Maximum load on beam

[eberd]

What will be the approx. maximum load on a 4"x6" wooden beam, 14 ft long, when downward pressure is applied in the center of this beam?

The beam 7 ft high, supported at 2 places by 6"x 6" posts 14 ft apart.

The beam is laid down with the 4" side resting on top pf the post.

 

[JAE]

That depends on the species of wood and grade of wood.

 

[eberd]

To JCA, thanks for the quick response.

In reply to your comment, this 4"x 6" beam is pressure treated pine (.40 cca I guess) for outdoor use.

 

[SlideRuleEra]

Maximum (safe load for a good quality member) would be about 500 lb. which would give you bending stress of about 1200 psi, minimal shear, and 3/4 inch or so of deflection. Fourteen feet unbraced length should not be a problem for this size wood beam.
If this is for the swing that you mentioned in your previous posting, I would reduced that to 400 lb. since you could have moving and impact loads plus safety issues.