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new type shock absorber

new type shock absorber

new type shock absorber

(OP)
I am designing a chambered shock absorber as opposed to a valved shock absorber. It is based on a monotube gas shock absorber but uses bottlenecks that fill up with fluid and delay the ram from sinking for about 1/10th of a second instead of the traditional method. It's application is different from traditional shocks in that I need to sieze up the ram from moving temporarily instead of dampening vibrations and supporting a sprung weight, like in a car shock. If I wanted to use the proccess called ECM to biuld the product quickly and uniformly what material should I make the body of the shock from(cylinder portion)? Also the the ram rod and especially the sealing material are of great importance.

RE: new type shock absorber

Typical piston rods are manufactured from SAE 1035 or 1045 that is induction hardened and plated with hard chromium.  The bodies are typically tubes that are mandrel drawn for improved dimensional capability (reduced errors & variation) and higher mechanical properties.  If you plan to machine the body out of steel bar, you will likely need to use SAE 1018 cold drawn bar, with a final wall thickness > 2.5 mm.  With regard to seals, do you mean the seal at the top end of the body or do you mean material that surrounds the piston and slides along the body ID?  The former are typically NBR rubber with a durometer of ~ 80-85 shore A while the latter are PTFE-based blends.  You can machine PTFE stock into the desired shape or look for pre-existing materials such as those from T-Lon (http://www.t-lon.com/).

RE: new type shock absorber

(OP)
This shock will have to handle an excessive amount of force for a short amount of time. The ramrod will execert between 55,000 and 80,000 force pounds in 4/10 of a second, the ram is approx. .850" +/- .002" OD. Since this is well beyond what a normal shock will handle I was planning on using SAE 6150 for the shock body (cylinder portion) and SAE 6150 case hardened with SAE 8620 for increased wearability for the ram rod portion. I was planning on sheet metal seels for the top end of the shock and a wall thickness of 3/16". Finally I planned on rolling the ends to prevent leaks,I hope this will create a sufficently strong shock to handle these pressures. Does this appear sufficent enough to create a shock strong enough to handle the above indicated pressure? The cylinder has an OD of 3.5" an over all length of 17" and a rod travel of 8 or 9".   

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