GBT 13681.2-2017 焊接六角法兰面螺母.pdf

ICS21.060.20J13．七：－＿－：．．．一：·：：通沁·..-.',＇，??,',','.,..，:＇sm,',',f--...,、...GB/T13681.2—2017代替GB/T13681.2...