PN16 Flange leaking

[petthebuilder]

Hi,
I have an issue with a supplier and I try to put my mind at ease.
The situation is the following. PN16 flange - 4" to 4"-2" malleable reducing bush is leaking. I use Loctite 55 with a smear off La-CO Slictite to make the installation smooth. the number of threads of the Loctite 55 followed to the T.
Any how it was leaking at 1 bar pressure, so i dismantled the application and remade the joint (took 2 hours). and it leaked again. So I went down to supplier and picked up a new one. Assembled the same way as usual - no leak. So I took the one existing one back to them. I made a mistake of not disassembling the connection (flange and reducer together) and they were claiming that the thread is not run fully together. although it has not leaked ever on any of my connections before. now I am in doubt. the flange and the reducer has at least 10mm connected thread lenght. which means the 4" male thread of the bush is in half way to the pn16 flange female thread. I will also upload some pics.
Could anyone advise me on the minimum thread numbers for connecting 4" iron pipes for low pressure applications (3bar)?
Thank you in advance.
Peter

 

[petthebuilder]

Please see image of the flange and reducer.

 

[petthebuilder]

Sorry , I am new to this.
Please see image of the flange.

Untitled

• petthebuilder
• 6 Jul 2014
• 1

Untitled

• petthebuilder
• 6 Jul 2014
• 1

 

[Richardthe3rd]

The bush going into the PN16 is well shy at only 10mm thread. What size Stilies are you using?? I'd use at least a set of 36" to bury that bad boy.

 

[petthebuilder]

Hi. Thank you for your reply. It may be more than 10mm. It's a good half of the internal thread of the flange. Peter

 

[Richardthe3rd]

If it's watertight I'd not worry Peter. Tell your supplier that the fitting is 'below merchantable quality' & you want your money back. The chances are they'll clean the flange & bush up then stick it back on the shelf.