Best/Safest way to Strap down Pipe ?

You’re off to a good start with those gut straps through the middle of the stack. I would throw two of those and 4 over the top. On the straps over the top alternate sides on the winches so two winches are on each side. The alternating pull will keep the stack from leaning.

 

Ditto that. I always prefer more securement then less.

 

It should be okay if the strapping on those bundles holds and they're always unloaded as bundles. However, I always wrap pipe with one or two belly-wraps; from the winch go under the load, over the top, back under the load to the opposite side. OR a ratchet and strap around the load (in the middle where you'll get the greatest deflection).

And stakes... ALWAYS stakes.

 

as Kyle says pulling to each side is the way to go with pipe of all types. A minimum of 3 and preferably 4 over all with at least 1 (in the middle or each end) over each layer will keep your pipe secure.
Fittings and valves should be "fenced in" by pipe if a mixed load or in wooden crates strapped down. If shipped singly put them butted against the front of the deck and individually strapped.
Nothing should move on the deck after tie-down including middle pipes or pieces.
Hydrants are noticeably heavier than pipe and each one (or layer) should be tied separately and on the bottom .
Portable straps are your friend on strait trucks.

 

I'm not a flatbed driver these days but I remember everything about what it required. I can't remember what kind of strap you called it but I do know when the forklift driver gets to the second one stacked on top of the first one you should throw a strap over that and then throw another strap on the one all the way up on top. Like I said I don't remember what they called that strap. You also put on what's called a smoke tarp over the top two stacks in the front of your load. You simply put the tarp on the front and tie it down to the steel banding that holds the pipe together with 4 bungee cords
The forklift driver will usually give you the option to do this on the ground before he sticks it up on top.

 

I see 4 or 5 side pockets. That pipe is light in weight so 4 inch straps through middle and over top evenly will do it.

 

1 strap and go just like all the local drivers do!! Lol but seriously, i tip my hat to u for asking this question. And i would agree with everything thats been said here. Good luck to u