Bosch pump - external cold-start pipe?

[nametooshort]

On this photo, you can see a metal pipe that goes from item 1 (the cold-start enrichment solenoid?) to the top of the pump.

In my attempts to de-immobilize my Bosch pump, I accidentally crushed that pipe in a vice. when clamping the pump in the vice, to be honest I completely forgot the pipe was there, and as I was clamping the pump in the vice one of the jaws crushed that pipe.

My question is, what sort of pressure goes through that pipe? Is it a high-pressure pipe (like, the same as injector pressure), or is it a reasonably low-pressure pipe, with fuel only at 'transfer pump' pressure.

For what I understand about how diesel injector pumps work, basically there is a plunger on a cam that feed the injectors with very high pressure fuel. Every cycle, that plunger has to 'reload' with fresh fuel, and there is a valve which controls how much of a fuel charge the plunger receives. So the more open the valve is, the more fuel fills the plunger, and then the cam pushes the plunger which forces that fuel to the injector. This valve is connected to the throttle lever. Correct so far?

Then, there is a 'transfer pump', which is a separate subsystem, who's job is to suck fuel from the tank through the fuel lines, and to pressurize the fuel enough so it fills the plungers. The pressure this pump produces is not huge.

So, so I understand correctly, that the 'cold start' valve basically just adds a small bypass for the throttle lever? So rather then fuel having to go through the throttle valve, some fuel bypasses it through the cold start valve?

So, do i assume correctly that the fuel which is delivered through that little metal pipe is not at great pressure, and I could probably replace it with a flexible pipe of some sort (made out of small-bore high pressure fittings, such as found in turbo control plumbing etc), and it will be OK?

Or, did I completely not understand everything, and the fuel going through that pipe is actually at injector pressure, and has to have a steel pipe because it would burst anything else?

Thanks!

[CitroJim]

That pipe feeds fuel at transfer pressure to the timing device. Transfer pressure is that generated by the lift pump and is not huge. 7 or 8 bars I believe.