Monday, 26 August 2013

Anson Engine Museum

Today dawned clear and sunny, so we'd arranged for the little bikes to go to Higher Poynton to visit the Anson Engine Museum, who were hosting one of their three days a year when their big cross-compound steam engine is in steam. Why only three days a year? Because it costs them £500 in gas to generate the steam in their boiler to power the engine.

We began the day with breakfast at the Bollin Fee, which is becoming a bit of a habit. But it sets one up for the day and negates the need for lunch.

Malc enjoys Eggs Benedict, while Ivan and me go with the traditional breakfast

We arrive at Anson; Malc with his Townmate, my C90, and Ivan with the SS50 

 The first machine we watched in action was of a type not too well known. It has a vertical cylinder where the piston is fired up the cylinder, rather like a vertical cannon. Attached to the piston isn't a connecting rod, and there is no crank to convert the vertical piston movement to useful rotary power. Instead, attached to the piston is a rack that drives a pinion. But the power stroke, where the piston is forced up the cylinder by igniting gas, isn't the one that drives the pinion. It's the descending stroke where the rack drives the pinion to produce rotary power. And the piston is made to descend by the partial vacuum left in the cylinder after the power stroke. Click on the link to see it running (sorry the video is 90 degrees out; one day I'll discover how to correct that!)..

At the base of the engine is a clever bit of kit that admits the gas to the cylinder, transfers a pocket of lit gas from the pilot gas light into the cylinder to fire the charge, then opens the exhaust port to allow the burnt gasses out.

This engine used to run on town gas, but today propane has to be used, with hydrogen for the pilot and transfer flames.  

The amazing Deltic engine:

A sectioned Napier Deltic 2-stroke opposed piston engine

The Deltic comprises three banks of cylinders with opposed pistons in a 'delta' plan form with three geared-together crankshafts, one at each corner of the delta. On the left in the picture can be seen the centrifugal impeller of the supercharger. 

The Deltic was conceived as a marine engine, but found fame when English Electric used two in each of their Deltic diesel electric express passenger locomotives used on British Railway's Eastern Region on Kings Cross to Edinburgh services, replacing Gresley's iconic A4 pacific steam locomotives.

There were several small engines running, including this one. It has a 'hit and miss' intake valve controlled by a speed-sensing governor. Only when the revs drop does the inlet valve open and a power stroke is produced. Click on the link to see one in action.

A couple of the museum volunteers were trying to get this engine going. Click on the link to see Ivan watching them cajole it into life:


The Deltic is a pretty unusual configuration for an internal combustion engine, but how about this? It's a Bentley W12 car engine, with two sets of V6 cylinders mounted above a common crankshaft.

Meanwhile, down at the forge the blacksmith was using his hammer. It's driven (in this case) by a diesel engine, but obviously steam could be used. The small constantly-driven piston charges a reservoir of compressed air which is used to drive the big hammer. Click on the link to see it in action (sorry, it's another one 90 degrees out).

But what attracted us to come today was the big 250hp cross-compound steam engine in operation. It didn't start first time because the high pressure cylinder's inlet valve was closed. Once that was corrected, away it went. Being a compound it has a high and a low pressure cylinder, in a cross compound these are arranged one each side of the crank shaft. The engine also has a condenser which would provide vacuum assistance on the exhaust stroke of the low pressure cylinder, but that would require a large water supply (to condense the exhaust steam) that Anson doesn't have, so the condenser and its associated air/condensate pump is not used. The engine is relatively simple; it has Corliss valve gear for the high pressure intake valves, but the exhaust, and all low pressure valves are simple rotary valves. There is no facility for varying the valve gear setting and therefore the steam cutoff - it's fixed. Click here to watch the engine start and run:


After such a strenuous afternoon at Anson, it was time for a drink. We headed down the lanes from Higher Poynton to Bollington, admiring the superb views to our right over the Cheshire Plain, to the Vale Inn. The Vale has its own brewery, and here Malc and me enjoy the lovely hoppy Bollington 'Long Hop', while Ivan has their traditional 'Best Bitter'.

Me and Malc enjoy our pints in the garden of the Vale Inn

From Bollington we found 'Long Lane' up a steep hill out of the village on the valley side, again with superb views over Cheshire once 'up at altitude'. From there we passed Adlington Hall and were soon home.

Another great day out!


No comments:

Post a Comment