Linear bearing can be divided into metal linear bearing and plastic linear bearing according to different materials. Linear bearing is used with quenched linear drive shaft. A system of infinite linear motion. Because of the point contact between the load ball and the quenching drive shaft, the allowable load is small, but when moving in a straight line, the friction resistance is the minimum, the precision is high and the movement is fast. But in the process of use, it often leads to the failure of linear bearing, how is this going on? The specific reasons are described in detail below.

直線軸承失效的主要三大原因：

There are three main reasons for the failure of linear bearing

1、磨損失效

1. Wear failure

磨損失效系指表面之間的相對滑動摩擦導致其工作表面金屬不斷磨損而產(chǎn)生的失效。IKO直線軸承、持續(xù)的磨損將引起直線軸承零件逐漸損壞，并更終導致直線軸承尺寸精度喪失及其它相關(guān)問題。磨損可能影響到形狀變化，配合間隙增大及工作表面形貌變化，可能影響到潤滑劑或使其污染達到一定程度而造成潤滑功能完全喪失，因而使直線軸承喪失旋轉(zhuǎn)精度乃不能正常運轉(zhuǎn)。磨損失效是各類軸承常見的失效模式之一，按磨損形式通常可分為更常見的磨粒磨損和粘著磨損。

Wear failure refers to the failure caused by the continuous wear of the metal on the working surface caused by the relative sliding friction between the surfaces. IKO linear bearing and other linear bearing will be damaged gradually. The wear may affect the shape change, the increase of fit clearance and the change of the working surface morphology, which may affect the lubricant or make it pollute to a certain extent, resulting in the complete loss of the lubrication function, so that the linear bearing loses the rotating accuracy and even can not operate normally. Wear failure is one of the common failure modes of all kinds of bearings, which can be divided into the most common abrasive wear and adhesive wear.

磨粒磨損系指直線軸承工作表面之間擠入外來堅硬粒子或硬質(zhì)異物或金屬表面的磨屑且接觸表面相對移動而引起的磨損，常在軸承工作表面造成犁溝狀的擦傷。硬質(zhì)粒子或異物可能來自主機內(nèi)部或來自主機系統(tǒng)其它相鄰零件由潤滑介質(zhì)送進直線軸承內(nèi)部。直線軸承精度誤差的相關(guān)知識。粘著磨損系指由于摩擦表面的顯微凸起或異物使摩擦面受力不均，在潤滑條件嚴重惡化時，因局部摩擦生熱，易造成摩擦面局部變形和摩擦顯微焊合現(xiàn)象，嚴重時表面金屬可能局部熔化，接觸面上作用力將局部摩擦焊接點從基體上撕裂而增大塑性變形。這種粘著——撕裂——粘著的循環(huán)過程構(gòu)成了粘著磨損，一般而言，輕微的粘著磨損稱為擦傷，嚴重的粘著磨損稱為咬合。

Abrasive wear refers to the wear caused by the relative movement of the contact surface between the working surfaces of linear bearing, which is caused by the external hard particles or hard foreign matters or metal surface and the relative movement of the contact surface. Hard particles or foreign matters may come from the main engine or other adjacent parts of the host system, which are sent into the linear bearing by lubricating medium. Linear bearing accuracy error related knowledge. Adhesive wear refers to the uneven stress on the friction surface caused by micro protrusion or foreign matters on the friction surface. When the lubrication conditions are seriously deteriorated, local deformation of the friction surface and friction micro welding phenomenon are easy to occur due to local friction. In severe cases, the surface metal may be partially melted, and the force on the contact surface will tear the local friction welding point from the matrix and increase the plastic deformation. This cycle of adhesion tear adhesion constitutes adhesive wear. Generally speaking, slight adhesive wear is called scuffing, and severe adhesive wear is called bite.

2、接觸疲勞失效

2. Contact fatigue failure

接觸疲勞失效系指直線軸承工作表面受到交變應力的作用而產(chǎn)生失效。接觸疲勞剝落發(fā)生在直線軸承工作表面，往往也伴隨著疲勞裂紋，從接觸表面以下交變切應力處產(chǎn)生，然后擴展到表面形成不同的剝落形狀，如點狀為點蝕或麻點剝落，剝落成小片狀的稱淺層剝落。由于剝落面的逐漸擴大，而往往向深層擴展，形成深層剝落。深層剝落是接觸疲勞失效的疲勞源。

Contact fatigue failure refers to the failure of linear bearing working surface under the action of alternating stress. Contact fatigue spalling occurs on the working surface of linear bearing, which is often accompanied by fatigue cracks. Firstly, it occurs at the maximum alternating shear stress below the contact surface, and then extends to the surface to form different spalling shapes, such as pitting corrosion or pitting spalling, and spalling into small flakes is called shallow spalling. Due to the gradual expansion of the spalling surface, it often extends to the deep layer, forming deep spalling. Deep spalling is the fatigue source of contact fatigue failure.

3、斷裂失效

3. Fracture failure

直線軸承斷裂失效主要原因是缺陷與過載兩大因素。當外加載荷超過材料強度極限而造成零件斷裂稱為過載斷裂。過載原因主要是主機突發(fā)故障或安裝不當。軸承零件的微裂紋、縮孔、氣泡、大塊外來雜物、過熱組織及局部燒傷等缺陷在沖擊過載或劇烈振動時也會在缺陷處引起斷裂，稱為缺陷斷裂。應當指出，直線軸承在制造過程中，對原材料的入廠復驗、鍛造和熱處理質(zhì)量控制、加工過程控制中可通過儀器正確分析上述缺陷是否存在，今后仍必須加強控制。但一般來說，通常出現(xiàn)的直線軸承斷裂失效大多數(shù)為過載失效。

The main reason of linear bearing fracture failure is defect and overload. When the external load exceeds the material strength limit, the part fracture is called overload fracture. The main cause of overload is the sudden failure of the host or improper installation. The defects of bearing parts such as microcracks, shrinkage cavities, bubbles, large pieces of foreign debris, overheated tissue and local burns will also cause fracture at the defects when the impact overload or severe vibration occurs, which is called defect fracture. It should be pointed out that the above defects can be correctly analyzed by instruments in the factory re inspection of raw materials, quality control of forging and heat treatment, and control of processing process in the manufacturing process of linear bearings, and the control must be strengthened in the future. But generally speaking, most of the fracture failure of linear bearing is overload failure.

目前，直線軸承被越來越廣泛的運用到電子設備、食品機械、包裝機械、醫(yī)療機械、印刷機械、紡織機械、機械、儀器、機器人、工具機械、數(shù)控機床、汽車及數(shù)字化三維坐標測量設備等精密設備或特殊機械行業(yè)之中。

At present, linear bearing is more and more widely used in electronic equipment, food machinery, packaging machinery, medical machinery, printing machinery, textile machinery, machinery, instruments, robots, tool machinery, CNC machine tools, automobiles and digital three-dimensional coordinate measuring equipment and other precision equipment or special machinery industry.