Over decades, LDPE plants were equipped with pneumatic operated control valves. Due to component aging and missing support of original equipment manufacturers, operators are facing serious problems especially regarding the maintenance of Let-Down valves. Over the years, UHPT has developed an optimized replacement solution for meeting operator’s requirements particularly with regard to accuracy of controlling the process and existing constraints within the plant. This solution has been implemented successfully and concerns about maintaining the process, design support as well as spare parts supply have been resolved.