Sdd23 diesel locomotive is a DC drive trunk line passenger and freight locomotive developed for the Pakistani Broad Gauge Railway. The locomotive adopts a single-cab outdoor corridor body structure, and the walking part is a bogie drawn by secondary high round springs and low inclined tie rods. Equipped with CAT C175-16 diesel engine, main and auxiliary coaxial generators, auxiliary AC drive system and microcomputer control system, it has the functions of double machine reconnection and resistance braking. The locomotive has the characteristics of adapting to high temperature, strong wind, sandy dust environment and high-speed operation in complex environments.
CKD7B diesel locomotive is a mainline diesel locomotive exported to Myanmar by CRRC Dalian Locomotive and Rolling Stock Co., Ltd. The locomotive adopts CAT3516B diesel engine and ADLC microcomputer control device produced by Caterpillar in the United States. It has the functions of constant power excitation control (directly controlling the excitation of the exciter), auxiliary power generation control, resistance braking control, rotation adhesion prevention and control, etc. The braking method adopts air braking and resistance braking.