Sight glasses GN 7440 are equipped with a sight glass that is metal-fused to the body by a thermal process. As a result the liquid glass adapts precisely to the contour of the body. During cooling, the different coefficients of linear expansion of the two joining partners generate strong mechanical initial stress between the glass and metal.
This initial stress makes the sight glasses 100% leakproof and particularly resistant to dynamic pressures and high temperatures when used with liquid and gaseous media. Moreover, the site glass offers a high level of safety, as potential damage is indicated in advance by small cracks without breakage of the glass. The seal is embedded in a radial recess, and thus cannot be lost or squeezed out during tightening.
The recommended operating pressures are non-binding values and rule out any liability. The user must determine from case to case whether a product is suitable for the intended use. Environmental factors can influence the specified values.
Stainless steel AISI 316 L
Grooves melted into sight glass
Sight glass float-glass
Rubber FPM (Viton®) (identification no. 2)
Temperature resistant up to 180 °C
(without pressure load)
Copper (identification no. 3)
Temperature resistant up to 300 °C
(without pressure load)
If this article is new in our product range, it may happen that details concerning weight are as yet not listed. If you do need weight details, please contact our Sales Department! Phone+49 7723 6507 - 0
This article is RoHS-compliant in application of Annex III., which means it complies with EU Directive 2011/65/EU, including extension (2015/863/EU), for restricting the use of certain hazardous substances in electrical and electronic devices. The Directive regulates the use of hazardous substances in devices and components. The implementation in national law is summarily described with RoHS(Restriction of (the use of certain) hazardous substances).
Please note our order discounts.
With a total value (net) per order: from 175,00 € -> 10 % discount from 275,00 € -> 20 % discount from 375,00 € -> 30 % discount
Surcharge for small volume purchases: -> 15,00 Euro for value of goods less than 25,00 € -> 10,00 Euro for value of goods from 25,00 to 50,00 €
All prices in accordance with our price list No. 55, valid from 1 September 2022, plus VAT only valid for Germany.