Specifications:
The document describes the NORIS Bauform 230, a welded sight glass valve with weld-neck flanges. These valves are suitable for integration into tanks, pipes, and vessels, and are compatible with both fluids and gases. They are particularly designed for custom, one-off applications.

Options:
The valves can be customized for any pipe diameter, nominal pressure, and material requirements.

Materials:
- Butt weld pipe ends and covers are available in WN 1.4571/1.4541 or C-Steel.
- Glass options include Borosilicate glass (DIN 7080) and Soda lime glass (DIN 8902).
- Gaskets are non-asbestos, with other materials available upon request.

Ordering Example:
An example order for a sight flow fitting Bauform 230 includes specifications such as WN 1.4571, Borosilicate glass DIN 7080-16 bar, and DN 50.

Dimensions:
The document provides a table of dimensions for various sizes, detailing visibility diameter (∅ D), size DN, and other relevant measurements (A, B, d) for sizes ranging from DN 40 to DN 200.

Example of Use:
The document includes an example of how these sight glass valves can be utilized in practical applications.