焊接筆試題目-wenkub
2024-11-05 00 本頁面
【正文】 根據(jù)作業(yè)指導書要求選擇焊接工具與材料，如果是有鉛焊接我們應選擇焊臺，焊接錫線為，如果是無鉛焊接我們則應選擇焊臺，焊接錫線為。按目前產品，我們有鉛焊接點焊溫度為：，拖焊為：；無鉛點焊溫度為：，拖焊溫度為：；但針式咪頭焊接較為特殊，溫度規(guī)定為：。點焊焊接時間不能超過秒，拖焊時間不能超過秒。針對焊接點的不同，我們在選擇工具上也有相應的要求，點焊需選擇烙鐵頭，拖焊需選擇烙鐵頭。（）線頭裸露在空氣中易氧化侵蝕焊點內部，但不會影響焊接質量，造成隱患。（）當烙鐵頭輕微氧化時可以采用大量加錫——清洗——再加錫——再清洗的方式以去除氧化，對嚴重氧化的烙鐵頭予以更換后交設備課處理。s waited for a second and knew what I had to much as I wanted to be on Smart Aleck,Carla wanted __42 it __ even ,starting with my next question,I held back and let Carla __43 win __,just by a little expression as she __44 realized __ she would be on the show made up for my not being on the since I will go as backup,I39。t hurt the team because Carla will be a very good petitor on the real think that making my best friend happy was the right thing to 、A3D3C3C3AA4C4B4D4B4D4BBButterflies are mon all over the world，but butterflies in hotter countries are usually bigger and more brightly colored than those in coo1er countries，and there are more differentkinds．Usually the male(雄性的)butterflies are more brightly colored than the females．The females have bigger and heavier bodies since they carry the eggs．The bright colors of the males help toattract the females，and the duller(較暗淡的)colors of the females make them less likely(可能的)to be caught by enemies before they have laid their eggs． Some butterflies have bright pattern colors on the upper surface of their wings that show when flying ,but when they rest on a tree or leaves , they close their wings．On the undersides of their wings there are green and brown marks which look like the tree or leaves．They are then difficult to be seen．The best example of this is the Dead Leaf Butterfly．When its wings are c1osed，it looks exactly like a dead leaf．There are even marks that look like the holes in a dead leaf．When the butterfly is run after by a bird，it closes its wings and seems to havedisappeared pletely．Many butterflies have round marks on their wings that look like eyes．The round marks have a useful function(功能)．When the butterflies are resting，their wings are closed，and these marks can’t be a bird sees one，and begins to attack it，the butterfly will open
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