Towards the end of the 1950s, the type 22 carriage started entering services with the Chinese railways.

In 1962, however, both the type 22 and 23 passenger cars received some minor revision, reducing the seating on the YZ23 to 120.

[2] In 1961, Changchun Railway Vehicles delivered a different design of the passenger car, also registered as type 23 to the southern regions of China.

These blueprints were passed on to Tangshan Locomotive in 1963,[1]: 121  which then modified the existing design by adding a counter and a refrigerator room, creating the CA23 car.

[6]: 103  Yet another unrelated design was created in 1966 by Tangshan Locomotive, with their CA23 car having air conditioning.