Type 318V - PN2.5 (vacuum)

The method of sizing:   DiameterD [mm] Widths [mm] Pressure[bar] Notes 24 10 150 disc special size 30 12 150 disc special size 15 200 disc special size 31,6 12,75 150 disc special size   Aluminosilicate 33 14 150 disc special size 33,12 15,95   Aluminosilicate 34 17 200 disc special size   Aluminosilicate 35 7 25 disc special size 40 10 40 disc special size 12 50 disc special size 44 10 40 disc special size 12 50 disc special size 45 10 40 acc. DIN 7080 12 50 acc. DIN 7080 50 10 25 acc. DIN 7080 12 40 acc. DIN 7080 55 6,5 6 disc special size 10 25 disc special size 60 10 16 acc. DIN 7080 12 25 acc. DIN 7080 15 40 acc. DIN 7080 20 95 disc special size 63 8 8 disc special size 10 16 acc. DIN 7080 12 25 acc. DIN 7080 15 40 acc. DIN 7080 65 10 12 disc special size 15 40 disc special size 70 12 16 disc special size 15 25 disc special size 75 12 16 disc special size 80 10 10 disc special size 12 16 acc. DIN 7080 15 25 acc. DIN 7080 20 40 acc. DIN 7080 86 12 10 disc special size 90 10 8 disc special size 92 10 8 disc special size 94 12 10 disc special size 95 10 6 disc special size 15 16 disc special size 100 10 7 disc special size 12 10 disc special size 15 16 acc. DIN 7080 20 25 acc. DIN 7080 25 40 acc. DIN 7080 105 15 16 disc special size 110 12,5 10 disc special size 20 25 disc special size 113 15 10 disc special size 115 15 10 disc special size 120 10 4 disc special size 15 10 disc special size 18 16 disc special size 125 15 10 acc. DIN 7080 20 16 acc. DIN 7080 25 25 acc. DIN 7080 30 40 disc special size 130 15 10 disc special size 135 15 8 disc special size 25 25 acc. DIN 7080 140 15 8 disc special size 150 10 2 disc special size 15 8 disc special size 20 10 acc. DIN 7080 25 16 acc. DIN 7080 30 25 acc. DIN 7080 160 20 12 disc special size 170 15 5 disc special size 20 10 disc special size 175 20 10 acc. DIN 7080 25 16 acc. DIN 7080 30 25 acc. DIN 7080 200 20 8 acc. DIN 7080 25 10 acc. DIN 7080 30 16 acc. DIN 7080 210 25 10 disc special size 250 20 4 disc special size 25 8 acc. DIN 7080 30 10 acc. DIN 7080 265 30 8 acc. DIN 7080   Note: if in the column Notes otherwise stated, borosilicate glass "extra hard" is used Round sight glasses are delivered separately or in a set with gaskets and mica shield. If you can not find the size - please contact us. Tolerances Diameter (d1):d1 ≤ 125 mm125 mm < d1 ≤ 200 mm d1 > 200 mm  ± 0,5 mm± 0,8 mm± 1,0 mm     Thicknes (s):s ≤ 20 mm s > 20 mm  + 0,5 mm / -0,25 mm+ 0,8 mm / -0,40 mm  Flatness (e):d1 ≤ 100 mm100 mm < d1 ≤ 150 mm 150 mm < d1 ≤ 200 mmd1 > 200 mm 0,05 mm0,08 mm0,12 mm0,15 mm    Parallelity (p):d1 ≤ 100 mm100 mm < d1 ≤ 200 mm d1 > 200 mm 0,20 mm0,25 mm0,30 mm Calculation of the glass thickness s - theoretical minimum glass thicknes [mm] dm => (d1+d2)/2 => average sealing diameter [mm]d1 - glass and sealing outside diameter [mm]d2 - sealing inside diameter [mm]p - permisible presure [bar] δbB - min. value of surface comressive stress [N/mm2] S - safety factor        Our offer includes sight glasses made of various materials, depending on environmental conditions (temperature, pressure, aggressive media). The properties of various glass materials are described on page Types of materials in chapter Our offer/Technical glass. The basic types of materials used for the manufacture of sight glasses are: soda-lime glass - widely available, cheap, working temperature up to 280 °C,  borosilicate glass - particularly suitable for use in aggressive environments (acids, alkalis, water vapor), working temperature up to 350 °C, aluminosilicate glass -  working temperature up to 660 °C, glass-ceramics - thermal shock resistant, working temperature up to 750 °C, quartz glass - with a broad spectrum light transmittance (from ultraviolet to infrared), working temperature up to 1100 °C, sapphire products - working temperature up to 2000 °C. To improve the strength, the machined glass is subjected to toughening and annealing. In order to increase the resistance of sight glasses on the aggressiveness of the working environment and in the use of high temperatures and pressures, additional use of mica shield is recommended. Mica disc working as shields are described here.  If you need this solution - please contact us. Round sight glasses are delivered separately or in a set with gaskets. Gaskets for sight glasses are described here. We offer sight glasses manufactured by leading brands such as: Spectraglass, Klinger or Maxos, which guarantees high quality and stability of parameters.   Safety precautions when using sight glass discs: Whenever a sight glass assembly has been taken apart it is urgently recommended in accordance with DIN 7080/ DIN 8902 that the glass disc and gaskets are replaced by new ones. That is particularly important in the case of pressure vessels and/or aggressive media. The following extract from DIN 7080/DIN 8902 text is verbatim: Sight glass discs may only be installed by personnel who have been informed fully about the following requirements: care in handling sight glass discs cleaning of recesses, sight glass discs, gaskets and other parts i. e. removal of foreign bodies (e. g. swarf), prior to installation/reassembly even tightening of retaining bolts Sight glass discs that have been removed after operating use must not be re used. Planned maintenance:Sight glass discs should be included in routine maintenance and periodically checked visually or using ultrasound wall thickness measuring means. In the event of damage, a glass disc must be promptly exchanged, with the plant first having been brought to a standstill. The service life of a sight glass, relative to the particular vessel in which it is mounted, should be established by regular and careful visual check of its condition.Caution: Completely demineralised water may dissolve glass – especially intensive periodical inspection required! Breakage of a sight glass:In spite of careful installation and recommended use, sight glass discs can, on rare occasions, suffer breakage through external influences. In order to prevent the entry of glass particles into products of a critical nature, e. g. foodstuffs, appropriate safety precautions should be taken by the plant manufacturer or user.  

Material: Base flange: RSt 37-2, H II, 1.4541, 1.4571 (factory standard) Cover flange: RSt 37-2, H II, 1.4541, 1.4571 (factory standard) Steel on request Sight glass: borosilicate glass to DIN 7080 Soda-lime glass according to DIN 8902 Seal:  Klingersil or as desired Screws:  5.6 galvanized, A2-70, A4-70 Shape: similar to DIN28120 but PN2.5 Nominal size: DN50 - DN200 Nominal pressure: up to 2.5 bar Temperature: With soda-lime glass up to max. 150°C With borosilicate glass up to max. 280°C With borosilicate glass & mica shield up to max. 320°C for higher temperatures please ask us. Miscellaneous: Special designs/options a) with wiper SWIb) with LED or halogen lights, also ATEX-certifiedc) with O-ring seal (suitable for vacuum)d) high-temperature version with quartz glasse) other special designs on request   SHORT DESCRIPTION - ROUND TANK SIGHT GLASSES TYPE 318 PN2,5 Our tank sight glass fittings Type 318 (PN2.5) are intended for welding installation into or onto a pressure vessel wall and provide a way to observe and illuminate the interior of the vessel. ACI tank sight glass fittings of Type 318 have been designed based on DIN 28120 for an operating pressure of up to 2.5 bar. Two flanges of high quality stainless steel 1.4571 (316Ti) surround a glass disc made up chemically highly resistant borosilicate glass 3.3 according to DIN 7080, creating a nearly maintenance-free inspection port. Contrary to the sight glass fittings described in DIN 28120, our Type 318 is significantly thinner and the hexagon head screws barely protrude out of the cover flange, thus reducing the space required for installation. Type 318 closes the gap between our non pressure retaining Type 317 and the stronger types 319 and 320. The sight glass fitting is sealed using flat gaskets specifically selected for your application from our vast range of gasket materials. Apart from commonly used aramid fibre gaskets, we can offer Type 318 with sophisticated materials like PTFE, NBR, graphite composites and many other gasket types. If the glass disc’s maximum operating temperature of 280°C does not suffice for your application, or your process fluids are challenging even for highly resilient borosilicate glass, a mica disc specifically fitting your sight glass provides additional protection of the glass surface against steam or aggressive chemicals like highly alkaline solutions. Like the rest of our tank sight glass fittings, Type 318 is available equipped with wipers type SW1, spray nozzles or light fixtures. Read on to learn more technical details of our Type 318!