4　Piping Layout for Piperacks

4.1　General Requirements

4.1.1　Orientation and elevation of piping to/from process plants which is installed on piperacks shall well coordinate with that of piperacks for adjacent process plants or plant-wide piperacks.

4.1.2　For process plants to be constructed in phases，the piping layout shall be designed according to plant phased construction requirements.

4.1.3　Interconnection piperacks or pipe sleepers（including culver for pipe crossing）shall have a margin of 10%-30% reserved with a consideration of its load-bearing capacity.

ISBL piperacks should have a margin of 10%-20% reserved with a consideration of，its load-bearing capacity.