When did most 40’ steel reefers start to get built with the plug-doors as opposed to the older doors (like the ones on the older wood reefer cars)?
atsf started doing it around 1950 but regular doors were common up until the end of ice bunker cars. it can be hard to tell a plug door insulated box car form a reefer. i guess the ice hatches on the roof would be the give away. from my railroad experience, i would have to say that plug doors were more common on mechanical refrigerator cars than on icers.
grizlump
I believe the first Pacific Fruit Express reefers equipped non-experimentally with plug doors were class R-40-26 built in 1970. These were all-metal cars with overhead interior fans but were cooled with ice loaded from hatches at the roof ends.
Mark
1970 - a typographical error perhaps? According to PFE, 2nd Edition, the R-40-26s were delivered from July 1951 to May 1952. In 1970 PFE was taking delivery of the second order of R-70-20s, R-70-22s, and R-70-23s.
Ooops, I misinterpreted the wrong table. Page 163 of that book shows R-40-26s were built 1950-51, all 2000 of them.
Mark
Technically, a “regular” reefer door is a plug door also, it swings open rather than slides.
The PRR (among others) had sliding plug doors back in the 1880’s.
Ya the term “plug door” usually is used in reference to a plug door boxcar, which is an insulated boxcar which can be mechanically cooled down before being loaded, but has no icing or mechanical cooling mechanism of it’s own.
As industries moved from manual labor to the use of fork lifts, the 4 foot opening (PFE standard) and 5 foot doors proved problematic, attempts by PFE to address this consumer demand resulted in 1949 of the R-40-26 class with 6 foot youngstown sliding plug doors, over a thousand were constructed in company shops, but these were not the first massed produced examples, in 1946 PFE rebuilt numerous ancient R-40-10’s with the same youngstown door as the prototypes.
The R-40-26 were designed with removeable ice bunkers to permit full length lading when employed in refrigerated/dry ice or top-ice-only service, a design that proved wise upon the cessation of top icing in 1973 when the cars were stripped of their ice bunkers, roof hatches and formally reassigned to Top-ice-only or dry ice service.
Dave