Re: Welded Joints Or Flanged Joints
1) Either type of pipe joint is acceptable for conveying. From a practical point of view though I remember one project where the contractor decided to save money on flanges by making a 1 km long conveying pipe fully welded. They blocked the line once on commissioning and then spent many unhappy days cutting pipe and installing flanges to allow them to clear the blockage.
2) I thought lime was a fairly soft material and didn't give significant wear on pipelines? If it does, there are options including basalt / alumina lined bends wear resistant runner (at the expense of a higher pressure drop, etc. Options like this tend to be expensive and the severity of your wear problem will determine what is the optimum level of spend to give you a reasonable life. ■
Re: Welded Joints Or Flanged Joints
Lime is not abrasive at all but is very prune to pipe build up especially at the pick up point depending on its type and conveying conditions.
As far as flanges are concerned RPD has made the point very well. If you don’t want flanges there are other options such as compression couplings. ■
Re: Welded Joints Or Flanged Joints
As has been previously mentioned some allowance for clearing blockages is required.
I wonder if the flanged joints, though, contribute to the blockages (material maybe caught on the "rough" surface). I suspect in an appropriatly designed system this is not such an issue.
Regards,
Lyle ■
Re: Welded Joints Or Flanged Joints
While in general, lime is not normally expected to be abrasive, b ut you are obviously experiencing wear and erosion or otherwise you wouldn't be askling how to solve the problem so i assume you may be talking about some forms of limestone or have other materials in with the lime.
There are numerous designs of elbows with integral and replaceable wear backs which can be constructed of special wear resistant materials. Abrasion resistant coatings and ceramic liners have been added to the interior surfaces of elbows to increase their like.
There are companies who make elbows in special geometries which are supposed to form a "pocket" of material which absornbs the energy of the incoming product in order to keep it away from the pipe wall.
All of the above options have been proven successful in some installations and have failed in others. The common factor is that they all tend to address the problem and not really try to solve the original problem.
Conveying velocity is the key factor which influences wear in a transport system. The lower the conveying velocity the lower the wear. That statement is not always as simple to acheive as it may sound, but it is the fundamental parameter to look at first.
ou ■
Welded joints or Flanged joints
Dear Sir,
I am interested to know that, 1) What type of pipe joints is good for pneumatic conveying of (-)3 mm lime fines? welded pipe joints or flanged joints at the bends of pneumatic transporting pipes?
2) How can we improve the life of pipe at the bends from erosion, in pneumatic conveying of lime fines?
Regards,
S.T.Selvam
India. ■