Questions re. Tensorex

[McRhu]

A couple of questions if I may...

The 'underbridge' or tunnel type fibreglass arms... Have they fallen out of favour in current OLE practice? And harking back to a point in one of the earlier replies... the 'spanwire' assemblies in MK III: what was the point in having the steelwork registered in place by a wire rather than just sticking with the |/ type 'triangle' as used in Mk I and Mk II? It looked nice (to my eye) but surely more difficult to install and maintain.

 

[59CosG95]

A couple of questions if I may...

The 'underbridge' or tunnel type fibreglass arms... Have they fallen out of favour in current OLE practice? And harking back to a point in one of the earlier replies... the 'spanwire' assemblies in MK III: what was the point in having the steelwork registered in place by a wire rather than just sticking with the |/ type 'triangle' as used in Mk I and Mk II? It looked nice (to my eye) but surely more difficult to install and maintain.

The fibreglass arms are very much still used - some have been installed on the Barrhead scheme very recently.

As for the MkI vs MkIII portal registrations, I've attached a small (very crude!) sketch below:
Essentially, any across-track adjustment of the registrations (for stagger correction etc.) was harder on the MkI style (A) as you had to move the vertical tube and the diagonal one.
As a result that style of registration is normally reserved for lower-speed, fixed-tension areas e.g. Birmingham New Street.

The MkIII style (B) is more of a 'one size fits all' registration.

 

[McRhu]

The fibreglass arms are very much still used - some have been installed on the Barrhead scheme very recently.

As for the MkI vs MkIII portal registrations, I've attached a small (very crude!) sketch below:
Essentially, any across-track adjustment of the registrations (for stagger correction etc.) was harder on the MkI style (A) as you had to move the vertical tube and the diagonal one.
As a result that style of registration is normally reserved for lower-speed, fixed-tension areas e.g. Birmingham New Street.

The MkIII style (B) is more of a 'one size fits all' registration.

Thank you very much for answering both of these questions. As regards the fibreglass arms, for some reason I had thought that they were only used very reluctantly now. Is there a restricted speed under these given that the lift characteristics must be very different from regular arms?

 

[WiredUp]

125mph.

 

[McRhu]

125mph.

Thank you very much. As far as I can make out (from a civvy's eye-level view) they don't seem to have a vertical hinge to allow lift. Still 125mph is a higher speed than I thought: I'd reckoned maybe 110.

 

[Zerohero]

Fascinasting info - thank you.
Is there a big difference in the plant needed to install a tensorex vs a BWA? i.e. cranes or standard MEWPS or scaffolds etc? Are tensorexes easier and thus faster to install?

Easier and Faster, Yes. Also very easy to set up to the temperature, although in my experience it is useful to read the installation manual in full before hand. It makes everything very clear.
Tensorex is also fit and forget. Very low maintenance, visual only. Whereas the BWA's have to be constantly maintained and adjusted.

 

[mr_moo]

Brilliant and useful info - thank you.