Replies to this message

Re: chain drive design
Re: chain drive design -- senthilkumarv	Post Reply	Top of thread	Forum

Posted by: specdor ® 10/19/2005, 22:49:11 Author Profile Mail author Edit

Chain drive design is as simple as looking in the book. Chain manufactures suggest a 10 to 1 safety factor. Chain manufactures do not give data as to materials used and manufacturing methods. Chain side plated are punched. Low end chains have a lot of distortion around the holes. High end chains have shot peened rollers to reduce wear. If you wanted to make a chain then you can control the materials and the manufacturing methods. I drive heavy machinery with #60 and #80 chain. Some chains stretch more than others. go figure

Post Reply | Recommend | Alert

Where am I? Original Top of thread

Re: chain drive design
Re: chain drive design -- senthilkumarv	Post Reply	Top of thread	Forum

Posted by: george2036n ® 08/25/2005, 17:37:30 Author Profile Mail author Edit

Get Catalog from any Chain Manufacture and a Book ANSI B29.1 a Roller Chain standards. This should answer most of your questions. As far as chain design,its based on chain working load or pull and pin bearing area,pin shear,tensile strength on the side plates. Wear is a property of pin bearing area,strength on two things,pin shear and tensile strength of the side plates. Working loard is about 10% of tensile strength,check Horse Power Charts from a chain catalog. George George2036n@netscape.net Modified by george2036n at Fri, Aug 26, 2005, 13:41:06

Post Reply | Recommend | Alert

Where am I? Original Top of thread

| |

Re: chain drive design
Re: chain drive design -- senthilkumarv	Post Reply	Top of thread	Forum

Posted by: sureshch2 ® 08/23/2005, 09:47:05 Author Profile Mail author Edit

Hi senthil, i had seen in this forum that u have worked on analysis of chain links and pins...can u provide the information regarding as how to design pins and links in the chain drive...i mean the calculating the deflections, bending moments etc., and the forces acting on pins... thanks

Post Reply | Recommend | Alert

Where am I? Original Top of thread

| |

Re: chain drive design
Re: chain drive design -- senthilkumarv	Post Reply	Top of thread	Forum

Posted by: ReubenAG ® 01/30/2004, 17:05:05 Author Profile Mail author Edit

What application are you looking at using a chain drive in? Restrictions on tensioning methods, shock loads on the drive/ driven shaft, noise, ability to lubricate the drive can all affect the final choice of chain and sprockets.First get hold of a chain and sprocket catalogue-most local suppliers are quite happy to dish these out. If it is a simple matter of transmittting power from one shaft to another, then you need to determine the power transmitted (P). It is also necessary to know the input speed and desired output speed to determine the sprocket ratio. If your application requires a long life, conventional wisdom says don't use a small sprocket with less than 18 teeth. However, I have seen karts with 10 or even 9 teeth on the small sprocket. Most of these guys put new sprockets on every race. \ Choose a number of teeth for the small sprocket based on the above and multiply by the transmission ratio to get the number of teeth for the big sprocket. As power = torque x rotational speed, determine the torque exerted on a sprocket (doesn't matter if it's the large or small sprocket). Get the sprocket pitch radius from the catalogue (Or Machinery's Handbook) and determine the chain tension. (Torque = tension x radius). Consult the catalogue for maximum chain tension permissible and choose a chain pitch that can tolerate the tension. Safety factor depends on the application - exposure to dirt/ absence of lubrication would necessitate a higher safety factor. It may be necessary to use a duplex or triplex chain.

Post Reply | Recommend | Alert

Where am I? Original Top of thread

| |

Re: chain drive design
Re: Re: chain drive design -- ReubenAG	Post Reply	Top of thread	Forum

Posted by: JonSmith ® 11/15/2005, 16:06:19 Author Profile Mail author Edit

Interested to follow up on this string. I'm designing a drive where the chain is fixed and a sprocket with tension idlers 'walks' along it to provide horizontal travel for a small hoist. I need to know if there is a limit (for wear, reliability) on the minimum circumference of the sprocket the chain will engage. It's looking like less than 60 degrees of arc at present. Any rules, references?

Post Reply | Recommend | Alert

Where am I? Original Top of thread

Re: chain drive design
Re: Re: chain drive design -- ReubenAG	Post Reply	Top of thread	Forum

Posted by: senthilkumarv ® 01/31/2004, 00:19:13 Author Profile Mail author Edit

thanks for the good reply i need more than u r details like how to manually calculate 1. roller busing fatigue life expectancy in hrs 2.permissible wear rate 3.stress on busing & pin 4.deflection etc....   have a nice day

Post Reply | Recommend | Alert

Where am I? Original Top of thread

| |

Re: chain drive design
Re: Re: chain drive design -- senthilkumarv	Post Reply	Top of thread	Forum

Posted by: ReubenAG ® 02/13/2004, 05:40:51 Author Profile Mail author Edit

Unfortunately I have only used chain drives in short term applications where the wear rate/fatigue lie has not been a concern. AS regards calculating the stresses on the bushes and pins, I have never really examined this properly - chain manufacturers like Renold go into calcs of this sort. A simplified view of the pin and bush is that the global tension force in the chain is carried as a "bearing pressure" on the pin and bush. If tensile force is T, the bearing pressure P = T/ (diameter of pin x length of the bush). One can simplify the pin as a simply supported beam with the bearing pressure carried as a uniformly distributed load (=Pxdiameter of pin to obtain load in Force/ unit length). This will induce shear forces and bending moments across the length of the pin. As regards deflection, are you referring to the permissible deflection of the chain when it is assembled (measured perpendicular to the line of the chain in the plane of the sprockets) or the "stretch" of the chain under load. If you are referring to static deflection, the manufacturer will publish figures for this. I have never seen any info on calculating the stretch of the chain under load- this is why spring loaded chain tensioners which adjust to changes in chain length are used in many applications. Modified by ReubenAG at Fri, Feb 13, 2004, 05:47:52

Post Reply | Recommend | Alert

Where am I? Original Top of thread