Brake pipe

Brake pipes are not black or white- pass or fail, too much grey in between and there lies the problem. VOSA need to re-word the manual to try and eliminate the grey. maybe members can help them out by coming up with suggestions and posting them here on the forum. as always with brake pipes just my opinion.

I still think the point of what the manual information column is telling us is being missed or misunderstood, maybe because NTs want to make their own judgement and decide maybe personally when the brake pipe is excessively corroded.

The manual is the definitive guide here, right or wrong.

To correctly assess the condition of corroded metal brake pipes, surface dirt might have to be removed.

First point here is that surface dirt might have to be removed, not surface corrosion, which is a different matter. VOSA did a video on this which has been put onto a later DVD, they actually show you what they mean.

This might require light scraping with the Corrosion Assessment Tool ‘spade end’.

Notice that the guidance given tells us that we must only use an approved tool. See the DVD.

Care must be taken not to damage any protective coating.

Tools used other than the approved tool could possibly cause unnecessary damage to the brake pipe.

This next point is also an important criteria to be met, and overruling is not following the guidance given.

Chafing, corrosion or damage to a rigid brake pipe so that its wall thickness is reduced by 1/3 (e.g. approximately 0.25 mm for typical hydraulic brake pipe) is a reason for rejection

The point of everything I keep saying beyond doubt is trying to get people to see that you cannot visually see any point of a pipe reduce in thickness by 1/3 (0.25mm).

For a start you can look at the brake pipe to your hearts content I don't care, unless that pipe has necked at some point you cannot look at the pipe and say it's wall thickness has reduced, we are not talking here about the diameter of the pipe, that your eyes see but the wall thickness, which you cannot see.

I admit that yes there will be brake pipes out there that have necked and visually you can see the pipe diameter at a point will be reduced, and yes in that instance I would agree it would be a fail, but I must stress I am talking about pipes in general condition with surface corrosion on them.

I have seen many brake pipes failed by Test Stations only to find that another mechanic has rapped emery paper round the pipes and cleaned off the surface corrosion, then visually the pipe looks good like in Nitros second picture, which then if you failed it again at retest and an appeal took place, if the pipe then looked similar to the second picture nitros posted, you loose the appeal.

I am not saying that the decision to make is easy, but unless the evidence was such that there was absolutely no doubt the condition of the pipe was none serviceable, I would think a VOSA VE would give the benefit of doubt and pass and advise.

I base that decision on the fact that every time I have been on a refresher training course and brake pipes have been mentioned, the trainers have always said pass and advise, even when greased.

There are no arguments above and I am also entitled to my opinion as well as all other members.

Davidg

Nov 13, 2013 0:54:16 GMT 1 baz657 said:

Nov 13, 2013 0:42:33 GMT 1 davidg said:

but I can see that you work along the same lines as me and trust that if the brake pressures don't burst the pipes then passing and advising in these instances is all we can do...

That's not what I said. Re-read my post again, noting the bit about coming back for retest.

Sorry if I misunderstood you Baz, but if you are saying you fail them on test and the presenter/mechanic cleans them and you then pass them on retest, could you end up being reported for failing pipes you should not have failed?

I totally agree that this brake pipe issue is a mind field we are all trapped in, which is why I said at the very beginning if they don't leak, I don't fail um, unless there is absolutely indisputable evidence that says the pipe must fail. 

If anyone from VOSA ever disagreed with me, I would tell them I (cannot) prove they are less than 1/3(0.25mm) and the working pressure internally is much greater than my best visual examination in most cases, so I feel I made the right decision, unless it leaks then its failed anyway.