High Shoulder Towball
50mm high shoulder tow ball suits Al-ko®, Ark® and Hyland Hitch off-road couplings.
In our opinion, the Couplemate high tensile tow balls are the best on the market and an excellent investment.
Importantly, our tow balls are tested however, there is no procedure for imported tow balls to be tested.
What specifications are available?
- 25mm Shoulder.
- 52mm-62mm Thread length.
- 22mm diameter UNF thread to suit most tow bars.
- High tensile
The high shoulder allows great articulation of off-road couplings over standard equipment.
Standard tow balls can touch and put a lot of force on the edge of the receiver bar and may cause coupling, tow ball and chassis damage.
Why it is necessary to test tow balls
Couplemate tow balls have been tested to comply with AS4771.2 where balls are examined to 85kN and held at 85kN for not less than 10 sec. Watch this interesting video. Watch the computer monitor in the background.
What is 85kN?
85kN is the force applied to the tow ball during testing (85kN = 8.667 tonne).
Therefore, 3.5t tow balls must be tested to satisfy the Australian Standard and to a min standard of (8667.59kg).
Couplemate manufacturers American tow balls (2″ and 2 5/16″) and rates them to 3.5t. Purchase here.
Tow Ball Scales
Coupling weight is critical to ensure your rig running true and braking correctly. Too much tow ball weight overload your tow vehicle and make it overrun its braking ability.
Tow weight ball scales help identify how much weight you should move back onto your trailer axles thereby lightening the load on your tow bar.
The correct weight and a level chassis play a huge role in effective and efficient towing.
Couplemate guarantees tow balls for life against faulty manufacture. If your Couplemate high tensile tow ball fails you for any reason, we will replace it.
High Tensile 25mm High Shoulder Tow Ball
3500kg extended shoulder tow balls are manufactured in Australian by Couplemate. Thank you for your support.
A standard shank tow ball shoulder is approximately 12.5mm. This size shank fits all highway couplings except some off-road couplings.
Offroad couplings can foul the tow bar tongue when towing through gullies or river beds on an angle. There is the possible damage that could be caused to your towing equipment using a standard size shoulder on a tow ball.
Couplemate developed a high tensile tow ball to allow the full rating of 3500kg. A much higher rating is achievable due to the grade of high tensile we used.
Galvanising and Plating
Galvanising and plating is a big issue when talking about “but will it be strong enough.”
There has been a fair amount of research on galvanising and spring weakness due to the galvanising process. Click here for the full report.
Will galvanising or plating affect my product strength?
Yes, strength tests in the full test report above states strength reduce the product rating by 0.4%, The tolerance here we would take notice is 1%.
In effect, there is no negligible effect on product load rating. Click this link to read our article on galvanising.
How can I be sure my the ball rating will not be affected by galvanising?
A good question deserves the right answer.
After plating, Couplemate tests tow balls to AS 4177.2—2004.
Also required as part of testing is a certificate that the coupling balls have undergone a de-embrittlement process.
Finally, so you have read about embrittlement? Certificates are required with each batch to ensure products are free of hydrogen embrittlement.
Couplemate Trailer Parts sells only the best quality 50mm x 25mm High Shoulder Towball and caravan spare parts throughout Australia.
Customers are welcome to either pickup or take advantage of our low freight rates. Express shipping to Melbourne, Sydney, Brisbane, Perth, Adelaide, Darwin, and Hobart.
We also ship products to New Zealand via Australia Post Air Express.
© Steve Wotherspoon June 10, 2014. Images and text may be copied, provided a link back to the copied page and the source is displayed where the content or image is located.
Last Updated on