jchumley
Electrical
- Jul 10, 2003
- 11
As you can see, I'm not a mechanical engineer. I would appreciate it if your responses are in as few non-technical terms as possible.
I work for a firm that manufactures air-to-air heat exchangers (recuperators). These are basically welded plate or tubular type recuperators operating at various temps and always at low pressures (<2psig) since they are not ASME or TEMA rated vessels.
I typically run into issues where customers have Cholorides, or Sulfur in their air-stream and I have to select a material. I generally defer to the metal vendors.
My current application is as follows:
Cold inlet = 100F, Cold outlet = 400F
Hot inlet = 530F
Customer has Chlorides in the COLD airstream at one of two levels, either 30ppm, or 180ppm. The cold airstream is fairly dry with only about 5% H20 by volume.
I had originally quoted 304LSS construction before knowing about the chlorides. Generally I recommend 316LSS for small levels of Chlorides and a metal like AL6XN (254SMO) or something more exotic if the levels are high. However, these levels seem low and we won't be condensing.
The customer is asking if standard HR carbon steel would be acceptable and quite honestly I don't know. I'm hoping you guys have and are willing to share your opinions.
BTW: I would appreciate a good reference on a resource for this type of issue.
Thanks in advance for your help.
I work for a firm that manufactures air-to-air heat exchangers (recuperators). These are basically welded plate or tubular type recuperators operating at various temps and always at low pressures (<2psig) since they are not ASME or TEMA rated vessels.
I typically run into issues where customers have Cholorides, or Sulfur in their air-stream and I have to select a material. I generally defer to the metal vendors.
My current application is as follows:
Cold inlet = 100F, Cold outlet = 400F
Hot inlet = 530F
Customer has Chlorides in the COLD airstream at one of two levels, either 30ppm, or 180ppm. The cold airstream is fairly dry with only about 5% H20 by volume.
I had originally quoted 304LSS construction before knowing about the chlorides. Generally I recommend 316LSS for small levels of Chlorides and a metal like AL6XN (254SMO) or something more exotic if the levels are high. However, these levels seem low and we won't be condensing.
The customer is asking if standard HR carbon steel would be acceptable and quite honestly I don't know. I'm hoping you guys have and are willing to share your opinions.
BTW: I would appreciate a good reference on a resource for this type of issue.
Thanks in advance for your help.
