Drawings
General arrangement drawings are issued for approval per order, against the confirmed configuration. They are not a catalogue item, because a GA drawing for a size and class you are not buying is of no use to anyone.
What a GA drawing must show
- Face-to-face or end-to-end dimension
- Overall height, open and closed
- Handwheel or actuator envelope and swing radius
- End preparation detail, dimensioned for the specified pipe schedule
- Weight
- Lifting point locations
- Body material and rating
- Required installation orientation, where it matters
- Flow direction, where the valve is unidirectional
Face-to-face compliance with ASME B16.10 does not guarantee the valve fits. Height, handwheel swing and weight are not standardised, and a compliant replacement can still foul a platform or exceed the existing supports.
Sectional arrangements
The drawings below are schematic sections showing the general construction of each valve type. They identify the parts referred to in the material tables on the product pages. They are not manufacturing drawings and are not to scale.
When the GA drawing is issued
After order and before manufacture, as an approval-stage deliverable. Approving it is the last cheap opportunity to catch an installation problem. Once the body is machined, a change to the envelope is a new valve.