Nissan Patrol 4x4 (Africa)

Hi Almal,

Soos jul sal sien op die forum het ek a towbar op wat my departure angle opneek. Ek het toe vir my die Nissan recovery hook gekry wat ek dan sal op sit in plek van towbar, maar ek wil graag weet wat die beste bolts is om te gebruik om dit mee vas te sit?


Kan ek die gewone galvinised bolts gebruik waarmee die towbar vas is of moet ek high textile bolts gebruik?


Dankie

Ek sou high tensile boute gebruik.

Efinately high tensile, either grade 8.8 (minumum) or grade 10.9.

Personally I would be hesitant to use grade 12.9, as although they are even stronger, they are a bit brittle.

Also, take note that while you do get high-tensile galvanized bolts, they are not as strong as they should be. Just get the black ones.

Furthermore, if you do a snatch recovery those boltsshould be replaced at the first opportunity thereafter.

Thank you for the answers that really helps.

I went for the 8.8 as that was what was in there with the galvanized ones. The black ones.

Peter may I ask what is the main difference between High Tensile and other bolts like the galvanized ones?

I found the thread on the High Tensile to be deeper cut as the galvanized ones?

Thanks again.

You have to wait for piet to give you the proper anwer all I can say it has to do with the amount of carbin ect in the steel better steel can take more torqe ect the harder the steel the stronger it is up to a point were it becomes brittle ...softer steel bends and cuts differt that's why the threads feels and looks better on the harder ones
The heating proseses with gal ones changes its properties

Ek het net laasweek my recovery hook gekry wat op die towbar point pas - en dieslefde boute gebruik as wat daar op was - ook maar goed ek het die thread raakgelees.

Dankie Jacques !!!!! Jy spaar my dalk groot ellende

NISMOnator wrote:Thank you for the answers that really helps.

I went for the 8.8 as that was what was in there with the galvanized ones. The black ones.

Peter may I ask what is the main difference between High Tensile and other bolts like the galvanized ones?

I found the thread on the High Tensile to be deeper cut as the galvanized ones?

Thanks again.

Jacques, there really shouldn't be any difference in thread form between different bolts of the same nominal thread size. In other words, any two M10 x 1.75 bolt's thread should be exactly the same (although of course there are allowable limits (manufacturing tolerances) that allow for minor differences). The real difference between the different bolts is in the materials they are made from, and particularly so in terms of their strength.

Quality Metric bolts should have a code on the back, this is called the grade. Normal galvanized bolts are grade 4.6

To use the code is sort-of simple, the first number multiplied by 100 is the Ultimate Breaking Strength (this is where it will break) of the bolt, in MPa. If you multiply the above number by the second part of the number, you get the Yield strength (the point at which it will start to permanently deform or bend/stretch).

So a grade 4.6 bolt will start stretching at 400 x 0.6 = 240MPa, while a grade 8.8 bolt will stretch at 800 x 0.8 = 640MPa, or nearly thre times the load.

The difference in thread depth you found is probably due to the galvanising being thicker in the thread grooves.

Baie dankie Tinus en Peter vir die antwoorde. Ek leer stadig maar verseker! :idea:

Plesier jan.dup, bly dit het iemand anders ook gehelp.

Dankie

Peter,
100% correct
All I have done for all my bolts (with very few exceptions) is to buy HT's and electro-galvanise them
At R8.80 a kg it is well worth it
They are a wee bit tighter, but it saves on loctite- and I get to unscrew them in the bush
Also, any threaded hole now has a bolt- never have to look for the right bolt- at R 300 it is a bargain, and I have spares

Can you please put a picture of the recovery hook on so I can see what it looks like

What is the cosgt and where to purchase?

Tx