The Drawing Block Types folder of the Domain Explorer enables you to navigate to a CAD drawing block types and a drawing block in a graphical way resembling the Windows Explorer. The Drawing Block Types folder contains all the blocks defined in the current <plant>. You organize your block in block type folders. The blocks that you define become available for association with instruments, loops, or hook-ups but you do make any associations in the Drawing Block Types folder. CAD drawing blocks appear in the Domain Explorer because it is only possible to define blocks at the highest plant hierarchy level.
You can expand or collapse the levels to view the existing items. To perform an action, right-click the Drawing Block Types folder, a specific block type or a block, and then select a command. The software uses various icons beside a folder or item to indicate the status of a folder or an item, for example a view-only item, a claimed item, an item that belongs to As-Built, and so forth. For the full list of the item indicators, see Item Status Indicators in the Domain Explorer. For a detailed explanation of the tree view, see Working with the Domain Explorer.
In the Drawing Block Types folder, the items appear in two levels, based on the relationship among them.
Level 1: Drawing Block Types
This is the highest level in the Drawing Block Types folder hierarchy. At this level, the software displays all the drawing block types that exist in the current domain and allows you to add general and instrument block types and manage block type properties.
The following drawing block types are available:
Border and Logo 
Shipped general block types that allow you to create logo and border blocks for all loop drawings or hook-up drawings. You cannot delete these block types.
User-defined general block type
A block type that allows you to create blocks you can use in all loop drawings in addition to the border and logo blocks. You can create as many user-defined general block types as you require by right-clicking the Drawing Block Types folder and selecting New > General Block Type. Blocks belonging to user-defined general block types cannot be assigned to hook-up drawings.
Loop Block 
A shipped block type that allows you to create blocks that you can associate with the loop numbers in the Loops folder of the Domain Explorer. The Loop Block folder is the only folder where you can create loop blocks. You can only associate one loop block per loop. You cannot delete the Loop Block folder.
Instrument block type 
A user-defined block type that allows you to create blocks that you can associate with the instrument tag numbers in the Loops folder of the Domain Explorer. You can create as many instrument block types as you require by right-clicking the Drawing Block Types folder and selecting New > Instrument Block Type.
Level 2: Drawing Blocks
CAD blocks appear under block types. Blocks do not contain child items. You can add new blocks or delete blocks that are not in use.
The following block icons are available:
Logo, border, or user-defined general blocks
Loop blocks
Instrument blocks