Purpose of coiled spring around brake lines?

[tom h]

On stainless steel brake lines I bought from Inline Tube, they install the OEM-looking coil spring around the SS tube. The coil spring is zinc-plated steel, but in time it will rust.

What was the purpose of this commonly used coil spring? It's sometimes called a "protector", but the brake lines already seem so well protected from errant stones, I can't imagine much benefit.

It won't look absolutely OEM and "correct", but am thinking to cut off the coil so that the stainless lines' appearance won't be compromised by a rusting steel spring.

 

[tom h]

well, I was mistaken about the "coil spring wrap" being zinc plated steel. Inline Tube replied back, that the spring wrap is also stainless. I was misled because the coil spring was slightly magnetic, and most stainless is non-magnetic.

So probably I'll just leave the spring wrap in place.

 

[Ormand]

Actually, most stainless is magnetic. The 300 series is not, but the cheaper kind used for knives, and refrigerators and trim on cars is a 200 or a 400 series, and they are both magnetic. Just a little meaningless info!

 

[turbofish38]

If I'm not mistaken the purpose of the coiled wire is to keep the line from splitting. My books call it armour shielding. I was thinking I read somewhere that it acts as a shock absorber and absorbs the vibration or something like that. You only see the stuff on the bends so it kind of makes sense in a way. It might also be used as sheilding to keep something from rubbing on it.

 

[Gary Wells]

http://www.ssina.com/index2.html

some stainless steel info for those that need to know.

I think that the spring, in addition to the reasons mentioned above:
Helps avoid kinking.
Keeps the rubber from expanding past the expansion point in case of a weak spot such as a bubble that might rupture if not controlled.

 

[NJVetteGuy]

The master cylinder is attached to the body, and the rest of the brake system is on the frame. While minimal, there is flex between the body and frame. The minute flexing of the body/chassis needs to be allowed for, spreading the slight flex across a longer length of steel line that is coiled up is better than having the small surface area of a straight steel line to take all the flex.