Member postings for David Jupp

When dealing with very large items which can be very slow to cool, there are circumstances where detrimental changes can take place due to diffusion whilst air cooling. Certain 'tramp elements' can migrate towards grain boundaries, leading to a reduction in toughness of the final product. In such cases quenching after tempering is important to maximise toughness. Such industrial practices may be at the root of some of what is written about heat treatment.

I doubt that many of us need to worry about such things.

Robin

Left hand side of data plate is the main motor, right hand side is the cooling fan.

It's common on variable speed drives to have a separate fixed speed motor for the fan.

Camden has it on their web site, but showing 'currently sold out'.

I found this article which covers many aspects of getting reliable one-wire communication - not sure how many of the points covered are relevant to the OP's application.

Andrew, Gas Oil is pump diesel but with much reduced excise duty, so should still give a big saving. A generator would seem to be a legitimate use for Gas Oil.

When I worked on a major Petrochem site, all the diesel engines vehicles used only on site (not on public roads) ran on Gas Oil.

Your oil supplier may be able to give some assistance - this web page has quite a bit of information for example

https://www.crownoil.co.uk/guides/fuel-specifications-guide/

Looks like pump DERV may not be as helpful as the grade D Gas Oil in terms of lubricating properties for older equipment...

Could be an ISP / DNS issue perhaps...

The link to Mintronics site works OK for me. Which browser are you running Ady?

Contact details are also available from the 'Buy' button on the main alibre.com site - from outside North America, it will open a list of international re-sellers - UK is near the end of the list.

Alibre does do radians - but it will display in your chosen preferred angular unit.

Alibre works internally with radians, like many computer systems do - so an arc length is simply given by

arc length = radius * angle

Alibre's equation editor is VERY FUSSY about variable typing, which can lead to some unexpected problems if you are not aware of them.

This page may be helpful - it's on an old system, so could vanish (I can provide it as a PDF if needed).

4 stoke pistons will typically have an oil control ring in addition to the compression rings.

Most (not all) 2 stroke pistons won't have the oil control ring.

It's ISO 702-2 that has dimensions / drawings for Cams and Studs.

In UK, your local library may have on-line access to British Standards to allow you to view this for free (though cuts have meant that some library services no longer subscribe).

Please can we keep this on topic? I'm aware of the risks of seized valves (I judge it unlikely - I could be wrong, risk is on my own head. This is NOT a stop cock - it's a service valve (1/4 turn ball valve)). I do know where the stop cock is, and that isn't seized.

All I'm looking for is if anyone knows a name/term that might help to find a similar valve or the matching key via a search engine (as everything I tried had failed).

I'll probably end up choosing a few different diameter rods from my scrap box, round one end in the lathe, cut a slot with hacksaw then go to site and file to adjust.

Dave / Old Mart,

The valve is inside a boxed in section of wall just inside the property. There is already a hole for a valve key in the board over the pipe/valve. As the valve is inside (and assuming it to be a 1/4 turn) valve, it is unlikely to have seized - if it has that will become obvious when I attempt (carefully) to turn it.

Replacing the valve would require removing/replacing the boarding, and consequent re-decorating - hence I'd like to try closing the valve through the access hole that was clearly put there for that purpose. It's a pity no key was provided!

Martin,

Thanks - I'm pretty sure it is a 1/4 turn ball valve, similar to the ones that have a screwdriver slot. I can just make out compression fitting at one side of the valve when peering down the hole in the wall.

I was hoping to find either a key, or details of the valve that I could measure/estimate sizes from to make my own key.

I've come across a water service valve buried in house wall. It's an isolation for exterior tap, and the only access (without pulling wall apart) is down a small hole perhaps 10mm diameter.

Rather than the standard screwdriver slot to twist the ball, this valve has a raised bar across a rounded dimple.

I speculate that the key/tool to operate it would look like

I've searched on-line for similar valves, or the tool to operate, but have failed to find anything. Does anyone here know a name for valves of this type? or where I can get a key?

I can make a key, but will be largely guesswork as measuring down the access hole is not easy.

Edited By David Jupp on 20/11/2022 17:04:10

If planning to make a new part anyway, consider drilling or turning the part away to release the washer.

The builder of our house fitted cheapest available of most items. I replaced the first central heating pump like for like after a few years when it failed (partly seized, would not start reliably). The replacement went very noisy after a few more years (turned out impellor was loose on the shaft).

Being fed up I asked at a nearby heating spares supplier if they could recommend a higher quality pump. They did, it was quite a bit more expensive than the 'basic' brand. I installed it - immediately noticed it was MUCH quieter in operation, and I've now forgotten how many years ago it was purchased. No trouble since.

Could be for a temperature sensitive switch, or a thermistor as Dave suggests. Either can be used to indicate when the windings get hot.

Checking the resistance should determine which it is, if zero ohms it's a switch.

Or use the feedback form on their site

https://www.silverlinetools.com/en-GB/Support

Edited By David Jupp on 14/10/2022 15:23:58

Search for 'wedge wire screen' or 'welded wedge wire' - there are several UK suppliers.