Surface texture and titanium nitride (TiN) coating have been established as effective methods for enhancing the tribological property of mechanical friction pairs. This study aims to investigate the tribological performance of dimple-textured surfaces with TiN coating under oil-lubricated conditions using a pin-on-disc wear experiment. Four types of pin samples with various end surfaces were designed, including bare rod samples, TiN-coated samples, textured samples, and TiN-coated/textured samples. The surface texture consists of a series of cylindrical micro-dimples with a diameter of 150 μm and a depth of 40 μm fabricated on the end surface of the pin. TiN coating treatment on the textured surface of the end face was performed by vacuum sputtering coating equipment. The study focuses on measuring and comparatively analyzing the friction coefficient, wear morphology, and binding force of the pin-disc friction pairs among the experiments. Compared with bare rod samples, TiN-coated/textured samples will reduce the friction coefficient (COF) of the pin-on-disc friction pair by at least 20% under oil-lubricated conditions in a 50 N normal contact load. The results indicate that the synergistic effect of dimple surface texture and TiN coating optimizes friction performance and reduces wear, highlighting the novelty of this study. Furthermore, the study identifies the hydrodynamic lubrication effect of the surface morphology formed by the dimple surface texture as a key factor in improving lubrication performance and reducing friction. Additionally, the dimple surface texture enables the mitigation of third body wear due to the wear debris storage function of the micro-dimples. This research provides valuable insights for the design and fabrication of mechanical friction pairs with high wear resistance under oil-lubricated conditions.

The operational stability and vibration performance of large-scale ventilation fans used in forestry storage facilities are critical for ensuring the safety and environmental control of timber and wood-based materials. To effectively reduce vibration levels and mitigate resonance risks, this study proposes a structural parameter optimization method that explicitly considers substructure uncertainty. By establishing an interval uncertainty optimization model, critical substructures and key structural parameters affecting natural frequencies were systematically identified. Structural parameters were optimized using response surface methodology to maximize the separation between the fan’s natural frequencies and its operating frequency, thereby reducing the likelihood of resonance. Experimental results validated a substantial reduction in vibration levels, confirming the method’s effectiveness in enhancing operational stability and prolonging the service life of these large-scale ventilation systems. This approach provides valuable insights and practical guidance for vibration control and reliability improvement of mechanical equipment in forestry storage and environmental control systems

Surface texture and titanium nitride (TiN) coating have been established as effective methods for enhancing the tribological properties of mechanical friction pairs. This work aims to investigate the lubrication performance of rhombic-textured TiN-coated surfaces under oil-lubricated conditions using a pin-on-disk test mode. A total of 17 sets of samples were designed, including a control sample (with no rhombic texture and no TiN coating), a TiN-coated sample and rhombic-textured TiN-coated samples. The rhombic surface texture was fabricated using the end surface of a brass bar. TiN coating deposited TiN on the textured surface. This study focuses on measuring and comparatively analyzing the lubrication load capacity, friction coefficient (COF) and binding force of TiN coatings/substrates in the pin-on-disk friction test mode. Compared with the bare control sample, a rhombic texture can enhance lubrication load-carrying capacity by generating hydrodynamic lubrication effects, thereby reducing friction. Additionally, a rhombic texture enables the mitigation of third-body wear due to wear debris. This research provides valuable insights into the design and fabrication of mechanical friction pairs with high wear resistance under oil-lubricated conditions. For lubrication property enhancement, the influence of groove depth was larger than that of the length of the rhombic side.

The whole-stalk harvesting and baling of reeds (Phragmites australis (Cav.) Trin. ex Steud) require a header with high efficiency and low loss rate. Based on an analysis of reed characteristic parameters, this paper proposes a T-shaped layout header design for whole-stalk reed harvesting. The design employs bilateral transverse conveying chains and a longitudinal clamping conveying chain, coordinated with a baler at its end, to achieve integrated harvesting and baling of whole reed stalks, thereby improving efficiency. By analyzing the relationship between key header parameters, such as the height of the lifting lugs on the transverse conveying device, the speeds of the transverse and longitudinal conveying chains, and the forward speed of the header, and the posture of the reeds, the causes of header loss during reed harvesting with the T-shaped header are identified. On this basis, a set of design criteria for the key parameters of the T-shaped whole-stalk reed header is established. A T-shaped reed whole-stalk harvesting header was designed according to these criteria and tested in harvesting experiments with varying preset values for forward speed and lower transverse conveying chain speed. Experimental data show that under optimally matched parameters, the header achieves a low average loss rate (L_h ≤ 2.0%) and a high average harvesting efficiency at the rated forward speed (up to 1.0 hm²/h, including baling), verifying the correctness of the theoretical analysis and the design criteria. The research results provide theoretical and experimental support for the design of conveying systems in headers for tall-stalk crops such as reeds.