We recently took the decision to include auto hauling equipment to our product line. We are now in the process of building a solid inventory of auto hauling supplies to include chains, auto hauling straps, J hooks, winches and more. One of the items we already carry is the G70 tow chain. In this post, we will explain what the chain is used for and what the grade 70 designation means.
For starters, a tow chain in the 21st century is not used in the same way tow chains were deployed 30 or 40 years ago. A standard tow chain is not meant to be the primary means of securing a vehicle to a wheel lift or flatbed tow truck. It is intended to be a safety attachment to prevent a vehicle from being completely separated from its tow vehicle in the event the primary attachment fails or becomes detached.
On a wheel lift tow truck, for example, the G70 tow chain is attached to the frame of the car being recovered after the car has already been secured to the hydraulic dolly with auto hauling straps. The tow operator may use axle or tire straps to tightly secure the vehicle. The tow chain is added as a secondary safety device. In the event of primary attachment failure, the tow chain allows for a safe and controlled stop.
The G70 designation signifies that a tow chain’s tensile strength is rated at 70. A tow chain may be marked with a 7, 70, or even 700 to signify the G70 grade. With that out of the way, let us talk tensile strength for any of our readers who might not understand what that means.
Tensile strength is the maximum amount of force a chain can withstand before breaking. It is also known as break strength. The higher the grade, the greater the tensile strength of the material in question. Where tow chains are concerned, tensile strength is heavily influenced by the volume of carbon in the steel. A lower tensile strength indicates a lower carbon volume.
A typical G70 towing chain possesses enough tensile strength to safely handle a car in the event a tow truck’s primary attachment fails. But the G70 chain is not strong enough for overhead lifting. This is why these chains are designated for towing rather than lifting and rigging.
Link Size and Finish
Industrial chains also come with labels indicating the chain-link size and finish. This is not necessarily important to tow truck operators, but we will discuss both just for information’s sake.
Chain-link size deals with the elongated size of each individual link. Chains with longer links might be more useful in some flatbed auto hauling applications because they make it easier to attach shackle bolts anywhere along the length. Chains with smaller links may limit shackle bolts to the ends.
As for the finish, one option is hot-dipped galvanized steel. Hot-dip galvanization is a process that creates a chain capable of withstanding a variety of conditions, including exposure to road salt. Stainless steel and zinc-plated gold chromate finishes are additional choices for tow operators.
Now you know the basics of the G70 towing chain. Mytee Products carries an excellent G70 safety chain manufactured by Ancra, in two different sizes. It has a working load limit of 4700-6600 pounds and conforms to ASABE and NACM standards.
For all your professional towing needs, Mytee is your leading supplier. Please contact us for anything you need, even if you do not see it on our inventory list.