A490 bolt in snug-fit holes

[trainguy]

Hi all.

Can anyone offer guidance on the diameter tolerances of the unthreaded part of an A490 bolt shank?

I would like to use these similarly to studs in an unthreaded hole.

The assembly has 4 - 1.5 inch dia bolts to connect a 4 inch thick assembly to a 1.5 inch thick steel mounting plate. I would like the 1.5 inch thick mounting plate to come pre-assembled with 4 bolts somewhat tight in the holes, then we'd present the mating assembly (with slightly oversized holes, and we'd add nordlock washers and nuts. We have a method developed that will prevent the bolts from turning when the nut is torqued.

Any comments?

 

[gtaw]

Have you reviewed ASTM A490 for the information you need? It may be there or in one of the reference documents listed in that standard.

Best regards - Al

 

[dimjim]

I would think the diameter would be a mmc condition
and that is what you are asking for. Bolts specs
do not care about the material and I think are all
the same regardless of material. The coating or finish
may increase this diameter however.

 

[CoryPad]

The ASTM standard only covers material properties. Dimensions are covered by ASME B18.2.6 Fasteners for use in Structural Applications. This standard is available from ASME for USD37.00.

http://catalog.asme.org/Codes/PrintBook/B1826_2006_Fasteners_use.cfm

Regards,

Cory

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[Screwman]

The body diameter tolerance is 1.531 / 1.470, so I don't think you'll be able to get any sort of a consistent press fit condition.

 

[trainguy]

Screwman,

Do you know the head size tolerance for width across flats for an M36 hex head bolt?

Thanks in advance!

tg

 

[CoryPad]

According to ISO 4014, an M36 bolt has a width across flats dimension of 55 mm nominal, 53.8 mm minimum, and a product grade B and reference to ISO 4759-1 for tolerances. ISO 4759-1 shows the tolerance to be h15, which for a nominal 55 mm size is 0 mm, -1.2 mm, which agrees with the ISO 4014 data.

Regards,

Cory

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[Tmoose]

Is the goal is to keep the bolts with the mounting plate, not to provide some kind of alignment?

Maybe I'd think about providing counterbores in the mounting plate so a pushnut could be used on each bolt. With typical thread conventions the threads may not extend within 1.5 inches of the head, so the pushnut would have to grip the body diameter.

http://www.aaronspushnuts.com/

http://www.connexusa.com/

Maybe even an O-ring tight on the bolt body

 

[Tmoose]

http://www.usatolerancerings.com/