for a sample inspection report before you place an order, ideally for a part of similar size and type. Look for four things:<\/p>\n The related question is what happens between the first article and the thousandth part. First Article Inspection is a snapshot. Ask what the in-process sampling plan looks like for the production run, and what triggers a re-inspection.<\/p>\n A quality management system certified to ISO 9001:2015 \u2014 the internationally recognised quality management system standard published by the International Organization for Standardization \u2014 gives you a documented framework for process control and corrective action. It is not, on its own, evidence of gear accuracy. Treat it as a floor rather than an answer.<\/p>\n There is a meaningful difference between a supplier who quotes from your drawing and one who reviews it first.<\/p>\n A design-for-manufacturability review before quoting typically raises things like: a tolerance that is achievable but expensive relative to its function, a fillet or undercut that forces a slower operation, a bore tolerance that could be relaxed without affecting fit, a material callout with a long procurement lead time, a hub geometry that could be simplified without changing the interface.<\/p>\n Ask directly: does DFM feedback come before the quote or after the purchase order? The answer changes the economics of the project. Feedback after the PO means either a change order or a part built exactly as drawn, including the parts of the drawing that were costing you money without buying anything.<\/p>\n Also confirm which file formats are accepted and what happens if you only have a legacy 2D drawing or a physical sample. Reverse engineering from a worn sample is a genuine capability and not every supplier offers it.<\/p>\n Custom gear buyers rarely need one quantity. They need a prototype run, then a validation batch, then production, and they would prefer not to change suppliers between those stages because each change resets the learning about distortion and tooling.<\/p>\n The column that matters most is the last row. Every technical question routed through an intermediary loses detail and gains days. On a custom gear programme with three or four rounds of drawing clarification, that compounds.<\/p>\n Ask for the minimum order quantity and the practical upper limit per run, and ask whether tooling built for the prototype carries over to production or is re-made.<\/p>\n Set against that checklist, here is what KTD publishes for its industrial precision gear<\/a> line, so the criteria above can be applied rather than described.<\/p>\n Gear types produced:\u00a0spur, helical, internal, straight bevel, spiral bevel, worm gears and gear racks.<\/p>\n Materials:\u00a0S45C \/ 1045 steel, SCM415, 20CrMnTi, SUS304 stainless steel, cast iron, MC Nylon and POM.<\/p>\n Heat treatment:\u00a0induction hardening, carburizing and nitriding.<\/p>\n Finishing operations:\u00a0precision grinding, honing, black oxide and zinc plating.<\/p>\nQuestion 1: Which standard is that quality grade written against?<\/h2>\n
The grade you specify and the grade you need<\/h3>\n
Question 2: How is heat treatment controlled, and by whom?<\/h2>\n
\n
![\"\"](\"http:\/\/yfnsktd.com\/wp-content\/uploads\/2026\/08\/Gear-2.webp\")
Material and heat-treatment pairing<\/h3>\n
Question 3: What does the inspection report actually contain?<\/h2>\n
\n
Question 4: How are drawings handled before quoting?<\/h2>\n
Question 5: Does the volume range fit the way you actually buy?<\/h2>\n
\n\n
\n Evaluation dimension<\/td>\n Local job shop<\/td>\n Dedicated gear manufacturer<\/td>\n Distributor \/ trading intermediary<\/td>\n<\/tr>\n \n Typical minimum order<\/td>\n 1\u201310 pieces<\/td>\n 20 pieces upward<\/td>\n Varies; often catalogue-driven<\/td>\n<\/tr>\n \n Volume ceiling<\/td>\n Limited by machine hours<\/td>\n Thousands to 10,000+ per run<\/td>\n Depends on the factory behind them<\/td>\n<\/tr>\n \n Gear-specific equipment<\/td>\n Often general machining only<\/td>\n Hobbing, grinding, gear inspection<\/td>\n Not applicable<\/td>\n<\/tr>\n \n Who performs DFM review<\/td>\n Machinist judgement<\/td>\n Application engineering function<\/td>\n Passed through, often with delay<\/td>\n<\/tr>\n \n Distortion history on similar parts<\/td>\n S\u0131n\u0131rl\u0131<\/td>\n Accumulated across programmes<\/td>\n Not held directly<\/td>\n<\/tr>\n \n Response time on technical queries<\/td>\n Fast<\/td>\n Fast where engineering is in-house<\/td>\n Two-step, through the intermediary<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n KTD gear manufacturing specifications<\/h2>\n
![\"\"](\"http:\/\/yfnsktd.com\/wp-content\/uploads\/2026\/08\/Gear-3.webp\")