Automated system for work preparation of parts production by sheet stamping

The procedure of automated process reliability evaluation is developed in order to prevent recurrent defects in parts manufactured by die stamping. The procedure is based on the analysis of such factors as part design, material, its mechanical and physical properties; equipment parameters, tool performance, etc. The list of reliability factors may vary according to type of operation as deformation process is different for each group of operations. The adjustment of stamping process reliability performance prevents any defects emerging during production of critical parts as early as the work preparation stage.

Abdominal wall augmentation techniques used in complex postincisional hernias repair

One of the most common unwanted consequence of abdominal surgery is the development of an incisional hernia. It occurs in up to 20% or more of laparotomies [1], [2]. Complex defects of the abdominal wall may also be caused by infection, trauma or tumor resection [3]. Complex and recurrent defects of the abdominal wall represents a challenging surgical and a socio-economic problem due to the time and material expenses [2]. Besides the aesthetic disfigurement those defects may also lead to functional consequences with poor protection of the intra-abdominal viscera [4]. Various surgical approaches can be used in hernia repair in an open fashion or minimally invasive laparoscopic or robotic techniques. Mesh herniorrhaphy was demonstrated to be superior to suture repair alone, with a recurrence rate of 32% compared with 63% in long-term follow-up, in spite of the advances made in mesh materials, surgical technique and perioperative care [1]. Regardless the approach, the tension-free repair remain the basis of modern herniology [5].

Examining the Effect of Alignment of the Rotor of the Emissions Exhaust Fan on Its Operating Parameters

The paper describes research examining the trends in balancing rotary machines and the application of the sequence of steps in execution of the operational balancing of an impeller of the industrial furnace emissions fan. The balancing process is based on the correction of the weight distribution of the body with the given axis of rotation. In trial operation, vibrations (with the measurement of the oscillation phase) were measured on both emission fan rotor bearings. Since the measured vibration value was higher than recommended, it was necessary to take steps to balance the fan’s impeller. The first step of the operational balancing is to identify the initial vibration vector relative to the reference mark, arbitrarily located on the rotating wheel of the fan. In trial operation, the balancing weight mass was changed in the selected balancing level, resulting in the change of the vibration vector compared to the initial state. The size and the angular position of the balancing weight were determined from the vibration values measured. 15 months into operation after the impeller was balanced, the diagnosis of its current technical condition was performed. Total vibrations of the device were measured in the low- and high-frequency range, at four measuring points on the rotor and the drive engine. The measurement confirmed a satisfactory technical condition of the engine and the fan equipment. The effect of balancing has also been demonstrated in the case observed. Reduced bearing wear, elimination of recurrent defects, foundation damage, etc., have been observed.