Tulip chair identification, KD mark on underside  

Hello, new to this forum and furniture refurbishment but a fan of design. 
Just picked up four chairs and a round table, white, tulip design. Chair shells are fibreglass, bases attract a magnet. Underside is a stenciled KD mark in the paint. I know there have been questions about this mark on other posts here but I didn’t see that the maker was identified in those situations. I understand there was a tulip chair manufacturer Krueger but have been unsuccessful in finding out if this could be their mark, plus the photos I have seen show a different pedestal attachment. I would like to identify the maker as I need to disassemble them and may need replacement swivel mechanism parts. Any help in identifying them or useful resources, or guidance for next steps would be very much appreciated!