{"id":2112,"date":"2026-08-21T10:54:10","date_gmt":"2026-08-21T02:54:10","guid":{"rendered":"https:\/\/yfnsktd.com\/?post_type=news&p=2112"},"modified":"2026-08-21T18:04:21","modified_gmt":"2026-08-21T10:04:21","slug":"poly-v-pulleys-ph-to-pm-profiles-materials-and-sizing","status":"publish","type":"news","link":"https:\/\/yfnsktd.com\/tr\/news\/poly-v-pulleys-ph-to-pm-profiles-materials-and-sizing\/","title":{"rendered":"Poly-V Kasnaklar\u0131: PH \u2013 PM Profilleri, Malzemeler ve Boyutland\u0131rma"},"content":{"rendered":"

KTD Engineering Team | Application Engineering & DFM Team | Published: August 21, 2026<\/p>\n

Poly-V pulleys<\/a> carry 40\u00b0 V-grooves at a rib pitch fixed by profile: PH 1.6 mm, PJ 2.34 mm, PK 3.56 mm, PL 4.70 mm, PM 9.40 mm. ISO 9982 and DIN 7867 standardize that geometry, so sections never interchange. Match profile, rib count and effective diameter, and belts fit across suppliers.<\/p>\n

The reference tables that engineers actually need for this decision sit mostly in European catalogue PDFs and behind standards paywalls. What follows is the pulley-side geometry in one place, with the parts of ISO 9982 that change how you read a supplier’s dimension sheet.<\/p>\n

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Poly-V Kasnaklar\u0131: PH \u2013 PM Profilleri, Malzemeler ve Boyutland\u0131rma<\/p><\/div>\n

Profile Reference: PH Through PM<\/h2>\n\n\n\n\n\n\n\n\n
Profile<\/td>\nRib pitch<\/td>\nYiv a\u00e7\u0131s\u0131<\/td>\nTypical duty<\/td>\nPublished max belt speed<\/td>\n<\/tr>\n
PH<\/td>\n1.60 mm<\/td>\n40\u00b0<\/td>\nAppliance and light equipment drives; uncommon in industrial plant<\/td>\n\u2014<\/td>\n<\/tr>\n
PJ<\/td>\n2.34 mm<\/td>\n40\u00b0<\/td>\nFractional-horsepower equipment, compact machinery<\/td>\n\u2248 60 m\/s<\/td>\n<\/tr>\n
PK<\/td>\n3.56 mm<\/td>\n40\u00b0<\/td>\nAutomotive accessory drives; industrial crossover use<\/td>\n\u2248 50 m\/s<\/td>\n<\/tr>\n
PL<\/td>\n4.70 mm<\/td>\n40\u00b0<\/td>\nMid-range industrial drives<\/td>\n\u2248 40 m\/s<\/td>\n<\/tr>\n
PM<\/td>\n9.40 mm<\/td>\n40\u00b0<\/td>\nHigh-horsepower machinery, heavy industrial drives<\/td>\n\u2248 30 m\/s<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

Rib pitch, groove dimensions and minimum diameters all follow DIN 7867 and ISO 9982, which is what allows belts and sheaves to interchange between brands. The speed figures are published section maxima and drop as the section grows; treat them as a screening limit, not a design target.<\/p>\n

PH deserves a note. It exists in the standard and it is real, but the smaller PH section is rarely encountered in industrial plants. If a drive specification calls for PH, confirm the belt is actually available in the length you need before committing the pulley geometry.<\/p>\n

PK sits in two standards at once. ISO 9982 covers PH through PM for industrial applications, while ISO 9981:2020 addresses PK specifically for automotive accessory drives \u2014 and states that PK belt profile dimensions and tolerances are identical in both International Standards. A PK pulley cut to either document is dimensionally the same part. The difference lives in the surrounding application requirements, not the groove.<\/p>\n

What ISO 9982 Specifies, and What It Leaves to You<\/h2>\n

The current edition is ISO 9982:2021, third edition, published September 2021 by the International Organization for Standardization under technical committee ISO\/TC 41\/SC 1 Its scope is the principal dimensional characteristics of V-ribbed pulley groove profiles together with the corresponding endless belts, for PH, PJ, PK, PL and PM profiles in general industrial applications, excluding elastic belts.<\/p>\n

Three things inside it change how a dimension sheet should be read.<\/p>\n

Effective diameter is not pitch diameter, and neither is outside diameter. The true pitch diameter of a V-ribbed pulley is slightly larger than the effective diameter. Effective diameter is the working figure for speed ratio. Outside diameter is what you measure with a caliper. Suppliers publish different ones, and a ratio calculated from an outside diameter is wrong by an amount that grows as the pulley gets smaller.<\/p>\n

Groove surface finish is specified, not left to machining preference. The 1998 edition called for pulley groove surface roughness below Ra 3.2 \u03bcm Rough grooves accelerate rib wear because a V-ribbed belt transmits power by friction across the flanks, and the flank is where the belt lives.<\/p>\n

Minimum effective diameter is tabulated per profile. ISO 9982 gives minimum recommended effective diameters for V-ribbed pulleys in a dedicated table. The specific values belong to the standard document, and any supplier quoting below a section’s minimum should be asked why. Going under it forces rib compression the belt was not designed for, and the failure shows up as rib cracking rather than as slip.<\/p>\n

What the standard does not give you is power rating. Rating comes from the belt manufacturer, against your rib count, effective diameter, wrap angle and service factor. A pulley conforming to ISO 9982 tells you the belt will fit. It does not tell you the drive will carry the load.<\/p>\n

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Poly-V Kasnaklar\u0131: PH \u2013 PM Profilleri, Malzemeler ve Boyutland\u0131rma<\/p><\/div>\n

Reading and Writing a Poly-V Designation<\/h2>\n

A Poly-V pulley<\/a> is fully described by four items:<\/p>\n

    \n
  1. Profile letter\u2014 PH, PJ, PK, PL or PM.<\/li>\n
  2. Number of ribs\u2014 the count of grooves, which must match the belt’s rib count exactly.<\/li>\n
  3. Effective diameterin millimetres.<\/li>\n
  4. Mounting\u2014 taper bush size, or finished bore with tolerance class and keyway.<\/li>\n<\/ol>\n

    A drive quoted as “PK, 6 ribs, 112 mm effective, taper bush 1610” is buildable. “PK 112” is not, because it omits both the rib count and how the pulley attaches to a shaft.<\/p>\n

    Rib count is where field substitutions go wrong most often. A 6-rib belt on an 8-rib pulley runs, and it runs badly: the belt tracks toward one end, the loaded ribs carry proportionally more tension than the design assumed, and the two unused grooves collect debris. Maintenance teams accept this because the machine keeps turning. Belt life falls by a margin nobody logs.<\/p>\n

    Material Selection<\/h2>\n\n\n\n\n\n\n\n\n\n
    Malzeme<\/td>\nWhere it belongs<\/td>\nTrade-off<\/td>\n<\/tr>\n
    HT150 gray cast iron<\/td>\nGeneral industrial drives, standard taper-bush pulleys<\/td>\nMass; brittle under impact loading<\/td>\n<\/tr>\n
    HT200 gray cast iron<\/td>\nHigher-load industrial drives, better wear resistance<\/td>\nHigher cost than HT150; same brittleness class<\/td>\n<\/tr>\n
    6061-T6 aluminum<\/td>\nHigh-speed and high-acceleration drives where inertia dominates<\/td>\nSofter groove flanks; wears faster in abrasive air<\/td>\n<\/tr>\n
    Karbonlu \u00e7elik<\/td>\nHigh torque, welded or fabricated assemblies<\/td>\nCorrosion protection required; heaviest option<\/td>\n<\/tr>\n
    Stainless steel (custom)<\/td>\nWashdown, chemical exposure, food and pharma equipment<\/td>\nMachining cost; quoted as custom<\/td>\n<\/tr>\n
    Engineering plastics (custom)<\/td>\nCorrosion resistance, low noise, light duty<\/td>\nDimensional movement with temperature and humidity<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

    KTD’s stated operating range for its Poly-V line is \u221230 \u00b0C to +90 \u00b0C. That figure is a system limit rather than a metal limit, because it is the belt compound that governs the ceiling in most drives. Cast iron does not care about 90 \u00b0C. The rubber running in its grooves does.<\/p>\n

    Cast iron remains the default for industrial Poly-V<\/a> because the profile is usually applied where a V-belt drive is being replaced for power density, and those drives are not inertia-limited. Aluminum earns its place on the driven side of high-acceleration machinery, where the rotating mass of a cast-iron pulley costs more in acceleration torque than it returns in wear life.<\/p>\n

    Taper-Lock Versus Solid Bore<\/h2>\n\n\n\n\n\n\n\n\n\n\n
     <\/td>\nKonik bur\u00e7<\/td>\nSolid \/ finished bore<\/td>\n<\/tr>\n
    Shaft diameter change<\/td>\nSwap the bush, keep the pulley<\/td>\nNew pulley required<\/td>\n<\/tr>\n
    Stock strategy<\/td>\nOne pulley covers a bore range<\/td>\nOne SKU per bore size<\/td>\n<\/tr>\n
    Concentricity<\/td>\nDepends on bush seating and correct torque<\/td>\nMachined directly, one interface fewer<\/td>\n<\/tr>\n
    Axial space<\/td>\nBush adds length beyond the hub<\/td>\nCompact<\/td>\n<\/tr>\n
    Removal<\/td>\nDesigned for repeated removal<\/td>\nPuller, and often heat<\/td>\n<\/tr>\n
    Small diameters<\/td>\nConstrained; bush needs hub wall<\/td>\nAvailable down to small pitch diameters<\/td>\n<\/tr>\n
    Torque transfer<\/td>\nFriction across the tapered interface, plus key<\/td>\nKeyway, set screw, or interference fit<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

    Taper bushes dominate industrial Poly-V for a maintenance reason rather than an engineering one: the same pulley fits several shaft diameters, and a plant carrying twelve machines carries fewer spares. What it costs is axial length and one more interface that can be assembled wrong. A bush torqued below specification slips under load and polishes the taper, which then never grips properly even after re-torquing.<\/p>\n

    Solid bore wins where axial space is tight, where diameters are small enough that a bush leaves no hub wall, and where concentricity matters to the drive. KTD supplies both configurations, along with heavy-duty and steel variants for higher-torque service.<\/p>\n

    Compared with the catalogue-style listings that dominate this search, which present bore options as a selection field, the choice is a maintenance-strategy decision made once per machine platform rather than once per pulley.<\/p>\n

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    Poly-V Kasnaklar\u0131: PH \u2013 PM Profilleri, Malzemeler ve Boyutland\u0131rma<\/p><\/div>\n

    Y\u00fczey \u0130\u015fleme<\/h2>\n

    Four options apply to the Poly-V line:<\/p>\n