Vacuum Carburizing in a Pit Furnace: A 21st Century Solution to Large Component Case Hardening

Low pressure carburizing (LPC) is a proven, robust case hardening process whose potential is only limited by the style and size of vacuum furnace. Today, LPC is typically used in horizontal vacuum furnaces where the opportunity to carburize large parts is limited. In this paper we present a new adaptation of the technology in large pit type vacuum furnaces, capable of opening to air at elevated temperature. This underscores the potential of LPC to carburize larger, more massive parts in a clean, effective and efficient process. The result is quality casehardened parts without the undesirable side effects of atmosphere gas carburizing such as the use of a flammable atmosphere, reduced CO and NOx emissions, no intergranular oxidation, and limited retort life. Another significant advantage is decreased process time. The case study presented here shows that eliminating furnace conditioning and increasing process temperature can significantly reduce cycle durations by nearly three times and cut utility costs in half. Under these conditions, a return on investment (ROI) is in the neighborhood of 1 – 2 years is possible, making LPC in a pit style furnace a cost-effective solution than traditional atmosphere gas carburizing technologies.

Program of Integrated Care for Patients with Chronic Obstructive Pulmonary Disease and Multiple Comorbidities (PIC COPD+): a randomised controlled trial

We sought to evaluate the effectiveness of a multi-component, case manager-led exacerbation prevention/management model for reducing emergency department visits. Secondary outcomes included hospitalisation, mortality, health-related quality of life, chronic obstructive pulmonary disease (COPD) severity, COPD self-efficacy, anxiety and depression.Two-centre randomised controlled trial recruiting patients with ≥2 prognostically important COPD-associated comorbidities. We compared our multi-component intervention including individualised care/action plans and telephone consults (12-weekly then 9-monthly) with usual care (both groups). We used zero-inflated Poisson models to examine emergency department visits and hospitalisation; Cox proportional hazard model for mortality.We randomised 470 participants (236 intervention, 234 control). There were no differences in number of emergency department visits or hospital admissions between groups. We detected difference in emergency department visit risk, for those that visited the emergency department, favouring the intervention (RR 0.74, 95% CI 0.63–0.86). Similarly, risk of hospital admission was lower in the intervention group for those requiring hospital admission (RR 0.69, 95% CI 0.54–0.88). Fewer intervention patients died (21 versus 36) (HR 0.56, 95% CI 0.32–0.95). No differences were detected in other secondary outcomes.Our multi-component, case manager-led exacerbation prevention/management model resulted in no difference in emergency department visits, hospital admissions and other secondary outcomes. Estimated risk of death (intervention) was nearly half that of the control.