液壓貨梯http://m.meilijh.com/的使用率越來越普遍,,由于各地區(qū)之間的溫差變化太大,,我國很多地區(qū)因氣溫過低給升降貨梯的使用帶來極大的不便,為滿足液壓貨梯能在低溫下正??煽康剡\行,,因此在設計和制造高空作業(yè)平臺時應著重解決以下幾個問題。
1,、低溫對液壓貨梯機件的脆性破壞,,低溫脆性破壞取決于材料、設計和工藝三個因素的綜合作用,。當溫度降低時其屈服點增高,,斷裂韌度降低,而屈強比的增大和塑性,、韌性的降低,,起裂前的塑性變形量和起裂后裂紋擴展的阻力減小,導致機件的脆化趨勢增加,;設計出現截面的突變,、應力與應變集中、缺口,、多軸拉應力狀態(tài)等,;工藝出現焊接裂紋、未熔合,、顯微組織的惡化,、殘余拉應力等,。
Low hydraulic freight elevator parts of brittle fracture, low brittle fracture depends on the material, design and workmanship combined effect of three factors. When the temperature is increased to reduce its yield point, fracture toughness decreases, and the yield is increased and stronger than the plastic, a decrease in toughness, plastic deformation before fracture initiation and post-initiation of crack growth resistance is reduced, resulting in brittle parts tendency to increase; the design section of the mutation occurs, the stress and strain concentration, gap, multiaxial tensile stress status; craft appeared welding cracks, lack of fusion, the deterioration of the microstructure and residual tensile stress.
2、液壓貨梯低溫受力構件的焊接結構形式及焊接工藝,,焊接前零件須經噴丸處理,,去掉氧化層,清除油污和銹痕,,手工焊接要嚴格控制焊條的干燥程度,,焊條要經過烘干處理等。
Welded structure and welding technology of hydraulic freight elevator low force member before welding parts subject to shot peening, remove the oxide layer, removing grease and rust marks, hand soldering is necessary to strictly control the dryness of the electrode, the electrode to go through the drying process, etc.
3,、液壓貨梯http://m.meilijh.com/液壓油液壓油的粘度至關重要,,粘度過高,系統(tǒng)內部摩擦阻力增大,,壓力損失增多,,油溫上升過快,操作時動作滯后,,粘度過低,,泵的容積效率低,潤滑性能差,,零部件間運動摩擦阻力增大,。
Critical hydraulic freight elevator hydraulic oil viscosity hydraulic oil viscosity is too high, the internal system friction increases, an increase in pressure loss, the oil temperature rises too fast, when operating actions lag, low viscosity, low volumetric efficiency of the pump, lubricating properties the difference between the component motion friction increases.