No basket filters are used. So much junk can be potentially caught in a pig trap that the filter would become clogged immediately and you might have to clean it 100 times or more for each pig run.
If you did want to try to use one, where would you put it? Upstream of the trap, the pig would hit it. Downstream of the trap it would not catch anything, because the pig just pushed the junk out into the trap.
"Is anybody aware of basket filters installed on a pig trap?" Never ever seen or heard of for all the reasons BI states
I've seen pig traps rammed full of sand and debris but never filters. In gas systems when you first pig them you can clog up the downstream filters pretty fast with dust....
"If yes, exactly in which position?" See above
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
I actually did see a basket strainer in the pipe coming off the receiver bypass in an oil line one time. The bypass was a 6-inch line with the basket inserted into the flange on the side of the receiver (to clean it you broke down two 6-inch flanges and dropped a heavy 12 ft section of 6-inch pipe). The one time it was used it completely stopped flow about 20 minutes into the pig run and the line had to be stopped to clean it. Needless to say the basket was not reinstalled after the first time it was cleaned. I never talked to the designer to determine what the heck he was thinking, but the field guys had some truly epic (and very ugly) things to say about the engineer that thought this would be a good idea. I suppose you could put a duplex strainer on the bypass and have a functional system, but I don't see the upside.
I often put line drips downstream of receivers as a preliminary slug catcher (in gas lines) and the fluid that comes out of them is often quite nasty. I sure wouldn't ever put anything more restrictive than that.
