Robco Expert

What gasket material to use on sheet metal flanges for ventilation systems Jocelyn Vachon - VP B.Dev / Product Specialist Gasket materials require to be compressed, in order to achieve a seal. What materials should you use when flanges are simply made of thin sheet metal? Ventilation systems assembled on-site require gaskets between sections. Sheet metal flanges cannot create a high, evenly dispersed mechanical load on gasket materials, even if internal pressures are low (6 to 12 inch of water on average).   Here are a few suggestions: Closed cell sponges with a durometer of 20 to 60 (shore 00 scale) are good options Neoprene-based sponges (Robco SC-41 soft / SC-42 medium / SC-43 firm) are the most popular. Self-adhesive strips can be formed (round flanges) or cut in lengths (square flanges) for a quick and wasteless assembly PTFE saturated woven glass tapes (Robco GW-305) can be used where temperatures are above 250°F (130°C) and where a ...

   ASME PCC1-2019 : notes techniques sur les performances d'étanchéité Lotfi Grine, Eng. – Spécialiste de produit chez Robco   Dans les notes techniques suivantes, vous trouverez de précieux extraits techniques de l'ASME PCC1 2019 (directives d'assemblage de brides boulonnées (BFJA)) pour aider à mieux comprendre le comportement d'étanchéité et produire une étanchéité positive.   - Le calcul des valeurs de couple cible est basé sur la zone racine. Les zones de racine sont basées sur une série de gros filetages pour les tailles de 1 po et moins avec une série de pas de filetages de 8 pour les tailles de 1 1/8 po et plus (section H).   - La principale valeur à long terme des boulons revêtus est de protéger contre la corrosion des filetages exposés et de minimiser le couple de rupture et de retrait d'écrou, facilitant ainsi le démontage des joints (Section 7).   - La section VIII, division 1 du code ASME sur les chaudières et les appareils à pression e...

  ASME PCC1-2019 : technical notes about sealing performance Lotfi Grine, Eng. – Product Specialist at Robco   In the following technical notes, you will find valuable technical extracts from the ASME PCC1 2019 ( bolted flange joint assembly (BFJA) guidelines) to help better understand sealing behaviour and produce a positive seal. - Calculating Target Torque Values are based on the root area. The root areas are based on coarse-thread series for sizes 1 in. and smaller with 8-pitch thread series for sizes 1 1/8  in. and larger (Section H). - The major long-term value of coated bolts is to protect against corrosion of the exposed threads and to minimize break-out and nut-removal torque, thereby promoting ease of joint disassembly (Section 7). - Section VIII, Division 1 of the ASME Boiler and Pressure Vessel Code requires that nuts engage the threads for the full depth of the nut (Section 8.2).   - Start-up re-torque is performed when the temperature of ...

Choosing the right type of stainless-steel grade to use for spiral wound gaskets is important. Lotfi Grine, Eng. – Product Specialist at Robco The media concentration, temperature and time requirements provide a variety of work conditions for spiral wound gaskets.   The metal components are subject to different types of attack, including pitting, cracking, stress corrosion cracking and intergranular corrosion. It’s important to specify, that the standard stainless-steel used for Robco SWG is normally Type 316L . Other high quality alloys are available (ex : hastelloy, inconel, monel, etc.) for higher temperature or other special applications Here are the particularities of stainless-steel grades used generally in the manufacturing of spiral wound gaskets: Stainless steel type 304 serves a wide range of applications. It resists organic / inorganic chemicals. The main limitation of Type 304 is stress corrosion cracking and intergranular corrosion when the temperature exceeds 800°...

  DO NOT MACHINE COLD OR HOT THERMOPLASTICS by: RedOps / Robco When receiving thermoplastic sheets, rods, tubes, etc... Do not begin machining them until they have been allowed to sit at room temperature 24 hours. This will allow the thermoplastic to regain its nominal dimensions. This is inherent in thermoplastics, since they expand and contract with temperature.

  HOW TO WRAP PIPE WITH HIGH TEMPERATURE TAPE by: RedOps / Robco Rule of thumb is wrapping the tape for the first turn around, then start the second wrapping halfway over the first and continue this pattern for the entire tape wrapping of the pipe length.   This will create a double wrapping of the pipe and this is the best practice for protection. Just as you would do on a hockey stick!

OVER GREASING KILLS BEARINGS  by: Red Ops / Robco ·      Overfilling bearings with grease is the most common cause of bearing failures. ·      Too much grease in the cavity/bearing will cause more friction to run the bearing and that will result in an increased temperature to levels above the drop point of the grease: oxidation will occur and both the grease and bearing will prematurely fail! ·      Follow the instructions of the bearing manufacturer for greasing quantities as per bearing type and size. ·      Take into consideration the environment, temperature and operating hours.   OVER GREASED BEARINGS PROPERLY GREASED BEARINGS