dear all
thank you for your reply.
i use COMPRESS for the designing. but COMPRESS does not supply a method for BELLOW.
i also use PVElite to calculate the BELLOWS, but some steps do not meet APPENDIX 26.
i think the 'UG-29' rule maybe 'UG-28' which is mentioned in appendix 26-6.5.2, but how to determine the value La in UG-29? the total length of shell or only the bellow length? i don't know. it's very difficult to understand for me.