This part of YC/T 234 specifies the type and size of process holes for thin flat sound-absorbing adhesive bonded panels. This section applies to the design and manufacture of thin flat sound-absorbing adhesive bonded panels.
YC/T 234.3-2007 history
2007YC/T 234.3-2007 Structural main factors for sheet metal stamping parts- Part 3: Sheet added absorb sound glue