Effective protection of linear guides plays an important role in prolonging the life of the guides. To this end, we summarize the following eight characteristics of lubricating oil for linear guides:

一、直線導軌的粘度：直線導軌潤滑脂通常用表觀粘度或相似粘度來表示，在說明潤滑脂的粘度時，必須指明溫度和剪切速度。可采用相似粘度指標來控制其低溫流動性和泵送性。

1. Viscosity of linear guideway: Linear guideway grease is usually expressed by apparent viscosity or similar viscosity. Temperature and shear speed must be specified when describing the viscosity of grease. Similar viscosity index can be used to control its low temperature fluidity and pumpability.

二、直線導軌的強度極限：直線導軌潤滑脂的強度極限是指引起試樣開始流動的所需較小切應力，又稱極限切應力。潤滑脂強度極限是溫度的函數，溫度越高脂的強度極限越小，溫度降低，脂的強度極限變大，它的大小取決于稠化劑的種類與含量，和制脂工藝條件也有一定的關系。

Strength Limit of Linear Guide: Strength Limit of Linear Guide Grease refers to the minimum shear stress, also known as the ultimate shear stress, which causes the sample to start flowing. The strength limit of grease is a function of temperature. The higher the temperature, the smaller the strength limit of grease, the lower the temperature, and the greater the strength limit of grease. The size of grease depends on the type and content of thickener, and also has a certain relationship with the technological conditions of grease making.

三、直線導軌的滴點：直線導軌潤滑脂在規定條件下達到一定流動性時的較低溫度稱為滴點。潤滑脂的滴點有助于鑒別潤滑脂類型和粗略估計潤滑脂的較高使用溫度，一般說來，對于皂基脂，其使用溫度應低于滴點20~30°C滴點越高，其耐熱性越好。

3. Dropping point of linear guideway: The lowest temperature of linear guideway grease when it reaches a certain fluidity under specified conditions is called dropping point. The dropping point of grease is helpful to distinguish the type of grease and roughly estimate the maximum operating temperature of grease. Generally speaking, for soap grease, the higher the dropping point is, the better the heat resistance is.

四、直線導軌的膠體安定性：直線導軌潤滑脂的膠體安定性是指潤滑脂在一定溫度和壓力下保持膠體結構穩定，防止潤滑油從潤滑脂中析出的性能，也就是潤滑脂抵抗分油的能力。通常把潤滑脂析出油的數量換算為質量分數來表示。潤滑脂的膠體安定性反應出潤滑脂在長期儲存中與實際應用時分油趨勢，如果潤滑脂的膠體安定性差，則在受熱、壓力、離心力等作用下易下發生嚴重分油，導致壽命迅速降低，并使潤滑脂變稠變干，失去潤滑作用。

4. Colloidal Stability of Linear Guideway: Colloidal Stability of Linear Guideway Grease refers to the ability of lubricating grease to keep colloidal structure stable at a certain temperature and pressure and to prevent lubricating oil from precipitating from grease, that is, the ability of lubricating grease to resist oil separation. Usually the amount of oil released from grease is converted to the mass fraction. Colloidal stability of grease reflects the trend of oil in long-term storage and practical application. If the colloidal stability of grease is poor, serious oil distribution will occur under the action of heat, pressure and centrifugal force, which will lead to a rapid decrease in life and make grease thicker and drier, thus losing lubrication.

五、直線導軌的氧化安定性：氧化安定性是指潤滑脂在長期儲存或長期高溫下使用時抵抗熱和氧的作用，保持其性質不發生變化的能力。由于氧化，往往發生游離堿含量降低或游離有機酸含量增大，滴點下降，外觀顏色變深，出現異臭味，稠度、強度極限，相似粘度下降，生成腐蝕性產物和破壞潤滑脂結構的物質，造成皂油分離。因此，在潤滑脂長期儲存中，應存放在干燥通風的環境中，防止陽光曝曬，并應定期檢查游離堿或游離有機酸、腐蝕性等項目的變化，以保證其質量和使用性能。

Fifth, oxidation stability of linear guideway: oxidation stability refers to the ability of grease to resist heat and oxygen during long-term storage or long-term high temperature use, and to maintain its properties without permanent change. Owing to oxidation, the content of free alkali decreases or the content of free organic acid increases, dropping point decreases, appearance color becomes darker, odor, consistency, strength limit, similar viscosity decreases, corrosive products and substances destroying the structure of grease are formed, resulting in the separation of soap oil. Therefore, in the long-term storage of grease, it should be stored in a dry and ventilated environment to prevent sunlight exposure, and periodically check the changes of free alkali or free organic acid, corrosion and other items to ensure its quality and performance.

六、直線導軌的觸變性：直線導軌潤滑脂所具有的較基本的特性，就是觸變性。當施加一個外力時，潤滑脂的流動在逐漸變軟，表現粘度降低，但是一旦處于靜止，經過一段時間(很短)后，稠度再次增加(恢復)，這種特性稱為觸變性。潤滑脂的這種特性，決定了其可以在不適于潤滑油潤滑的部位潤滑，而顯示它優良的性能。

6. Thixotropy of linear guideway: Thixotropy is the most basic characteristic of linear guideway grease. When an external force is applied, the flow of grease gradually softens and the apparent viscosity decreases, but once at rest, after a period of time (very short), the consistency increases again (recovery), which is called thixotropy. This characteristic of grease determines that it can be lubricated in parts that are not suitable for lubricating oil and show its excellent performance.

七：直線導軌系統的固定元件(導軌)的基本功能如同軸承環，安裝鋼球的支架，形狀為“v”字形。支架包裹著導軌的頂部和兩側面。為了支撐機床的工作部件，一套直線導軌少有四個支架。用于支撐大型的工作部件，支架的數量可以多于四個。

Seventh: The basic function of the fixed elements (guideways) of the linear guideway system is like bearing rings, and the support with steel balls is in the shape of "v". The bracket covers the top and sides of the guide rail. In order to support the working parts of the machine tool, a set of linear guides has at least four supports. For supporting large working parts, the number of supports can be more than four.

八：直線導軌導軌系統的設計，力求固定元件和移動元件之間有較大的接觸面積，這不但能提高系統的承載能力，而且系統能承受間歇切削或重力切削產生的沖擊力，把作用力廣泛擴散，擴大承受力的面積。為了實現這一點，導軌系統的溝槽形狀有多種多樣，具有代表性的有兩種，一種稱為哥特式(尖拱式)，形狀是半圓的延伸，接觸點為頂點；另一種為圓弧形，同樣能起相同的作用。無論哪一種結構形式，目的只有一個，力求更多的滾動鋼球半徑與導軌接觸(固定元件)。決定系統性能特點的因素是：滾動元件怎樣與導軌接觸，這是問題的關鍵。

Eighth: The design of linear guideway system strives to maximize the contact area between fixed and mobile components, which can not only improve the bearing capacity of the system, but also withstand the impact force produced by intermittent cutting or gravity cutting, so that the force can be widely spread and the bearing area can be enlarged. In order to achieve this, the groove shape of the guideway system has many kinds, there are two representative types, one is called Gothic (pointed arch), the shape is the extension of the semi-circle, the contact point is the vertex; the other is circular arc, which can also play the same role. No matter which type of structure, there is only one purpose to make more contact between rolling ball radius and guide rail (fixed element). The key factor to determine the system performance characteristics is how the rolling element contacts the guide rail, which is the key to the problem.

直線導軌之所以有這么大的使用區域：1、直線導軌主要用在自動化機械上比較多,像德國進口的機床,紙碗機,激光焊接機等等,當然直線導軌和直線軸是配套用的。

Linear guides have such a large area of use: 1. Linear guides are mainly used in automation machinery, such as German imported machines, paper bowl machines, laser welding machines and so on. Of course, linear guides and straight axis are matched.
                            

2、直線導軌主要是用在精度要求比較高的機械結構上,直線導軌的移動元件和固定元件之間不用中間介質，而用滾動鋼球。因為滾動鋼球適應于高速運動、摩擦系數小、靈敏度高，滿足運動部件的工作要求，如機床的刀架，拖板等。如果作用在鋼球上的作用力太大，鋼球經受預加負荷時間過長，導致支架運動阻力增大。

2. Linear guideways are mainly used in mechanical structures with high precision requirements. Rolling steel balls are used instead of intermediate medium between moving and fixed components of linear guides. Because rolling steel ball is suitable for high-speed movement, small friction coefficient and high sensitivity, it meets the working requirements of moving parts, such as tool holder, trailer, etc. If the force acting on the steel ball is too large, the steel ball will endure the preload for too long, which will lead to the increase of the bracket resistance.