How do I.. remove this drain cover!?

[Mr Gus]

Thanks all for the replies & offers, of assistance.

My reasoning for wanting to grease it at point of replacement is that the hoise was built in the 1970''s (linoleum tiles straight to concrete) the then outdoor drain access had a conservatory built over it & was tiled,, lifting the cover has gone from a simple lift & drag circa 2002, to awkward in 2009 (cracking a tile) & downright nasty this year ..necessitating a 2 tonne jack assist, even then it wasn't straight forward, we partially lifted in order to presumably let any galv / iron corrosion slowly decouple as resistance seemed to imply that, ..thus If I were not to performsome kind of greasing this time I think we'd be in schhtook next time round,

Having fou d out that it was a protruberence of hardened limescale beyond rod reach, I'm wondering what would be a "maintainence" action periodically?

(the guys who attended stated they often get acid burn as folk have generally tried everything before they call them out, ..we tried various bio friendly treatments in case it was an "eat away" solution, before eventually moving over to alu-pins & caustic soda treatment "bombing" to no effect (limescale build up too far down) removing the slurry & bunging 5 litres of bleach in the remaining "water" to ensure the open sewer was as dead as possible (we did cover it with something else to monitor flow ..lack thereof.

Im guessing a periodic sacrifice of vinegar? (it's not like it can sit & soak though)

[Fintray]

I know it doesn't help now but when the conservatory was being built the drain cover should have been swapped out to an hermetically sealed one which is suitable for indoor use and has a neoprene seal fitted. I had this option when I had an extension added but it was simpler to move the access chamber to outside the extension footprint.

[Mr Gus]

Yeah, it was another "shonky, dodgy vicar" DIY episode, same as nigh on bellwire in the utility room ..for a tumbledrier & washing machine.I
(nearly a fire)

[Mr Gus]

Thanks for your help guys, chandlery recommended a Morris lubricants calcite K99 grease @£7 a hit (general purpose, so car doors et al) matching up with your advice perfectly. ..boat yard not far from me (though may pop into my local garage & check there)

Way different to clarks drain grease gramme for gramme on price eh!?

https://www.morrislubricants.co.uk/prod ... d35821.pdf