The forging press cylinders always work in high speed and large shock condition，which is a big challenge for seals and mechanical structure.Thanks to the cooper alloy guide ring，the cylinder can move smoothly and have a longer service life under large lateral load. The Reasonable structure design reduce the stress substantially, achieving a high reliability. The largest press cylinder made by Hengli has a amazing bore diameter-1800mm,which is based on Hengli's extremely strong manufacturing and testing capability.