Continental Trade Sp. z o. o.


Flow sight glasses with double glazing type 531D


The ACI double-glazed flow sight glass type 531D is based on the same proven design as the Type 530 and is therefore also considerably lighter than comparable valves with cast housings. As with Type 530D, only high quality materials are used in a tightly controlled process from quotation to delivery to ensure that the fitting meets your requirements.

The double-glazed with opposing viewing windows of type 531D offer increased safety compared to single-glazing and allow the observation and illumination of the flowing medium. In the standard configuration they consist of proven borosilicate glass in accordance with the DIN 7080 standard. If these highly resistant glasses do not meet your requirements, we manufacture special glasses made of borosilicate glass in accordance with DIN 7080, quartz  or corundum or sapphire specially designed to meet your requirements. If an even higher level of safety is required, we also have sight glasses with safety double glazing such as type 586 in our product range.

Sealing is provided by quality gaskets from renowned suppliers, which we select according to the requirements of your individual application. Apart from the widely used fibre gaskets such as KlingerSIL C4400, we also use graphite gasket sheets with and without metal inserts, pure or expanded PTFE, or mica composite gaskets under extreme operating conditions.

Simply contact our team of experts with your requirements and let them advise you on the possibilities that our product range offers you for your plant!

See further below for detailed technical information and 3D animations.


Body made of: WN 1.4539, 1.4541, 1.4571, 1.4404, P235GH, P265GH and many more.


Glass plates:
- Borosilicate glass DIN 7080
- Soda lime glass DIN 8902
- quartz glass

graphite (other materials available)

straight flow sight glasses with welding ends

Nominal size: 
DN40- DN400

Nominal pressure:
PN10, PN16, PN25, PN40, PN63


280 ° C with borosilicate glass to DIN 7080
150 ° C with soda lime glass DIN 8902
up to 500 ° with quartz

Watch our animation video, here you can see the structure of our flow sight glass type 531D perfectly

Download data sheet.

While every attempt has been made to verify the source of the information, no responsibility is accepted for accuracy of data.

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