Sight Glass according to DIN 28120 pages
Sight Glass according to DIN 28120 PD 66326 GB 2002-02
Keep an Eye on Your Product
Application
The bolted sight glass is used for visual control of processes
inside vessels which typically are under high pressure and have
temperatures. The sight glass is used in chemical, pharmaceutical
and cosmetical industries as well as in dairies, breweries and
other food industries.
Standard Design
The sight glass consists of a base flange, a cover flange, gaskets,
a glass disc, nuts and studs. The sight glass is to be welded into
or onto vessel walls and it corresponds in its construction and
assembly to the dimensions and constructional guidelines of the
DIN specification 28120. The respect of the DIN prescriptions for
the flange thicknesses guarantees a distortion free location of the
sight glass disc in case of correct welding. The pressure resistance
of the glass disc is, of course, dependent on the care with
which the bolts and nuts are tightened (always working on
diametrically opposed pairs). For lubricated bolts, Ra = 0.1mm,
the recommended tightening torque values (in Nm) are indicated
in the table on page 2. The glass discs are made of borosilicateglass
to DIN 7080 which means that the maximum operating
temperature is 280°C. All steel parts available with material
certificate EN10204.
3.1B/AD-W2.
Technical Data
Max. product pressure: Max. 1000 kPa (10 bar)
Min. product pressure: Full vacuum.
Temperature range: -10°C to +140°C
(EPDM), (higher temperatures up
to 280°C with gaskets of Klingersil).
Fig. 1. Sight Glass DIN 28120.
Materials
Base flange: AISI 316L, material certificate 3.1B/AD-W2.
Cover flange: AISI 321, material certificate 3.1B/AD-W2.
Gaskets: Klingersil C4400 (cover side)/EPDM
(product side).
Glass disc: Borosilicate to DIN 7080, material certificate
2.2 (max. 280°C).
Bolts or studs: To DIN 938/934 in A2-70.