Longitudinal sight glass fitting type 337 PN 25 for welding in or on

Material: Base flange and cover flange: RSt 37-2, H II, C 22.8, P250GH, P265GH, 1.4306 (F304L), 1.4404 (F316L), 1.4462 Duplex (F51), 14539 (Alloy 904 L), 1.4541 (F321) , 1.4571 (F316Ti) or according to customer specifications Sight glass:  borosilicate glass acc. to DIN 7080 Soda-lime glass acc. to DIN 8902 Seal:  Klingersil or as desired Screws:  A4-70 Shape:  according to DIN 28120 Nominal size: DN25 - DN250 Nominal pressure:  PN 10/16  (depending on size and material composition) Temperature:  with soda lime glass up to max. 150 ° C with borosilicate glass up to max. 280 ° C  with borosilicate & mica shield up to 320 ° C Higher operating temperatures on request Options:  Optional versions are possible.   Special construction/options: With wiper blades SWI or SWII With spray nozzle SV1 Double glass Double Glass with heating element With LED or halogen lights, ATEX certification available With protective coating, variant B of DIN 28120 With O-Ring seal High Temperature Version with quartz window Impact protection plexiglass shield More special constructions available on request   DN Da Di h1 h2 s kg Nm 25 115 48 16 25 10 2,9 30 40 150 65 16 30 12 5,0 55 50 165 80 16 30 15 6,0 55 80 200 100 20 30 20 10,3 55 100 220 125 22 30 25 11,5 55 125 250 150 25 30 25 15,2 64 150 285 175 30 36 30 23,5 107 200[1] 340 225 35 36 30 30,7 125 250[1] (similar to DIN) 395 280 40 40 45 44,6 107   [1] PN 10 only   Use our 360° 3D view to get a perfect allround look at our product. Our round sight glasses type 320 are welded on or in a container wall to allow for observation or illumination of the inside of the container. A sight glass made of chemically highly resistant borosilicate glass DIN7080 is clamped between two high-quality stainless steel flanges and proven quality seals.  Beyond the definitions of DIN 28120, we also offer type 320 in special sizes of DN 250 and DN 300. These sizes, not specified in the standard, have also been constructed in accordance with DIN 28120.  Our sight glasses type 320 are made from high-quality stainless steel 1.4571 (316Ti), which our customers have appreciated for years. The glass material used is the tried-and-tested borosilicate glass according to DIN 7080 (or according to customer specifications).  The sealing of the fitting is done with flat seals tailored to your needs from a comprehensive range of materials. In addition to the common fiber seals, this also offers more demanding materials such as PTFE (Teflon®), NBR, novaphit® MST-XP, KlingerSil® C4400, and many other brand seals. If the maximum operating temperature of borosilicate glass DIN 7080 does not meet your requirements, or if the process conditions pose a problem even for the highly resistant borosilicate glass, a mica protection disk specially adapted for the fitting offers additional protection against temperature and steam. FEP or Halar® coatings additionally protect the borosilicate glass from aggressive chemicals or alkalis. Like other sight glass fittings, type 320 can be equipped upon request with sight glass wiper type SGW and SWII, spray devices SVI, or lights.

  Type A Type B Type H [bar] [°C] [bar] [°C] [bar] [°C] For soft environment,  not affecting aggressive on the glass ie. oils, hydrocarbons, etc. 400 120 265 120 300 120 150 400 180 400 200 400 0 - 10 430 0 - 10 430 0 - 10 430 For aggressive environment acting on the glass, eg. saturated steam, hot water, alkalis 35 243 35 243 42 253     Dimensions: Size TYPE A TYPE B TYPE H L W H L W H L W H 0 95 30 17 95 34 17 - - - I 115 30 17 115 34 17 115 34 22 II 140 30 17 140 34 17 140 34 22 III 165 30 17 165 34 17 165 34 22 IV 190 30 17 190 34 17 190 34 22 V 220 30 17 220 34 17 220 34 22 VI 250 30 17 250 34 17 250 34 22 VII 280 30 17 280 34 17 280 34 22 VIII 320 30 17 320 34 17 320 34 22 IX 340 30 17 340 34 17 340 34 22 X - - - 370 34 17 - - -   Reflex level gauge glasses offered by us are made by a recognized, global companies like Klinger, Maxos, Spectraglass of high-quality borosilicate("extra hard") or aluminosilicate glasses. Glass in the production process is subjected to a polishing and toughening. This results in products characterized by high mechanical strength and high resistance to alkalis, acids and condensates. In the production process is conducted constant and precise control of transparency and the dimensions of manufactured glass. Reflex gauge glasses  are used to read the liquid level directly or with the use of CCTV (industrial television). In this type of glass on the chamber side (medium side) are imprinted longitudinal grooves (3 or 4), which walls are angled to each other at an angle of 90˚. Squeezing process causes the formation of grooves. On the surface of the grooves creates extremely smooth and hard glass layer, very resistant to the environment. With the grooving increases the angle of refraction which makes the visibility of the liquid level is much better than when using smooth glass. For reflective glass does not apply mica shields. Reflex glasses may be used in pressure up to 35 bar. In this area are sufficiently resistant to the environment. The reading is clear and contrast. In the case of factors other than steam reflex glasses may be used up to 400 bar or 400˚C. Depending on the width and thickness there are three basic types of transparent level gauge glasses: type A - width 30 mm, thickness 17 mm type B - width 34 mm, thickness 17 mm type H - width 34 mm, thickness 22 mm In addition, the occasionally encountered also: Type C - width of 20 mm, thickness 12 mm Type D - width 25 mm, thickness 15 mm Reflex level gauge glasses are supplied in sets with gaskets or separately. We offer transparent glass meet the following standards: ÖNORM M 7354 (Austrian standard) DIN 7081 (German standard) JIS B 8211 (Japanese standard) ÖMV-Spez. H 2009 (factory standard of the Austrian petrochemical concern ÖMV-AG, Vienna) MIL-G-16356 D (regulations the US Navy) Esso Eng. Spec. 123 (Esso Research and Engineering Co. - New Jersey) S.O.D. Spec. 123 (Standard Oil Development Company - New Jersey) BS 3463 (British Standard) Note: transparent level gauge glasses are supplied in sets with gaskets or separately. If you can not find the size - please contact us.   While every attempt has been made to verify the source of the information, no responsibility is accepted for accuracy of data.

    Type A Type B Type H Type TA 28 3) [bar] [°C] [bar] [°C] [bar] [°C] [bar] [°C] For soft environment,  not affecting aggressive on the glass ie. oils, hydrocarbons, etc. 240 120 290 120 340 120 - - 160 400 800 400 230 400 - - 0 - 10 430 0 - 10 430 0 - 10 430 - - For aggressive environment acting on the glass, eg. saturated steam, hot water, alkalis 35 1) 243 35 1) 243 42 1) 253 120 2) 324 70 300 85 300 85 300 180 356   1) For steam pressures above 35 bar is recommended to use mica shields.2) For steam pressures above 120 bar can be used only glasses TA-28-I.3) Glass type TA 28 can be used only with mica shields.   Dimensions:   Size TYPE A TYPE B TYPE H TYPE TA 28 L W H L W H L W H L W H I 115 30 17 115 34 17 - - - 113 27,6 16,8 II 140 30 17 140 34 17 140 34 22 - - - III 165 30 17 165 34 17 165 34 22 163 27,6 16,8 IV 190 30 17 190 34 17 190 34 22 188 27,6 16,8 V 220 30 17 220 34 17 220 34 22 218 27,6 16,8 VI 250 30 17 250 34 17 250 34 22 248 27,6 16,8 VII 280 30 17 280 34 17 280 34 22 278 27,6 16,8 VIII 320 30 17 320 34 17 320 34 22 318 27,6 16,8 IX 340 30 17 340 34 17 340 34 22 338 27,6 16,8 X - - - 370 34 17 - - - - - -   Note: transparent level gauge glasses are supplied in sets with gaskets and mica shields or separately. If you can not find the size - please contact us.   While every attempt has been made to verify the source of the information, no responsibility is accepted for accuracy of data. Transparent level gauge glasses offered by us are made by a recognized, global companies like Klinger, Maxos, Spectraglass of high-quality borosilicate ("extra hard") or aluminosilicateglasses. Glass in the production process is subjected to a two-sided polishing and toughening. This results in products characterized by high mechanical strength and high resistance to alkalis, acids and condensates. In the production process is conducted constant and precise control of transparency and the dimensions of manufactured glass. Transparent (smooth) level gauge glasses  are used to read the liquid level directly or with the use of CCTV (industrial television). They can be (type TA 28) used up to 180 bar / 356°C for aggressive environments affecting (interacting) the glass (eg. saturated steam, hot water, alkalis) and up to 300 bar / 400°C for soft environments. Glass must be protected from the medium side through the mica shields. They are especially recommended for environments contaminated, viscous and highly corrosive. Depending on the width and thickness there are four basic types of transparent level gauge glasses: type A - width 30 mm, thickness 17 mm type B - width 34 mm, thickness 17 mm type H - width 34 mm, thickness 22 mm type TA 28 - width of 27.6 mm, 16.8 mm In addition, the occasionally encountered also: Type C - width of 20 mm, thickness 12 mm Type D - width 25 mm, thickness 15 mm Transparent level gauge glasses are  supplied in sets with gaskets and mica shields or separately. The set, packaged in a common box, consists of: box set of washers  gasket mica shield for the media side mica shield for the place of observation(with a hole Φ ca. 1 mm) installation guide   In all TA-28 sets, soft washers and protective washers are made from graphite foil. In set TA-28-I gasket is made from graphite laminate KlingerGraphite type SLS (see desc. here), but for sets TA-28-III .. TA-28-IX KlingerGraphite type PSM is used (see desc. here). In sets type A, B, H all washers are made from KlingerSil plate type C-4430 (see desc. here), but gaskets are made from graphite laminate KlingerGraphite type SLS (see desc. here).   It is good to know, that the role of the mica shield installed on the outside (ie, on the side of the viewer) is to reduce the thermal shock to which gauge glass is exposed, working on the one hand, in an environment of high temperature (steam, hot water), and on the other, with a low (room) temperature environment. Outer mica shield helps to a longer faultless operation of the set. The hole made in the shield, protects against moisture staying between the glass and mica while mounting assembly and relieves pressure above and below the shield during normal operation. box: set of elements: installation guide:   We offer transparent glass meet the following standards: ÖNORM M 7354 (Austrian standard) DIN 7081 (German standard) JIS B 8211 (Japanese standard) ÖMV-Spez. H 2009 (Austrian factory standard of the petrochemical concern ÖMV-AG, Vienna) MIL-G-16356 D (regulations the US Navy) Esso Eng. Spec. 123 (Esso Research and Engineering Co. - New Jersey) S.O.D. Spec. 123 (Standard Oil Development Company - New Jersey) BS 3463 (British Standard) We also provide glass unusual: manufactured according to individual customer technical requirements, custom sizes and custom shapes.

Borosilicate glass 3.3 is one of the most commonly used and well-known types of heat resistant glass. Its high silica content and significant boron oxide doping make it exceptionally stable. The material can be milled, drilled, ground, and toughened without losing its structural integrity. These characteristics, combined with its borosilicate glass strength, make it suitable for both industrial and scientific uses. This type of boro glass performs reliably at elevated temperatures and is thermally stable up to 450 °C under continuous use. Its borosilicate glass temperature stability is a primary reason why it is frequently selected for laboratory setups and chemical reactors. Additionally, borosilicate glass 3.3 maintains excellent mechanical strength even in low-temperature conditions, with operational capability down to -196 °C, making it compatible with cryogenic substances like liquid nitrogen. For optimal safety, the temperature difference during thawing should not exceed 100 K; typically, operation down to -70 °C is recommended. Thanks to its outstanding chemical resistance, this borosilicate glassware is impervious to water, acids, alkalis, and most organic solvents. As such, it is extensively used in pharmaceutical manufacturing, scientific research, and chemical processing plants. The borosilicate glass properties of type 3.3 also make it a material of choice for borosilicate glass dishes, beakers, flasks, and other laboratory vessels. Suprax 8488, Pyrex, Boronorm & Borofloat Other types of borosilicate glass, such as Suprax 8488, Pyrex, and Boronorm, offer comparable borosilicate glass hardness and resistance to chemical and thermal stresses. Suprax 8488 is known for its consistency and is often used in technical lighting and optical applications. Pyrex, a widely recognized brand name, is commonly found in consumer borosilicate glass products like cookware and bakeware. These borosilicate glass dishes resist staining, cracking, and thermal deformation, making them ideal for use in ovens and microwave environments. Borofloat is another premium borosilicate glass variant designed for optical, display, and semiconductor applications. Its exceptionally smooth surface and excellent flatness, combined with its inherent borosilicate glass strength, make it indispensable in high-tech industries. Whether used in analytical instruments or microelectronics, Borofloat ensures consistent performance under stress. Applications of borosilicate glass The variety of borosilicate glass applications is as vast as its properties. It is widely used in: Laboratory borosilicate glassware (beakers, test tubes, measuring cylinders) Domestic borosilicate glass products (bakeware, cookware, coffee carafes) Pharmaceutical containers (vials, ampoules) Chemical processing equipment (reactors, pipelines) Optical components (lenses, filters) High-intensity lighting systems (projector lamps, automotive bulbs) Solar energy systems (glass tubing, photovoltaic module covers) Display technology (substrates for TFT and OLED displays) The heat resistance of glass in these applications is crucial for maintaining dimensional stability and ensuring longevity. For instance, borosilicate glass dishes used in kitchens can transition directly from freezers to ovens without risk of breakage due to the material’s thermal shock resistance. Why choose borosilicate glass? To summarize, borosilicate glass combines chemical inertness, high mechanical strength, and remarkable temperature resistance, making it one of the most versatile materials available. Its hardness, clarity, and processability further enhance its desirability across numerous industries. Whether you are selecting materials for a high-performance optical lens, a laboratory flask, or a heat-resistant baking dish, borosilicate glass delivers outstanding performance. We supply a full range of borosilicate glassware and custom borosilicate glass products tailored to your specific needs. With several types of borosilicate glass available, including borosilicate glass 3.3, Suprax, Borofloat, and Pyrex, our product line meets the highest standards in modern engineering and design. Composition SiO2  80 % B2O3  13 % Na2O  4 % Al2O3  2 % K2O  1 %   Standard thicknesses and tolerances Thickness Tolerance Thickness Tolerance 0,70 mm ±0,1 7,5 mm ±0,3 1,10 mm ±0,1 8,0 mm ±0,3 1,75 mm ±0,2 9,0 mm ±0,3 2,00 mm ±0,2 13,0 mm ±0,5 2,25 mm ±0,2 15,0 mm ±0,5 2,75 mm ±0,2 16,0 mm ±0,5 3,30 mm ±0,2 17,0 mm ±0,5 5,00 mm ±0,2 18,0 mm ±0,5 5,50 mm ±0,2 19,0 mm ±0,5 6,50 mm ±0,2 21,0 mm ±0,7   Properties: Density (@ 20 °C) 2 230 kg/m3 Bending strength 160 N/mm2 Surface compressive stress 100 N/mm2 Young’s modulus  64 GPa Poisson’s ratio 0,2 Hardness 5.5 Mohs, (470 Knopp, 580 Vickers) Thermal conductivity 1,2 W/(m K) Specific Heat 0,83 kJ/(kg K) Coefficient of linear expansion 3,3 ±0,1 * 10 -6 °C Index of refraction (@ 380 - 780 nm) 1,48  Softening point 815 °C Annealing Point 560 °C Max. working temperature: Non-tempered glass    - long term 450 °C  - temporary(< 10h) 500 °C Tempered glass    - long term 280 °C  - temporary(< 10h) 500 °C   Chemical properties: Hydrolytic Resistance   Acc.  ISO 719 (w 98 °C): class HGB 1    Acc.  ISO 720 (w 121 °C): class HGA 1  Alkali resistance   Acc. DIN 52 322 (ISO 695): class A2 Acid resistance   Acc. DIN 12 116: class 1 Electrical properties Volume resistance    at 25°C = 6.6 x 1013 Ω cm    at 300°C = 1.4 x 106 Ω cm Dielectric properties Electric Volume Resistivity         8,6 x 1013 Ωcm (at   25 °C)   1.4 x 106   Ωcm (at 300 °C) Dielectric dissipation fraction   38  10-4 (at 1 MHz, 20 °C) Dielectric constant εr   4.6 (at 1 MHz, 20 °C)   Optical properties Index of Refraction Spectral Transmission    λ = 587,6 nm nD = 1,4724    λ = 480,0 nm nF = 1,4782    λ = 546,0 nm nE = 1,4740    λ = 644,0 nm nC = 1,4701    Borosilicate glass 4.3 SiO2  78 % B2O3  10% Na2O  7 % Al2O3  3% ZrO2  2 %   Properties: Density (@ 25  °C) 2 280 kg/m3 Flexural strength 25 MPa Modulus of elasticity (Young’s) 67 GPa Poisson’s ratio 0,20 Thermal conductivity (@ 90 °C) 1,2 W/(m K) Specific heat 0,83 kJ/(kg K) Coefficient of linear expansion  (@ 20 °C - 300 °C) 4,3  * 10 -6 °C Index of Refraction (λ=587,6 nm) 1,484  Softening point 810 °C Annealing point 580 °C Glass temperature for density dPas 1013,0    560 °C10 7,6    800°C10 4,0   1200°C Working temperature:  - maximum 500 °C  - in a heavy duty conditions 280 °C   Chemical properties   Hydrolytic Resistance   Acc.   ISO 719 (@ 98 °C): class HGB 1    Acc.   ISO 720 (@ 121 °C): class HGA 1  Alkali resistance   Acc. DIN 52 322 (acc. ISO 695): class A2 Acid resistance   Acc. DIN 1776: class 1 Electrical properties Volume resistance    @ 25°C = 6.6 x 1013 Ω cm    @ 300°C = 1.4 x 106 Ω cm Dielectric properties @ 25° C and 1 MHz:    Dielectric constant εr=4,6    Dielectric loss factor tgδ =1,4x10-2   Optical properties Index of Refraction Spectral Transmission    λ = 587,6 nm nD = 1,4816    λ = 480,0 nm nF = 1,4869    λ = 546,0 nm nE = 1,4831    λ = 644,0 nm nC = 1,4802      While every attempt has been made to verify the source of the information, no responsibility is accepted for accuracy of data. In this text you will learn about borosilicate glass: properties, strength, thermal and chemical resistance, types, and applications in laboratory, industrial, optical, and domestic environments. Properties and applications of borosilicate glass Borosilicate glass is a specialized type of glass that contains significant amounts of silica (SiO₂) and boron trioxide (B₂O₃), making it highly resistant to thermal shock and chemical corrosion. Known for its durability, clarity, and stability under temperature fluctuations, borosilicate glass is widely used in laboratory, industrial, and domestic applications. Often referred to as boro glass, this material exhibits unique performance characteristics that set it apart from conventional soda-lime glass. One of the key properties of borosilicate glass is its exceptional resistance to temperature changes. This heat resistant glass can withstand both extremely high and low temperatures, making it suitable for demanding environments. The borosilicate glass temperature resistance allows it to endure up to 450 °C during long-term use and down to -196 °C when in contact with substances like liquid nitrogen. These attributes are a result of its low coefficient of thermal expansion, which ensures the glass does not crack or deform when exposed to rapid temperature changes. Another significant feature is the borosilicate glass strength and durability under mechanical and thermal stress. The typical hardness of borosilicate glass is rated at 5.5 on the Mohs scale, with corresponding values of 470 on the Knoop scale and 580 on the Vickers hardness test. These measures confirm the high borosilicate glass hardness, making it ideal for situations that demand both precision and resilience. The versatility of borosilicate glass arises from the ability to modify its chemical composition by incorporating various metal oxides. These variations result in a broad range of borosilicate glass products, each tailored for specific applications. The boron oxide content in the glass batch—i.e., the mix of raw materials used in the production process—plays a crucial role in defining not only the borosilicate glass properties, but also the behavior of the molten glass during manufacturing. At our facility, we offer several types of borosilicate glass, including: Borosilicate glass 3.3 (DIN 7080) Borosilicate glass 4.3 Suprax 8488 Pyrex Boronorm Borofloat Each of these borosilicate glass types features unique compositions and is suited for various borosilicate glass applications, from laboratory glassware and cookware to high-performance optics and chemical equipment. To work in an environment of steam and hydrostatic applications we offer borosilicate glass 4.3. Resistance to chemicals and thermal expansion permit the use of a high level of hardening, so that the glass are characterized by high resistance to thermal shock. Is suitable for operation at low temperatures. Can withstand the temperature to about -196 °C (is suitable for use in contact with liquid nitrogen). During thawing ensure that the temperature difference does not exceed 100 K. In general is recommended for use down to -70 °C.

Material: Base and top frame:  1.4571; 1.4404, 1.4462, RSt 37-2 / H II / Other materials on request Screws:  A4-70 Seals: depending on the application Glass:  Reflections -or- Transparent glass according to DIN 7081 or DIN 8903 Shape:  Rectangular Sight Glass as level indicator for visual inspection of tanks, boilers and silos Nominal size: size from 140 mm up to 1000 mm  Other sizes on request Nominal pressure: PN 16 or PN 40 For operating pressures up to max. 35 bar depending on the model Temperature:  temperature: 100 ° C or 243 ° C depending on the glass and seal selection. Special Feature: Lloyd’s Register Design Approval available Options: Optional versions are possible. Gasket selection: PTFE (200°C) FKM (200°C) NBR (100°C) C4400 (150°C) Silicone (200°C) EPDM (140°C) Graphite (320°C) Installation instructions: After welding in the base flange, check whether the sealing surfaces have warped! If necessary, rework must be carried out. The operating pressure does not apply to the base frame, which must be checked together with the pressure device according to AD data sheet B9! BL = overall length / SL = visible length BL SL Concealed view Kg(16 bar) Kg(35 bar) 140 79 0 2,8 3,4 170 124 0 3,2 4,0 220 174 0 4,0 5,0 250 204 0 4,6 5,7 300 264 0 5,3 6,7 310 264 0 5,6 7,0 350 304 0 6,3 7,8 370 324 0 6,6 8,2 400 354 0 7, 8,9 500 454 1x46 9,1 11,4 600 574 1x46 10,7 13,4 620 574 1x46 11,1 13,9 700 654 1x46 12,5 15,7 740 694 1x46 13,2 16,5 800 74 1x46 14,2 17,8 930 884 2x46 16,7 20,9 1000 954 3x46 18,2 22,8   The ACI sight glass of type 330 is used for reliable observation of the liquid level in closed containers such as boilers, tanks, or silos. It is a rectangular vertical sight glass that can be either welded into the container wall or attached by welding. The fitting is equipped with a sight glass plate made of high-quality borosilicate glass according to DIN 7081 (or comparable). This is securely framed between gaskets and tightly screwed to ensure permanent sealing and high pressure resistance. Standardly, the sight glass type 330 is made of stainless steel 1.4571 (316Ti) – a material characterized by high corrosion resistance and durability. Upon request, the design is also available in many other materials, suitable for specific requirements and applications. The sealing of the fitting is done with flat gaskets tailored to your needs from an extensive range of materials. In addition to the common fiber material gaskets, more sophisticated materials such as PTFE (Teflon®), NBR, novaphit® MST-XP, KlingerSil® C4400, and many other branded gaskets are also available. If the maximum operating temperature of borosilicate glass according to DIN 7081 does not meet your requirements, or if the process conditions pose a problem even for the highly resistant borosilicate glass, a mica protection disc specially adapted for the fitting provides additional protection against temperature and steam. FEP or Halar® coatings also additionally protect the borosilicate glass from aggressive chemicals or alkaline solutions. For applications in poorly lit containers, the use of a reflex sight glass according to DIN 7081 (or comparable) is recommended. These glasses are embedded with special prism structures that break and reflect the incoming light – thus, the filling level can be recognized much better. If, however, the container is well-lit, the medium is very clear, or if the color of the medium should remain visible, a transparent sight glass is the better choice. It allows for an unaltered view and precise optical control of the contents. Important note: Reflex sight glasses cannot be combined with mica discs and coatings, as the protective mica layer prevents the light refraction necessary for reflection. Transparent glasses, on the other hand, can easily be equipped with mica discs, FEP, or Halar® coatings, which is particularly recommended for protection of the glass in the case of aggressive media or high temperatures.

Material: Base flange:  1.4571, 1.4404, 1.4435, 1.4462, 1.4539, 1.4541, 2.4602, 2.4610, P265GH, Alloy , Super Duplex Cover flange:  1.4571, 1.4404, 1.4435, 1.4462, 1.4539, 1.4541, 2.4602, 2.4610, P265GH, Alloy , Super Duplex Bolts:  DIN 912, A4-70, or special materials Glass plates:  Borosilicate glass acc DIN 7081 Soda lime glass acc. To DIN 8903 Sealing: Universal Quality (aramid fiber) (Other materials available) Shape: oval longitudinal sightglass for insertion or welding Nominal size: 250 - 670 mm Nominal pressure: Operating pressures up to 6 bar (Vacuum version available on request)   Installation length View KG 250 180 5,7 310 240 7,0 370 300 8,4 430 360 10,2 490 420 11,0 550 480 12,4 610 400 13,7 670 600 15,1   Temperature: 100°C or 243°C depending on glass and gasket selection. Gasket selection: PTFE (200°C) FKM (200°C) NBR (100°C) C4400 (150°C) Silicone (200°C) EPDM (140°C) Graphite (280°C) Special feature: A Lloyd's Register design appraisal is available. Take advantage of our 360 degree 3D view for a perfect all-round view of our product.   While every attempt has been made to verify the source of the information, no responsibility is accepted for accuracy of data. The ACI sight glass type 336 is a lightweight version that offers a significantly enlarged viewing opening compared to our type 330 at relatively low operating pressure up to max. 6 barg. This design combines the functions of our round sight glasses like type 318 and our level indicators for container wall mounting type 330. The fitting is equipped with a sight glass plate made of high-quality borosilicate glass similar to DIN 7081 (or according to customer specifications). This is securely framed between seals and tightly screwed to ensure permanent tightness and high pressure resistance. Standardly, the sight glass type 336 is made of stainless steel 1.4571 (316Ti) - a material that is characterized by high corrosion resistance and durability. On request, the design is also available in many other materials, suitable for specific requirements and applications. The sealing of the fitting is done with flat seals adapted to your needs from a wide range of materials. In addition to the common fiber material seals, it also offers more advanced materials, such as PTFE (Teflon®), NBR, novaphit® MST-XP, KlingerSil® C4400, and many other branded seals. If the maximum application temperature of borosilicate glass DIN 7081 does not meet your requirements or if the process conditions pose a problem even for the highly resistant borosilicate glass, a mica protective disc specially adapted for the fitting provides additional protection against temperature and steam. FEP or Halar® coatings additionally protect the borosilicate glass against aggressive chemicals or caustics.