Key Technology Research To Cryogenic Can Pump In Ethylene Plant

Ethylene production is the signature for the national development of petrochemical industry, as well as the national economy. Nowadays, Chinese ethylene production take up the second rank in the world, with 7% annual increasing, which cannot meet the requirements for local production. Our new ethylene plant in size between 80 to 120 tons/year means that large-scale supporting equipment is necessary, especially in key devices. Cryogenic barrel casing pumps used for the transportation of flammable, explosive and gasified cryogenic liquid ethylene adopt imported products basically. Even so it occurs operational failure that produces a serious iMPact on the device. Accordingly, it is so urgent for cryogenic vertical can pump localization.This article major in the normal trouble for cryogenic vertical can pump applications, especially for the key technology of pump. Conclusions are as follows:(1) It employs balance disc, radial vanes, first stage impeller that sinks, secondary impeller assembly that shifts as a whole, the joint spindle way of gib head key and spindle sleeve, secondary impeller components provided around the sliding bearing in structure.(2) Summarizing the selection condition of different API materials harden application conditions for surface hardening, welding of Cobalt Base Horniness Alloy, Chrome-plated metal surface.(3) Welding high self-lubricating chromium zirconium copper alloy powder on a 304 stainless steel using a semiconductor laser, resulting in good combination of substrate and surfacing layer and homogeneous and dense microstructures of surfacing layer.(4) Based on the liquid tube’s failure analysis of the practical application, pickling and passivation of submerged pump SS surface and control of welding heat input, the tendency of the intergranular corrosion decreased.