ASME B29.2M-2007 pdf download

ASME B29.2M-2007 pdf download.Inverted Tooth (Silent) Chains and Sprockets.
1 SILENT CHAINS 1.1 Nomenclature (a) Silent chain is a series of toothed links alternately assembled with pins or a combination of joint compo- nents in such a way that the joint articulates between adjoining pitches. As shown in Fig. 1, illustration (a), side guide silent chain has guide links which straddle the sprocketsides to control the chainlaterally. As shown in Fig. 1, illustration (b), center guide silent chain has guide links which run within a circumferential groove or grooves for lateral control. (b) Typical Links. Since joint components, connectors, and offset sections vary with each manufacturer, these items are not included in this Standard. See Fig. 2 for examples of typical links. 1.2 General Configuration Link contour may vary but must engage standard sprocket teeth so that joint centers lie on sprocket pitch circle. (a) 3 ⁄ 8 in. Pitch Chain and Larger. Chain widths equal to, or exceeding, two times the pitch have center guides. Narrower chains may be side guide or center guide. Chainwidths exceeding16times the pitchare notrecom- mended. (b) 3 ⁄ 16 in. Pitch Chain. Chain may be side guide or center guide as indicated in para. 1.8. (c) Maximum Chain Width. Maximum chain width should be limited to approximatelyeighttimes the pitch. 1.3 Numbering System (a) 3 ⁄ 8 in. Pitch Chain and Larger. Two letters (SC) as a prefix, one or two numerals indicating pitch in eighths ofaninch, and two orthree numerals indicatingnominal chain width in quarters of an inch. Thus, SC302 desig- nates a silent chain, 3 ⁄ 8 in. pitch by 1 ⁄ 2 in. nominal width, and SC1012 designates a silent chain, 1 1 ⁄ 4 in. pitch by 3 in. nominal width. (b) 3 ⁄ 16 in. Pitch Chain. Two letters (SC) as a prefix, a zero followed by a numeral indicatingpitch insixteenths of an inch, and two numerals indicating nominal width ofchain inthirty-seconds ofaninch. Thus, SC0309 desig- nates a silent chain, 3 ⁄ 16 in. pitch by 9 ⁄ 32 in. nominal width. NOTE: Where links are all of equal thickness 0.03 in. (0.76 mm), it is understood that the width indication also designates the total number of links across the width of the chain. 1 1.4 Tolerance for Chain Length (a) 3 ⁄ 8 in. Pitch Chain and Larger. Chains will be designed and manufactured to fit gage sprockets. Toler- ance for chain length for new chains may be over nomi- nal length 0.03 in./ft (0.76 mm/m) but must not be underlength. (b) 3 ⁄ 16 in. Pitch Chain. Chain length tolerance is 0.02 in./ft (0.51 mm/m) over nominal length but must not be underlength. 1.5 Measuring Loads (a) 3 ⁄ 8 in. Pitch Chain and Larger. Chain should be mea- sured under load of 25 lb ? pitch in inches ? width in inches + 20 lb (0.1724 N ? pitch in mm ? width in mm + 89 N). Length measurements are to be taken over a length of at least 12 in. (300 mm). (b) 3 ⁄ 16 in. Pitch Chain. The measuring load for 3 ⁄ 16 in. pitch silent chain shall be approximately equal to 1 lb (4.45 N) for each link in the total chain width, i.e., the load for SC0315 would be 15 lb (67 N). Length measure- ments are to be taken over a length of at least 12 in. (300 mm). 1.6 General Chain Dimensions for 3 ⁄ 8 in. Pitch Chain and Larger See Fig. 3 and Tables 1 and 2. 1.7 Chain Widths and Sprocket Face Profiles for 3 ⁄ 8 in. Pitch Chain and Larger See Fig. 4 and Tables 3 and 4. 1.8 Chain Widths and Sprocket Face Profile for 3 ⁄ 16 in. Pitch Chain See Fig. 5 and Tables 5 and 6. 2 SPROCKETS 2.1 Tooth Form Dimensions for 3 ⁄ 8 in. Pitch Chain and Larger See Fig. 6. 2.2 Tooth Form Dimensions for 3 ⁄ 16 in. Pitch Chain See Fig. 7.
2.5 Tolerances for Diameters, Over Pin Dimensions, and Eccentricity for 3 ⁄ 8 in. Pitch Chain and Larger See Tables 7 and 8. 2.6 Tolerances for Diameters, Over Pin Dimensions, and Eccentricity for 3 ⁄ 16 in. Pitch Chain See Tables 9 and 10. 2.7 Hub Diameters for 3 ⁄ 8 in. Pitch Chain and Larger See Table 11. [For other pitches ( 3 ⁄ 8 in. pitch and larger), multiply these values by pitch.] 2.8 Tabulation of Pitch Diameter, Outside Diameter, Over Pin Dimensions, and Guide Groove Diameter for Chain of Unity Pitch (Applicable to 3 ⁄ 8 in. Pitch Chain and Larger) See Table 12. [For other pitches ( 3 ⁄ 8 in. pitch and larger), multiply these values by pitch.] 2.9 Tabulation of Pitch Diameter, Outside Diameter, Over Pin Dimensions, and Guide Groove Diameter for 3 ⁄ 16 in. Pitch Chain See Tables 13 and 14.