South Crofty Mine Inside 1: This page contains internal images of both the Winders also the Compressor House. It was rare for those I knew at the mine to have time to show me around.
So, on this occasion I made the most of it. These buildings housed the life of the mine, the winders were the heart. Also the compressors supplied the air which gave life to the drills and machines used deep underground.
All of these images were taken when the mine was still open.
South Crofty Mine Inside 1.1 – The North Winder house of South Crofty. This winder, was one of two employed on site, this image shows the twin drums and breaking arms. These drums had a diameter of 3.81m, they weigh 26 Tons each and would rotate at 38.3 R.P.M.South Crofty Mine Inside 1.2 – Another image of the North Winder constructed by Markham who still operate as a supplier of mining machinery. This was used for bringing the skips of ore up the shaft. It worked on a 16 hour a day basis. Getting the ore out was a very costly operation which substantially added to the operating costs of the mine.South Crofty Mine Inside 1.3 – The 35mm wire rope on one of the drums, this had a Breaking Load of 105 Tons. In the foreground are the drum breaking arms.South Crofty Mine Inside 1.4 – The power unit of the Winder, this had a motor speed of 710 R.P.M.South Crofty Mine Inside 1.5 – The skips could carry between 6-8 ton, the winder would bring them to grass at 25ft per second.
Colin Coombes was an Underground Electrician at South Crofty Mine. He carried out electrical maintenance on both winders during the years 1988-1990. He has written a short account for this page.
Maintenance was usually carried out on the winders on Saturdays. Firstly we had to check the signalling system down the shafts on each working level up to surface. To verify correct operation. The 3.3kV supply was then isolated to the winder and locked off with special safety locks so it was safe to start work.
Contacts where required were cleaned on the switchgear. Also oil and electrolyte levels checked and topped up if required and connections checked for tightness.
On completion of the maintenance, supply was restored. Then run through operation of all safety circuits, overspeed for man riding and ore carrying. Other safety trips tested, once all were confirmed to be within required limits so the winder was restored to normal operation.
South Crofty Mine Inside 1.6 – The first image of South Winder in its house. On the right is the driver’s cabin, on the left the giant electric motor.South Crofty Mine Inside 1.7 – The South Winder was used primarily for manriding it was built during 1959 by a company called Fullarton. It was installed here during the 1970’s . Purchased from a closed colliery, it was also converted from steam to electric power.South Crofty Mine Inside 1.8 – The massive drums were 16ft in diameter. There was enough 1 1/2” steel rope to drop the 2,400ft shaft, however a maximum reach of 3300ft was available. In the foreground is the 1550 HP DC power unit.South Crofty Mine Inside 1.9 – A closer view of the winder, this shows the massive breaking posts. The horizontal tensioned arm above the drum was attached to the breaking engine.
The winder was equipped with a Ward Leonard control system. This was a very smooth speed control system over a very wide range (from zero to normal speed of the motor). The speed could be controlled in both the direction of rotation of the motor easily, so the motor could run with a uniform acceleration.
South Crofty Mine Inside 1.10 – The 1 1/2” steel rope coiled on the drums, each drum are 3’9″ wide. On the rim are specific marks and an indicator arrow for the drivers reference.South Crofty Mine Inside 1.11 – The front of the drums, the apparatus in front is part of the Lilly controller.
This was a wonderful device. The driver will say that he drives the winder, but in reality the Lilly controls/monitors what the winder driver is doing. If events move outside the parameters set by the Lilly, it will firstly alarm, then shut down the winder in a safe mode.
(Information kindly supplied by Bob Orchard)
South Crofty Mine Inside 1.12 – One of the twin drums. The tensioned breaking arm can be clearly seen with the breaking blocks sitting on the rim.South Crofty Mine Inside 1.13 – The drum and breaking arms from the other side.Cornish Mine Images 1.14 – These drums would rotate at around 28 R.P.M, the rope can be seen going through the slot in the wall of the house. The cage was lowered down the shaft at a speed of 21ft per second. Cornish Mine Images 1.15 – There were many safety features built into the winder. The brakes would automatically be applied if, the power failed, in the event of an over wind, if the drivers trip switch was engaged, if the winder went too fast. Also if the driver attempted to start in the wrong direction, failure of oil supply or any component failure. Certainly a wonderful piece of engineering.
The remaining images were taken in the mines Compressor House.
This machine is a Ingersol Rand “Centac” is a centrifugal compressor producing 5,500 cubic feet per minute capacity. It was also supported by three smaller machines. The air was fed down the shaft in pipes to be distributed to the working miners underground.
Cornish Mine Images 1.16 – All the machinery used for mining was driven by compressed air. This is a picture of the main air compressor at Cooks shaft.Cornish Mine Images 1.17 – A more detailed image of the power unit.
