MintJulep and unclesyd,
Thanks for the replies.
MintJulep: Here is info on bores. There are two stepped bores.
1st bore
Cast bore 3.325" dia
depth of cast bore 1.514"
Machine finished bore 3.375" dia
2nd bore
Cast Bore 3.450" dia
depth of cast bore 1.056"
Machine finished bore 3.500" dia
Need 16 to 32 microinch surface finish in 3.00 inch bore of alum die casting. Piston O-ring must seal 2500 psi on this surface.
First attempt to machine the required finish resulted in rougher finish (45-70). Part is machined on a Mazak machine. Hand polished bore and got required finish, but...
Have received another matl composition of material and it say the material is 20CrMnTi with following chemicals:
.21 C, .26 Si, .93 Mn, .04 S, .11P, 12.2 Cr, .5 Ni, .15 Cu, .7 Ti. The 12.2 Cr must have a displaced decimal point?
They are saying that 20CrNiMo is available only in large qtys and...
Sorry, I should have indicated that this material has been quoted as an alternate by a China manufacturer.
They are saying it is equal or better than 8620 for gears. My concerns are the differences in chemicals and whether or not it can be carburized to RC58-62, depth of .020 to .030 as...
Have been told this is equal or better than 8620 for gears which have hardness of RC 58-62.
Can anyone comment on this? Chemicals are quite different. The 20CR material shows no Moly and the Ni and Cr are a lot lower than 8620.
Is there a simple way to estimate the difference in heat transfer for two cases.
1. Two steel surfaces in contact
2. An small air gap between the two steel surfaces
Would this be approx. the diff in thermal conductivity of air vs. steel?
I failed to mention the SS bars are bolted to aluminum castings. Could there be a problem with galvanic corrosion?
Would a particlar type of SS be better?
Two of the bars are used to hold two castings apart and they see low loads so most any type of SS would be strong enough. They do not have to have high corrosion resistance as the castings are painted ductile iron and are not intended for use in a salt water atmosphere.
Low cost is also a...
Currently use a chrome plated formed bar which is 1/2" dia carbon steel with both ends bent down 90 degrees and flattened with holes in the turned down ends. The flattened end is approx. 1/4" thick. This is a tooled part and is chrome plated after forming.
Would like to try some type of SS bar...
kcj,
I was looking for technical info rather than legal info.
Most companies nowdays who want to stay in business have ongoing cost reduction programs and realize that any replacement critical component must be qualified by testing. The most expensive isn't always the best.
Hydromech,
I would like to respond to some of your points:
1) A counterbalance valve can be used for load control or speed control. Without it, the load would overspeed on lowering.
2) A counterbalance valve can have one or two cartridges, thus the description. If the valve has two...
Looking for a manifold mount valve (motor mounted) to operate at 2500 psi max and 15 gpm max using hydraulic fluid. Used for speed control. Cost needs to be less than $35.
Can be either bi-directional or uni-directional.
Have been using a 5/16" hex 4140 steel bar for 2 yrs and now can't locate. The bar is used as an input shaft and must be heat treated to Rc 20-26 and straightened within .020 in a 15" length.
Does anyone know where I can find this material?
An alternate of 12L14, heat treated to same hardness...
