scope:

This specification applies to all staff and contractors responsible for the management or installation of flash butt welding of rails.

This specification covers the requirements for flash butt welding in the following: situations:

a) Depot, to form welded rail strings using the following rail types:

I. 56E1 rail in grades R220, R260 and R350HT

II. 95RBH rail in grades R220, R260 and R350HT

III. Section 75 conductor rail.

b) Mobile (i.e. on-site), using the following rail types:

I. 56E1 rail in grades R220, R260 and R350HT

II. 95RBH rail in grades R220, R260 and R350HT

III. Section 75 conductor rail.

c) Welding of leg-ends to cast crossings, using 56E1 rail in grade R260.

Notes:

(1) The rail grades listed above are defined in EN 13674-1; other grades may be introduced following current trials

(2) Although grade R220 is included in the scope of this specification, it is unlikely that there will be a need to weld it in a depot situation as it is no longer purchased;

(3) The conductor rail listed above is defined in BS 7865;

(4) The requirements in this specification regarding Section 75 conductor rail may be applied to Section 65 conductor rail in the event that that rail is to be welded.

This specification covers the entire flash butt welding process, i.e.

a) approval of welding contractor or organization

b) procedure and machine approval

c) approval of other profiles and grades following procedure and machine approval

d) production welding

e) production weld testing and acceptance criteria

f) weld identification and records.

Purpose

This specification sets out the requirements for flash butt welded rail joints for installation in the LU infrastructure.