Todays Chemical-LNG/LPG-ships moving millions og tons og dangerous Chemicals and Gas around the world. Serving Industrial-plants, Refinieries and Oil/gas-terminals.
These ships have not being so often in the newsspot, linked to accidents as their bigger cusins VLLC’s.
Luckily so, when the fluids are much more dangerous and toxic than crude oil.
The have been from many years designed with top safety procedures, specifications incl. materials with Appoval from IMO and Classification Authoritys. The Cargo Systems w/segregation of all secondary tanks in loading/unloading situation have contributed to a low accidental statistics during many years. With existing and new chemicals (caustic s., oxides a.o) entering the market, this will put extra pressure on the components like valves, pumps, pipes and jointings.Most of the specifications are from over 20years ago regarding stainless materials, jointings and Maintance tools.
When we today still use AISI 316L Stainless in mentioned components (IMO II&III) we now, with all the new chemicals/gases should consider to level up this material to at AISI 317L w/min 3% Mo, withstanding Corrosion/oxidizing from these mentioned new chemicals and gases. Also the Jointings/gaskets should be upgraded from today pure PTFE (Teflon) to Re-inforced PTFE (KEMFLON) w/75% PTFE and 25% GRP making these gaskets much stronger against wear and tear from mentioned chemical and Operation of the components. The effect of a sudden leak at high pressure on a valve in the cargo system in a loading/unloading situation can be rather dramatic for the operating crew and to the environment.
After serving as Machine Engineer onboard VLCC ‘s and Chemical tankers IMO Class II&III for several years back in 1980’s and later as Production Manager for valve-production in SEUT Industrier and today C E O in SEUT Maritime as, I got these problems on my table very often caused from sub-standard materials in valves and jointings. In SEUT Maritime we already in 1995 upgraded all materials in valves and jointings to above high specifications. I take a lot of interest in follow the installation onboard newbuildings world wide, hands on and keeping in tuch with Chief Engineers after.I will point to the pictures showing me in action of testing(w/nitrogen- 40bar) a LPG Cargo System on a newbuilding at Kawasaki Shipbuiding Corp., Sakaide, Japan, using SEUT Cargo Valves w/ AISI 317L material fitted w/KEMFLONJointings. Next picture shows our newest Valve in same material s w/ Pressure Indicator, Bleeding/Sample Connection making control and maintance much more predictable. I therefore hope that this will be the state of the art on mentioned Ship-types, FPSO’s, Refinireys and Oil/gas terminals in the near future.
