Longer Life for PF Mill Cylinders
FTL Technology are now manufacturing a new nitrogen actuated cylinder for the Power Generation and Cement industries. RodasRam is a designed, developed and patented cylinder to replace the existing hydraulic/pneumatic cylinders currently in use on the Babcock 'E' type mills. These mills were designed for the pulverisation of coal at power stations and cement works worldwide.
The advantages and benefits of the new 'Rolling Diaphragm' cylinder are numerous:
- Oil free system - nitrogen only
- Nominal life 30,000 hours (actual 50,000 hours completed on site)
- Individual isolating valve for each cylinder, plus minimess test point to enable testing whilst in operation
- Low maintenance cost and reduced downtime
- Low repair costs
- Environmental improvement
- Operates at 50% lower than current working pressure
Some of FTL's actual installations are...
Ferrybridge was our first installation in the UK and had the first set of 8 cylinders installed in January 2003. The plant has since fully converted a further 9 mills.
"The rams are proving very reliable. The service provided by both Andrew Hewitt and Mark McCormack has been excellent, and they have shown themselves to be highly competent by resolving technical issues quickly and efficiently."
FTL Technology has installed a set of rams plus control panel and pipework at the Lafarge Hope cement plant. On the 10E mills, the ram position is at the bottom of the cylinder and by way of a flange connects to the push rod.
The cylinders on the 7E mills are hung from the opposite end to the more standard 10E type mill. There are fulcrum arms connected to the cylinder clevis which transfer load up to the top ring.
"The new design control system is far less complex, yet gives us the ability to run full diagnostic checks on each individual cylinder. If a cylinder is found to be malfunctioning, the system is designed to allow us to isolate it and replace it on the run. Cross contamination due to pressure leakage is no longer an issue, plus the elimination of oil leakage helps environmentally, which we see as a major benefit."
The cylinders are also in use at Ratcliffe-on-Soar Power Station. The only difference between Ratcliffe and Ferrybridge applications is the hanging arrangement of the cylinders.
"We are delighted with the cylinders and see the installation as a big winner. There was a lot more potential for leakages with the old system and the control cabinet was overcomplicated; maintenance costs will drop, and no oil leaks makes everything look cleaner, while removing a possible fire risk."