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The 8×22mm Nambu is a semi-rimmed, bottleneck handgun cartridge introduced in Imperial Japan in 1904, used in the Type 100 submachine gun and Nambu pistol. The 8×22mm round was used during the Pacific War and Second Sino-Japanese War.

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  1. V

    Central Heating - Blocked 22mm return pipe?

    Hello all. I've just joined, was going to post in the new members forum, but the first site generated email sent me here... I am here, as have a challenging and interesting problem, which I'll try as best to describe below keeping to the point and as short as possible, to avoid boring any of...
  2. J

    Why hot water copper pipe is 22mm and cold is 15mm?

    Hi All, I have this silly question. Water pressure for hot water is a bit low while cold water has a decent pressure. Why do they put 22mm copper pipes for hot water? It seems detrimental for already low pressure. Best regards
  3. M

    URGENT 22mm copper pipe of 28mm copper pipe, what shall I run?

    Hi all. I'm new to this forum. Please go easy on me👷🏼 I'm currently renovating my house and my house currently runs from old lead pipes then soldered in to 15mm copper pipe. I want to replace the whole piping in the house from to bottom. My question is shall I run 22mm copper pipe then...
  4. E

    Is there a max run of 15mm from 22mm allowed?

    I am replacing a large (~2m long) old radiator below a window with a vertical one beside the window. The current rad tees off the old pipe (22mm diameter) and runs directly to the rad. Can I just cut into that tee'd section and extend to the new rad location that is about 2m away? Would this...
  5. B

    How many radiators off a 22mm flow

    Hi all I currently have 6 old radiators (downstairs) off what looks like 15mm pipework. It comes off the zone valve in 22mm and then goes under the suspended floor and is 15mm throughout. It takes forever to heat the rooms and as the radiators need replacing anyway I was looking to upgrade to...
  6. I

    Pressure gauge for 22mm pipe

    Hello, Can someone be kind to tell me what parts do I require (and where from) if I want to fit a pressure gauge on a 22mm feed, I guess I would need a tee to house the gauge, cant seem to find anything online. Many thanks
  7. J

    Gas pipe oversizing. 22mm vs 32mm

    Just to be really clear I will not be doing any of the work mentioned below. This will all be carried out by Gas Safe Engineers. I'm looking to get a Gas Safe engineer to move a boiler from the main house to the garage. As part of this process I will also be getting the main gas supply and...
  8. Ccw1971

    Advice - 15mm gate valve to 22mm flow

    Hi, new member here, so hello! I recently bought a house that needs heaps of work, so have no money and lots to learn along the way. Ive had a new WB 8000 Life 40kw system boiler installed on my gravity fed system. The house is a long bungalow with roof rooms which had no heating so I asked my...
  9. P

    Is 22mm pipe worth it when using a 15mm pressure equalising valve?

    Hi all Making some final decisions on the plumbing for our bathroom refit. Background: we'll be having a shower mixer tap on the bath, hot water is gravity fed, and cold is mains. So I'll be having a pressure equalising valve (PEV) before the shower mixer to balance the hot and cold. I know...
  10. D

    22mm speedfit to waste pipe???

    I'm installing a waste pump in wet zone area(ground floor concrete) Waste pump has 22mm feeds which I would normally connect to soil pipe with boss strap. However the soil pipe is clay embedded in concrete with a 90° pan connector going straight into the ground. I've seen the pan conns with...
  11. M

    Capping 22mm hot water pipe

    Hello, as per title I need to cap off the hot/cold feeds to the bath before I rip it out. Its 22mm copper feeding into flexible pipe to the tap. I've just checked and my pipe cutter only does 15mm. Given the picture below, is there a capping with a male end I could screw replace the Flexi...
  12. W

    URGENT 22mm to 28mm boiler

    hi all Iam installing a new combi oil boiler the old boiler (system boiler) had 28mm feed and flow connections new combi has 22mm Iam ok to connect the 22mm straight into the 28mm pipes
  13. B

    Will a 22mm pipe cutter work on older 3/4"?

    Hi All Pretty explanatory really, need to cut some old 3/4" pipe feeding H+C bath taps, access is very tight. Will my 22mm cutter work on 3/4", if not what can i use? Thanks
  14. G

    Reducing 22mm pipe to 15mm

    Hi, We've recently had a pressurised hot water cylinder installed. When we use the kitchen tap it's quite a long run so the hot water takes a long time to run hot. I could fairly easily reduce about 7 metres of 22mm pipe down to 15mm (it already reduces to 15mm upstairs anyway before dropping...
  15. B

    Danfoss Randall HS3 22mm Motorised Three Port Mid-Position Valve

    recurring Issue, any help would be greatly appreciated. I have changed this valve twice in the last 3 years........ is this normal or would i expect to get longer use out of this valve?
  16. B

    Need a concealed thermo valve with 22mm inlets and 150mm centres

    Hi, I'm looking for a concealed thermostatic valve with 22mm inlets and 150mm centres. Something with a brass construction but not £300 or over. I'd be very grateful for any help! thanks, Ben
  17. ShaunCorbs

    Honeywell 2 port valves 22mm

    Anyone got any looking for 6 possible more
  18. A

    38kw combi boiler supplying a shower. 22mm or 15mm pipework?

    38kw combi boiler supplying a shower. 22mm or 15mm pipework? I am refurbishing a 1st floor bathroom and installing a shower to replace a bath and have a 22mm/15mm pipe quandary. There is currently a newish Worcester Greenstar 38CDi Classic combination boiler and my question is should I redo...
  19. Meady

    Honeywell 22mm V4043 2 port zone valve for sale

    I have 11 of the above for sale, all are brand new and in the original box. Looking for £40 each posted for them. Cheers 1596736173 10 already sold, just the 1 left now. Cheers
  20. S

    Max distance for 10mm tails off 22mm flow and return

    I’m considering my options for moving (JG) pipework from an inaccessible place whilst the floor is up. One option might be to use 2 x JG 4-port manifolds, mounted in a much more convenient location. But, this would mean adding 2 - 3 metres to the 10mm tails (off flow and return) and i’m not sure...
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