Sprockets with QD Bushings American Standard

Sprockets with QD Bushings

QD (Quick Disconnect) sprockets use the American quick-disconnect taper bushing system — the dominant shaft-mounting method for heavy ANSI chain drives in North American industry. The QD bush is a split-taper insert with a flange, accepting a straight-bore cylindrical through-bore that is split longitudinally to allow radial compression on the shaft. The taper angle is steeper than the European taper lock, and the QD bush is retained by cap screws through the bushing flange into the sprocket hub rather than into the bushing itself.

Κατηγορία:
Επικοινωνήστε μαζί μας τώρα

#35 – #120

Εύρος μεγέθους αλυσίδας

JA – J

QD Bush Series

Seconds

Shaft Removal Time

ANSI B29.1

Πρότυπο

QD Bushing Sprockets — American Standard

The defining advantage of QD over setscrew bore for heavy American drives is the self-locking taper grip combined with the self-releasing split bore — loosening the cap screws and reversing them into the removal holes ejects the bush and sprocket from the shaft in one action, without any puller, hammer or heat. For drives on grain elevator head shafts, conveyor tail pulleys, aggregate plant drives or any other high-maintenance position where the sprocket must be pulled every season or every major service, QD mounting is the industry standard in North America.

The QD bush series covers shaft sizes from 5/8" (JA bush) to 4-7/16" (M bush). All Korea Ever-Power QD sprockets are bored to the standard QD taper profile and accept bushes from any QD-compliant supplier. The sprocket hub is the same C45 carbon steel as the standard bore range, with ANSI B29.1 induction-hardened tooth profile. Simplex, duplex and triplex available for all chain sizes in the range. Browse the πλήρης κατηγορία γραναζιών for all mounting types.

 

 Sprockets with QD Bushings

⚡ QD vs Split Taper vs Taper Lock

Three taper bushing systems are in common use — each with a different hub geometry:

  • QD (Quick Disconnect) — American; steeper taper, largest bore range, cap screws through flange into hub; widest industry adoption in USA/Canada
  • Split Taper (B-066) — American; fully split bush, self-ejecting without tapped removal holes
  • Taper Lock (1008–5050) — European/metric; partial split, metric cap screws, metric bore; ISO standard

These three systems are NOT interchangeable — the taper angles and hub bore geometries differ.

QD Bush Size Guide — Shaft Range, Bolt Size & Typical Chain Application

QD bushes are designated by letter pairs (JA, SH, SK, SF, E, F, J, M). The sprocket is ordered with the hub bored to match the QD profile for the required bush letter code. Specify the bush code when ordering — the hub taper bore is fixed to that bush series at manufacture.

Sprockets with QD Bushings Dimension

QD Bush Min Bore Max Bore Bolt Size Τυπική εφαρμογή
JA 5/8″ 1-3/8″ 5/16-18 UNC #35, #40 light conveyors
SH ½″ 1-3/8″ 5/16-18 UNC #40, #50 medium conveyors
SK ½″ 1-7/8″ 3/8-16 UNC #40–#60 medium-heavy drives
SF ½″ 2-7/16″ ½-13 UNC #60, #80 heavy industrial
E ¾″ 2-15/16″ 5/8-11 UNC #80, #100 heavy plant
F 1″ 3-7/16″ 5/8-11 UNC #100, #120 very heavy drives
J 1-3/8″ 3-15/16″ ¾-10 UNC #100, #120 large sprockets
M 2″ 4-7/16″ 1-8 UNC #120 maximum shaft drives

QD bushes sold separately. The QD bush code must match the sprocket hub bore exactly — there are no interchangeable bush codes across the same shaft diameter. Always confirm both the bush code and bore diameter when ordering.

QD Sprocket Specifications — #35 through #100

All hubs to QD taper profile. ANSI B29.1 tooth form. C45 steel. QD bush sold separately. Simplex (S), duplex (D), triplex (T) available.

Chain Pitch Z Range QD Bush Series Strand de at Z=17 (in)
#35 ⅜″ 15 – 84 JA, SH S, D, T 2.23
#40 ½″ 13 – 84 JA, SH, SK S, D, T 2.98
#50 ⅝″ 12 – 84 SK, SF S, D, T 3.72
#60 ¾″ 11 – 84 SK, SF, E S, D, T 4.46
#80 1″ 9 – 84 SF, E, F S, D, T 5.80
#100 1¼″ 9 – 60 E, F, J S, D 7.21
#120 1½″ 9 – 45 F, J, M S, D 8.63

Full tooth count range for each chain size available — contact us for specific de/dp dimensions. Hub width varies by strand configuration and bush series selected.

Maintenance Cost Comparison — QD vs Setscrew Bore Over 10 Years

The higher initial cost of a QD sprocket (sprocket + bush vs sprocket only) is typically recovered within the first or second maintenance cycle, depending on shaft access. A grain elevator head shaft requiring annual sprocket inspection illustrates the comparison:

Setscrew Bore — 10 Annual Cycles

  • Year 1: 4 hours access + 2 hours puller removal + 2 hours shaft inspection and cleanup
  • Years 2–5: Increasing shaft damage — 50% chance of shaft replacement at Year 4
  • Years 6–10: Shaft replacement ($800–$1,500) + sprockets ($200) each cycle
  • Average labour per removal: 3–5 hours per position

10-year total (3-position shaft): ~$8,000–12,000

QD Bushing — 10 Annual Cycles

  • Year 1: 2 hours access + 20 minutes QD removal per position
  • Years 2–10: 30 minutes removal per annual inspection
  • Shaft remains undamaged — no puller marks, no setscrew brinelling
  • Same QD bush reusable 5–8 cycles
  • Average labour per removal: 30–45 minutes per position

10-year total (3-position shaft): ~$1,800–2,500

Figures are illustrative estimates based on typical industrial labour rates and shaft replacement costs. Actual savings depend on shaft access, labour cost and maintenance frequency. The QD advantage increases with maintenance frequency and shaft diameter.

Τεχνικά Χαρακτηριστικά

Korea Ever-Power QD quick disconnect bushing sprocket ANSI B29.1

Self-Releasing Split Bush

The QD bush is split lengthwise — when the cap screws are reversed into the removal holes and tightened, the screw threads bear against the hub face and pry the bush out of the taper. The split in the bush allows it to open slightly as it ejects, releasing the shaft grip. The entire removal action is done with the same hex key used for installation — no puller, no impact tools, no heat. On a 2-inch shaft with an SF QD bush, removal takes under 5 minutes even in a confined space.

ANSI B29.1 Tooth Profile

The tooth profile machined to ANSI B29.1 is the same on QD hub sprockets as on all other Korea Ever-Power American standard sprockets. A like-for-like replacement from a setscrew bore to a QD bush sprocket at the same tooth count and chain number requires no chain changes. Run with ANSI roller chain of the same chain number for correct engagement.

Compatible with All QD Bush Suppliers

Korea Ever-Power QD sprocket hubs conform to the MPTA (Mechanical Power Transmission Association) standard QD taper profile — the same standard used by Dodge, Rexnord, Fenner, Emerson and all other major American QD bush suppliers. Any compliant QD bush from any supplier in the correct letter code will fit our hub without modification. You can source replacement bushes locally in North America from any industrial distributor.

Keyway in Hub & Bush

The QD bush is typically supplied with a keyway already machined in the bore, aligned with a keyway in the hub. This provides both taper friction grip and a positive mechanical key drive — the belt of suspenders approach standard for American heavy drives. For drives with high shock loading or frequent reversal, specify "keyed QD" when ordering. Plain bore (friction only) is also available and is adequate for the majority of steady unidirectional drives.

Αλυσίδα Συνδυασμού & Σχετικά Προϊόντα

ANSI roller chain #40 #60 #80 #100 for QD bushing sprockets

Matching ANSI Roller Chain

Match each QD sprocket with ANSI B29.1 roller chain in the same chain number. Standard, H-series heavy duty, self-lubricating and stainless variants available for all sizes from #35 through #120.

View Driving Chains →

Korea Ever-Power leaf chains for forklifts and hoists

Αλυσίδες φύλλων

BL and LH series leaf chains for forklift masts, industrial door drives, and hoist mechanisms. Tensile ratings from 11 kN to over 1,600 kN.

Δείτε τις αλυσίδες φύλλων

Korea Ever-Power engineering chains for heavy conveying

Αλυσίδες Μηχανικής

Welded steel, cast iron, and forged chains for heavy-duty industrial conveying in steel mills, cement plants, mining, and chemical processing.

Δείτε τις Μηχανικές Αλυσίδες

Korea Ever-Power stainless steel roller chain

Αλυσίδες από ανοξείδωτο χάλυβα

SUS304 and SUS316L roller chains for food, pharmaceutical, and chemical environments. Suitable for washdown, elevated temperature, and corrosive media.

Δείτε τις αλυσίδες SS

γεωργική-αλυσίδα-1

Γεωργικές Αλυσίδες

CA, CC, and corn-chain series for combine harvesters, cotton pickers, balers, and spreading equipment. ISO 487 / ASME B29.100 standard.

Δείτε τις Γεωργικές Αλυσίδες

Request a Quote — QD Bushing Sprockets

Specify ANSI chain number, tooth count, strand and QD bush series (JA/SH/SK/SF/E/F/J/M) with shaft bore in inches. QD bush supplied with or separately from sprocket. Response within one working day.

Επιπλέον πληροφορίες

Συντάκτης

Cxm

Σχετικά προϊόντα