US Ratchet Strap (Cargo Strap) Specification

Automotive Engineering general discussion
#1

I’m looking for a specification document for US ratchet straps. Like this:

Rachet Straps

I’m specifically looking for information on geometry (width and thickness), minimum breaking loads and load-extension characteristics. From the link above it states:

image

That’s a lot of standards, and no reference numbers. Noted, I could google for a while but I thought some SI’ers might know offhand. Back in Blighty we just have a single British Standard to refer to.

Is there a US equivalent?

#2

Hmm, not an expert by any means, but my usual approach to a problem like that is to visit McMaster.com and look up the part…

They list a “DOT compliant” ratchet strap, and drilling down on one of those gives a list of specs:

ASME B30.9,
D.O.T. Compliant 49 CFR 392.9,
D.O.T. Compliant 49 CFR 393.100,
WSTDA RS1, WSTDA RS1-HP, WSTDA TH-1

Hopefully those answer your questions. I have no idea why there are so many different specs for what appears to be a single type of ratchet strap…welcome to America.

1 Like
#3

I’ll keep quiet about the MIL-spec world unless you want to open THAT can of worms.
Everything they procure, the write a spec for.

I’m also a little reluctant to dive into it - I’m sure there’s something - lots, in fact. The problem is sorting out the overwhelming amount if information, and see my way through a subject like that. So if you really need a Mil-spec for a cargo strap, I know where to find it.

1 Like
#4

Thank you folks. I searched through the specs mentioned above, and unfortunately I can’t find what I’m looking for.

ASME B30.9 is for slings of all sort
WSTDA RS1 appears to be polyester round slings
WSTDA TH-1 is for the threads used
D.O.T. Compliant 49 is for the transportation of hydrocarbon sample cylinders

I tried searching for MIL-spec stuff, but could only seem to find information related to aircraft. I’m unsure how the US military works so don’t know if that would be the same things used for road transport as well. I will keep digging.

#5

So I take it your spec has to be more specific than “Erickson”.

MIL spec is a special world.

From: https://quicksearch.dla.mil/qsSearch.aspx

  • MIL-S-43828A Strap, Webbing, Cargo Tie Down, Lightweight Pack Frame, M-1972 (No S/S Document)|
  • MIL-S-43828A STRAP, WEBBING, CARGO TIE DOWN, LIGHTWEIGHT PACK FRAME, M-1972 (NO S/S DOCUMENT)|
  • A-A-59884 E-Track Ratchet Strap, Cargo, Tie Down Assembly|
  • MIL-STD-2073-1E Standard Practice for Military Packaging
  • MIL-STD-2073 DOD MATERIEL, PROCEDURES FOR DEVELOPMENT AND APPLICATION OF PACKAGING REQUIREMENTS (S/S BY MIL-STD-2073-1)

These might not help you in the end. I’m 10 minutes into searching and as I expected the paths to beat down are growing fast.

1 Like
#6

Start here.

1 Like
#7

Thanks Sparweb

Following on from the suggestions given, I found:

WSTDA-T-1 Standard Specification for Synthetic Web Tie Downs
WSTDA-T-4 Synthetic Webbing Tie Downs
WSTDA-TM-1 Strength and Elongation Recommended Test Method for Sling and Tie Down Webbing

Are all a good start.

Mint

I shall take a look

Thank you

#8

So I contacted a US manufacturer. They advised me that regarding elongation limits, there are none in the US. They also do not need to test for it, its just a recommendation. The stretch is whatever it is. In the UK, the standards restrict it to 7% at full lashing capacity.

They gave me some generic ranges which they work to though, which was helpful.

Thank you for your help.