SPROCKET SPROCKET NOMENCLATURE
Bottom Diameter Diameter The diameter of a circle tangent to the bottoms of the (B.D.) tooth spaces.
Caliper Diameter Diameter Since the bottom diameter of a sprocket with odd number of teeth cannot be measured directly, caliper diameters are the measurement across the tooth spaces nearly opposite.
Pitch Diameter Diameter - The diameter across to the pitch circle, which is the circle (P.D.) followed by the centers of the chain pins as the sprocket Revolves in mesh with the chain.
Outside Diameter Diameter - The measurement from the tip of the sprocket tooth (O.D.) across to the corresponding point directly across the Sprocket. It is comparatively unimportant as the tooth length is not vital to proper meshing with the chain. The Outside diameter may vary depending on type of cutter Used.
Hub Diameter Diameter (HOD)
That That dist distan ance ce acro across ss the the hub hub from from one one sid side e to to ano anoth ther er.. This diameter must not exceed the calculated diameter of the inside of the chain sidebars.
Maximum Sprocket - Maximum Sprocket Bore is determined by the required Bore hub wall thickness for proper strength. Allowance must be made for keyway and setscrews.
Face Width -
Face width is limited in its maximum dimension to allow Proper clearance to provide for chain engagement and Disengagement. The minimum width is limited to provide the proper strength to carry the imposed loads.
Length Thru Bore Length gth Thr Thru u Bo Bore (or (or L.T L.T.B .B..) mu must be suf suffficie icien nt to to al allow low (LTB) a long enough key to withstand the torque transmitted by The shaft. This also assures stability of the sprocket on The shaft.
BASIC SPROCKET STYLES AS PER AMERICAN MANUFACTURERS STANDARDS
Style A - Flat sprocket with no hub extension either side.
Style B - Sprocket with hub extension one side. Style C - Sprocket with hub extension both sides. Style D - Sprocket with a detachable bolt on hub attached to a plate.
MULTIPLE STRAND SPROCKETS
Multiple Strand Sprockets – Sprockets – Listed using a letter prefix starting with the letter “D” for Double Strand, “E” for Triple Strand, and “F” for Quadruple, etc. In addition to the four specific types, sprockets may also be made in various other styles.
SOME OTHER COMMON STYLES •
QUICK DETACHABLE SPROCKET
The QD (quick detachable) sprocket; here a tapered bushing is bolted into the bore machined in the sprocket. This bushing, when inserted into the sprocket, compresses onto the shaft providing a tight grip. •
SPLIT TAPER TYPE SPROCKET
The ST (Split (Split Taper) is another style of bushed sprocket. The bushing is similar to the QD style except it has an external key that fits into the driven product. •
BORED TO SIZE SPROCKET
•
DOUBLE PITCH SPROCKET
Series C-2000 chains have rollers of the same diameters and widths as American Standard Roller Chains of one half the conveyor chain pitch. Engaged by every other tooth, DOUBLE PITCH sprockets have two teeth per chain pitch. During each revolution only half the teeth function effectively. Sprockets with odd numbers of teeth will allow any given tooth to engage only on every other revolution, automatically increasing sprocket life. Double duty sprockets with even number of teeth may be manually advanced one tooth periodically. Sprockets for the C-2002 series chain with carrier rollers are cut with space cutters or standard hobs for the American Standard roller Chain of the same diameter. Each sprocket tooth meshes with these chains. Double-duty sprockets cannot be made for double pitch chain with Carrier Rollers. •
TAPER BUSHED SPROCKET
The TB (taper bushed) sprocket is another style of an interchangeable bushed sprocket, which provides a positive grip on a driven shaft.
•
SPLIT TYPE SPROCKET
A split type sprocket is used in place of solid type to allow quick installation without disruption of shaft and alignment. •
SHEAR PIN TYPE SPROCKET
A shear pin type hub is bolted to a sprocket providing an overload device; as sprocket torque ratings are exceeded the shear device disengages sprocket from drive. •
DOUBLE SINGLE TYPE SPROCKETS
Double-Single Sprocket - Many installations of conveyor rolls or chains require a sprocket for use with two single strand chains through transmitting power from one roll or chain shaft to the next. A double strand sprocket is wide enough to operate with two single chains. These may be made up of two like sprockets or as a `Compound Double-Single, which is a combination of two sprockets of different pitch and/or number of teeth.
AMERICAN SPROCKET MANUFACTURERS SPROCKET CODING SYSTEM Sprocket nomenclatures provide the chain pitch number written to the left of the hub style code letter followed by the number of teeth in the sprocket . CODING SEQUENCE MULTIPLE STRAND CODE
(a)
CHAIN PITCH NO.
HUB STYLE CODE
NO. OF TEETH
MULTIPLE STRAND CODES:-
If the the spro sprock cket et is to be multipl multiple e strand strand,, the the pref prefix ix code code lett letter er is adde added d to the the beginning of the part number . number . FOR DOUBLE STRAND FOR TRIPLE STRAND FOR QUADRAPLE STRAND (b)
- Letter ‘D’ - Letter ‘E’ - Letter ‘F’
CHAIN PITCH NO. ISO CODE 06 08 10 12 16 20 24 28 32
(c)
METRIC CODE 25 35 40 50 60 80 100 120 140 160 180 200 240
PITCH SIZE ¼” 3/8” ½” 5/8” ¾” 1” 1 ¼” 1 ½” 1 ¾” 2” 2 ¼” 2 ½” 3”
HUB STYLE CODE
A - Flat sprocket with no hub extension either side. B - Sprocket with hub extension one side. C - Sprocket with hub extension both sides. D - Sprocket with a detachable bolt on hub attached to a plate.
(d) If the sprocket is to be bored for QD, Taper Bushed or MST, the center hub letter is changed. For QD (Quick Detachable) and MST (Martin Split Taper Type) styles the letter designation of the bushing is used in lieu of the hub style code.
Common bushing style codes: -
JA, SDS, SH, SK, SF, E, F, J, M etc. (for QD style sprocket) H, P, Q (for MST style sprocket)
(e)
Suffix of ‘H’ is added if the teeth are to be heat treated.( Hardened teeth).
(f)
If a taper bushing is to be used, the two letters ‘TB’ are added behind the hub code letter .
(g)
In some instances, the material from which sprocket is to be manufactured will be added into the part number as a suffix.
For example: SS - Stainless Steel Material NM - Non-Metallic BR - Brass or Bronze Material CD - Cadmium Plated Zi - Zinc Plated Ni - Nickel Plated CH - Chrome Plated (h)
For DOUBLE For DOUBLE PITCH SPROCKET chain pitch no. is replaced by double pitch code. DOUBLE PITCH CODE STANDARD ROLLER 2040 2050 2060 2080
DOUBLE PITCH CARRIER ROLLER 2042 2052 2062 2082
1” 1 ¼” 1 ½” 2”
In DOUBLE SINGLE TYPE SPROCKET letter ‘DS’ is added in place of (i) multiple strand code.
For bored For bored to size sprockets letter ‘ BS’ is used.
EXAMPLES: 1)
35 B 8
35
- CHAIN PITCH CODE (metric) Pitch size- 3/8”
B
- HUB STYLE CODE (sprocket with hub extension on one side)
8
- NO. OF TEETH
2)
35 BS 9
- refer (j)
3)
- BORED TO SIZE SPROCKET 35 B TB 8 TB
-refer (f)
BS
4)
-refer (g)
- CHAIN PITCH CODE (ISO) Pitch size- 5/8”
-refer (b)
- ‘J’ TYPE BUSHING (Quick Detachable Sprocket)
-refer (d)
2060 B 18
2060 9)
- STAINLESS STEEL SPROCKET
D 140 J 35
J
8)
-refer (a) -refer (e)
D 10 A TB 14
10 7)
- DOUBLE STRAND - HARDENED TEETH
100 B 11 SS
SS 6)
-refer (c)
D 35 B TB 19 H
D H 5)
- TAPERED BUSHING USED
-refer (b)
- DOUBLE PITCH CODE (Standard Roller) 1 ½” double pitch
DS 50 A TB16H
-refer (h)
DS
- DOUBLE SINGLE TYPE SPROCKET CODE
-refer (I)
ROLLER CHAIN DIMENSIONS Most manufacturers of sprockets conform to the ANSI (American Standards Institute) Following are the tables for roller chain dimensions as per ANSI standards. Riveted Chain Width*
Average Tensile Strength
STANDARD SERIES CHAIN .130 .237 .37 .130 .237 .63 .130 .237 .88
.34 .59 .84
875 1750 2626
3/16 3/16 3/16 3/16 3/16 3/16
.200 .200 .200 .200 .200 .200
.356 .356 .356 .356 .356 .356
.56 .96 1.36 1.76 2.16 2.57
.50 .90 1.31 1.70 2.11 2.51
2100 4200 6300 8400 10500 12600
40 40-2 40-3 40-4 40-6
5/16 5/16 5/16 5/16 5/16
.312 .312 .312 .312 .312
.475 .475 .475 .475 .475
.72 1.29 1.85 2.42 3.56
.67 1.24 1.80 2.37 3.51
3700 7400 11100 14800 22200
41
1/4
.306
.383
.65
.57
2000
50 50-2 50-3 50-4 50-5 50-6
3/8 3/8 3/8 3/8 3/8 3/8
.400 .400 .400 .400 .400 .400
.594 .594 .594 .594 .594 .594
.89 1.60 2.31 3.03 3.75 4.46
.83 1.55 2.26 2.97 3.69 4.40
6600 13200 19800 26400 33000 39600
60 60-2 60-3 60-4 60-5 60-6
1/2 1/2 1/2 1/2 1/2 1/2
.469 .469 .469 .469 .469 .469
.712 .712 .712 .712 .712 .712
1.11 2.01 2.91 3.81 4.71 5.60
1.04 1.94 2.84 3.74 4.64 5.53
8500 17000 25500 34000 42500 51000
80 80-2 80-3 80-4
5/8 5/8 5/8 5/8
.625 .625 .625 .625
.950 .950 .950 .950
1.44 2.59 3.74 4.90
1.32 2.47 3.62 4.79
14500 29000 43500 58000
ANSI Number
Roller Width
25 25-2 25-3
1/8 1/8 1/8
35 35-2 35-3 35-4 35-5 35-6
Roller Diam.
Inside Link Plate Height
Cottered Chain Width*
80-5 80-6
5/8 5/8
.625 .625
.950 .950
6.06 7.22
5.94 7.10
72500 87000
Roller Diam.
Inside Link Plate Height
Cottered Chain Width*
Riveted Chain Width*
Average Tensile Strength
STANDARD SERIES CHAIN .750 1.187 1.73 .750 1.187 3.14 .750 1.187 4.56 .750 1.187 5.97 .750 1.187 7.38 .750 1.187 8.78
1.61 3.02 4.43 5.84 7.25 8.66
24000 48000 72000 96000 120000 144000
*Dimensions *Dimensions are across pins.
ANSI Number
Roller Width
100 100-2 100-3 100-4 100-5 100-6
3/4 3/4 3/4 3/4 3/4 3/4
120 120-2 120-3 120-4 120-5 120-6
1 1 1 1 1 1
.875 .875 .875 .875 .875 .875
1.425 1.425 1.425 1.425 1.425 1.425
2.14 3.93 5.72 7.52 9.31 11.10
2.00 3.79 5.58 7.38 9.17 10.96
34000 68000 102000 136000 170000 204000
140 140-2 140-3 140-4 140-6
1 1 1 1 1
1.000 1.000 1.000 1.000 1.000
1.662 1.662 1.662 1.662 1.662
2.31 4.24 6.16 8.09 11.94
2.14 4.07 6.00 7.93 11.78
46000 92000 138000 184000 276000
160 160-2 160-3 160-4 160-6
11/4 11/4 11/4 11/4 11/4
1.125 1.125 1.125 1.125 1.125
1.900 1.900 1.900 1.900 1.900
2.73 5.04 7.35 9.66 14.27
2.54 4.85 7.16 9.47 14.09
58000 116000 174000 232000 348000
180 180-2 180-3
113/32 113/32 113/32
1.406 1.406 1.406
2.137 2.137 2.137
3.15 5.75 8.34
2.88 5.48 8.07
76000 152000 228000
200 200-2 200-3 200-4 200-6
11/2 11/2 11/2 11/2 11/2
1.562 1.562 1.562 1.562 1.562
2.375 2.375 2.375 2.375 2.375
3.44 6.26 9.08 11.90 17.52
3.12 5.94 8.76 11.58 17.21
95000 190000 285000 380000 570000
240 240-2
17/8 17/8
1.875 1.875
2.812 2.812
4.06 7.52
3.72 7.18
130000 260000
*Dimensions *Dimensions are across pins.
Reference URL’s 1. http http://w ://www.m ww.mart artinsp insprock rocket.c et.com/ om/spro sprocket cket.htm .htm
2. http://www.amet http://www.ametric.com/c ric.com/catalog/sta atalog/standard/02 ndard/02_ansispro _ansisprockets.pdf ckets.pdf 3. http http://w ://www.d ww.drive rivesinc sinc.com .com/rol /roller-P ler-PDFs/ DFs/roll rollr-pre r-premim mimp2.p p2.pdf df 4. http://www.mccc http://www.mccchain.com hain.com.tw/produc .tw/product/Roller t/Roller%20Chain %20Chain%20index.h %20index.htm tm
