GN 7440Stainless Steel Oil Sight Glasses

Seal FPM (Viton<sup>®</sup>)

AISI 316L, Temperature Resistant to 180 °C

Catalogue
d1
d2
max. operating pressure
(safety factor 5)
at -20 °C to 120 °C
in bar
d3
l1
l2
s
GN 7440-11-G3/8-A-2
11
G 3/8
80
22
8
7.5
20
22
GN 7440-11-M16x1,5-A-2
11
M 16 x 1.5
22
8
7.5
20
22
GN 7440-14-G1/2-A-2
14
G 1/2
80
26
8.5
7.5
23
30
GN 7440-14-M20x1,5-A-2
14
M 20 x 1.5
26
8.5
7.5
23
30
GN 7440-18-G3/4-A-2
18
G 3/4
80
32
9
8
30
52
GN 7440-18-M26x1,5-A-2
18
M 26 x 1.5
32
9
8
30
51
GN 7440-24-G1-A-2
24
G 1
80
40
11
8.5
36
82
GN 7440-24-M33x1,5-A-2
24
M 33 x 1.5
40
11
8.5
36
82
GN 7440-32-G11/4-A-2
32
G 1 1/4
40
50
12
9
46
130
GN 7440-32-M42x1,5-A-2
32
M 42 x 1.5
50
12
9
46
130

Type

  • Type A: with reflector grooves

Identification no.

  • No. 2: Seal FPM (Viton®)
  • No. 3: Seal copper

Body

Stainless steel AISI 316L

Contrast screen

Grooves melted into sight glass

Sight glass float-glass

  • Metal-fused
  • Shrink-fit

Seals

  • 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)

Stainless steel 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 particulary 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.

  • Seals of NBR or EPDM
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