最新机械工程专业英语课件L09

respect to the hardware's stiffness.
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机械工程专业英语
Lesson 19 Screws, fasteners and joints
一、Background information
Theory
The results of this type of joint design are: Greater preloads in bolted joints reduce the fatigue loading of
When a cap screw is tightened it is stretched, and the parts that are captured are compressed. The result is a springlike assembly. External forces are designed to act on the parts that have been compressed, and not on the cap screw.
As long as the external loads on a joint don't exceed the clamp load, the hardware doesn't see any motion and will not come loose (no locking mechanisms are required).
六角头螺钉 双头螺柱头 圆柱头螺钉 盘头螺钉 沉头螺钉 圆柱头内六角螺
钉
Slotted cone pointed set screw. Hex nut. Slotted nut .
Bright washer.
锥端紧定螺钉 六角螺母 六角槽形螺母 平垫圈
Spring washer.
Tab washer
机械工程专业英语课件L09
机械工程专业英语
Lesson 19 Screws, fasteners and joints
Types of screw fasteners 螺纹紧固件的种类
Parts with threads used for joining and fastening are called screw fasteners. The most widely used components as screw fasteners are bolts, double screw bolts---stud, screws, nuts and washers。
compressed parts do not exceed the clamp load, the cap
screw do not see any increased load. This model is only valid
when the members under compression are much stiffer than
用螺纹联接并起紧固作用的零件称为螺纹紧固件。常用的螺 纹紧固件有螺栓、双头螺柱、螺钉、螺母、垫圈等。
Hexagon head bolt. Stud. Slotted cheese head screw. Slotted pan head screw. Slotted countersunk screw. Hexagon socket cap
the cap screw.
This is a simplified model. In reality the bolt will see a
small fraction of the external load prior to it exceeding the
clamp load, depending on the compressed parts' stiffness with
the hardware. For cyclic loads, the bolt does not see the full amplitude of the
load. As a result, fatigue life can be increased or, if the material exhibits an endurance limit, extended indefinitely.
弹簧垫圈 外舌止动垫圈
Washer
垫圈
பைடு நூலகம்
弹簧垫圈 平垫圈
Washer are used to match the other screw fasteners. 垫圈 与其他螺纹件配合使用
机械工程专业英语
Lesson 19 Screws, fasteners and joints 一、Background information
Theory The clamp load, also called preload, of a cap screw is
created when a torque is applied, and is generally a percentage of the cap screw's proof strength. Cap screws are manufactured to various standards that define, among other things, their strength and clamp load. Torque charts are available that identify the required torque for cap screws based on their property class or grade.
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机械工程专业英语
Lesson 19 Screws, fasteners and joints 一、Background information
Theory
The result is a non-intuitive distribution of strain; in this
engineering model, as long as the forces acting on the