For a leading chemical company, we were once again allowed to participate in a new project.
We were to offer a flow sight glass with flange connections according to DIN EN 1092-1, sealing surface form D (groove). Our customer specified the stainless and austenitic special steel 1.4539 as the material for the housing and the connecting flanges. The material 1.4539 (Alloy 904L) is characterized by its high molybdenum content and the addition of copper, and has a very low carbon content. This results in resistance to pitting, stress corrosion and intergranular corrosion.
In conjunction with the valid VdTÜV material sheet 421, we were even able to meet the material requirements according to AD2000 W2/W10. The DN 25 nominal size, in conjunction with the required material and the design pressure of 40 bar(g), made the selection very easy for us.
Since cast special materials are not economical for single-unit quantities, we decided to use the Type 520 flow sight glass. We usually do not use our Type 520 very often for low-pressure applications. However, due to its welded construction, the Type 520 is very flexible to adapt.
The sealing surface form as well as the desired total length can be flexibly adapted to the customer's requirements. Type 520 can be used at +280°C for up to 27.6 bar(g) according to the pressure and temperature classification in DIN EN 1092-1. In order to ensure reliable process monitoring even at the design pressure of 40 bar(g) (deviating depending on the operating temperature), we have equipped Type 520 with the proven borosilicate glass.
The sight glass plates were manufactured in accordance with the existing DIN 7080. In order to further increase the pressure stability and media resistance, the sight glass plates were protected with additional mica discs. Due to the aggressive medium and in combination with the high design temperature, we decided to use graphite gaskets. The high-pressure sight glass gaskets used, made of novaphit® MST-XP, can be used for operating pressures of up to 250 bar.
We offer the flow sight glass type 520 as standard from nominal size DN 15 up to nominal size DN 200. We are happy to offer deviating special sizes on request. We can cover a wide pressure range from PN 40 to PN 320 as standard. However, if you are facing more adverse operating conditions, please do not hesitate to contact us!
We are always working at high pressure to meet your requirements.