相关试题
【判断题】
气焊是利用气体火焰加热并熔化母体材料和焊丝的焊接方法
【判断题】
气焊常用于薄板的低碳钢、低合金钢、不锈钢的对接、端接，在熔点较低的铜、铝及其合金的焊接中仍有应用
【判断题】
中性焰是当氧气与乙炔的混合比为 1～1.2 时，燃烧充分，燃烧过后无剩余氧或乙炔，热量集中，温度可达 2050℃～2150℃
【判断题】
中性焰焰心是呈亮白色的圆锥体，温度较低；内焰呈暗紫色，温度最高，适用于焊接；外焰颜色从淡紫色逐渐向橙黄色变化，温度下降，热量分散
【判断题】
碳化焰是指当氧气与乙炔的混合比小于 1 时，部分乙炔未曾燃烧，焰心较长，呈蓝白色，温度最高达 2700℃～3000℃
【判断题】
氧化焰是指当氧气与乙炔的混合比大于 1.2时，燃烧过后的气体仍有过剩的氧气，焰心短而尖，内焰区氧化反应剧烈，火焰挺直发出“嘶嘶”声，温度可达 2100℃～2300℃
【判断题】
氧化焰由于火焰具有氧化性，焊接碳钢易产生气体，并出现熔池沸腾现象，很少用于焊接
【判断题】
电阻焊是将零件组合后通过电极施加压力，利用电流通过零件的接触面及临近区域产生的电阻热将其加热到熔化或塑性状态，使之形成金属结合的方法
【判断题】
点焊方法：将零件装配成搭接形式，用电极将零件夹紧并通以电流，在电流热作用下，电极之间零件接触处被加热熔化形成焊点
【判断题】
凸焊 是电加热后突起点被压塌，形成焊接点的电阻焊方法
【判断题】
对焊工作原理：将两零件端部相对放置，加压使其端面紧密接触，通电后利用电阻热加热零件接触面至塑性状态，然后迅速施加大的顶锻力完成焊接
【判断题】
电渣焊是一种利用电流通过液体熔渣所产生的电阻热加热熔化填充金属和母材，以实现金属焊接的熔化焊接方法
【判断题】
电渣焊适用于厚板、大断面、曲面结构的焊接，如火力发电站数百吨的汽轮机转子、锅炉大厚壁高压汽包等
【判断题】
激光焊是利用大功率相干单色光子流聚集而成的激光束为热源进行焊接的方法
【判断题】
焊接时，焊件仅在局部区域被加热到高温，离焊缝愈远，温度愈高，膨胀也愈大
【判断题】
焊接产生拉应力和压应力，当这些应力超过金属的强度极限时，将产生焊接变形；当超过金属的屈服极限时，则会出现裂缝
【判断题】
未焊透是指工件与焊缝金属或焊缝层间局部未熔合的一种缺陷
【判断题】
裂纹是最危险的一种缺陷，它除了减少承载截面之外，还会产生严重的应力集中，在使用中裂纹会逐渐扩大，最后可能导致构件的破坏
【判断题】
孔加工刀具都应同时完成两个运动。主运动，即沿着轴线方向对着零件的直线运动；进给运动，即刀具刀具绕轴线的旋转运动
【判断题】
CO2 气体保护焊设备可分为手动焊和自动焊两种类型
【判断题】
以惰性气体氩气作保护气的电弧焊方法有钨极氩弧焊和熔化极氩弧焊两种
【判断题】
由于被惰性气体隔离，焊接区的熔化金属不会受到空气的有害作用，所以钨极氩弧焊可用以焊接易氧化的有色金属如铝、镁及其合金
【判断题】
埋弧焊电弧产生于堆敷了一层的焊剂下的焊丝与零件之间，受到熔化的焊剂—熔渣以及金属蒸汽形成的气泡壁所包围
【判断题】
埋弧焊主要优点是焊接电流和电流密度大，生产效率高，是手弧焊生产率的 1～2 倍
【判断题】
气焊是利用气体火焰加热并熔化母体材料和焊条的焊接方法
【判断题】
锯条一般用工具钢或合金钢制成，并经淬火和高温回火处理
【判断题】
锯条规格用锯条两端安装孔之间距离表示，并按锯齿齿距分为粗齿、细齿二种
【判断题】
锯齿在制造时按一定的规律错开排列形成锯路
【判断题】
安装锯条时，锯齿方向必须朝前，锯条绷紧程度要适当
【单选题】
移动式供气源呼吸器可单人使用，也可___使用。
A. 多人同时
B. 两人同时
C. 3 人同时
D. 4人同时
【单选题】
移动式供气源4个气瓶允许每次更换___个空瓶而不中断供气。
【单选题】
移动式供气源配置4个6升/20兆帕气瓶时，1人使用可用___小时。
【单选题】
电绝缘手套最高测试电压为___伏。
A. 500
B. 5000
C. 10000
D. 20000
【单选题】
防高温手套的耐热温度为___℃。
A. 450
B. 900
C. 1200
D. 2000
【单选题】
防护器材按使用场合分为常规防护装备和___防护装备。
【单选题】
消防安全钩应定期按___工作拉力作载荷检查。
A. 4500牛
B. 450牛
C. 45000牛
D. 45牛
【单选题】
空气呼吸器使用前气瓶压力不能低于___Mpa。
【单选题】
AHG-2型氧气呼吸器有效使用时间为___。
A. 30分钟
B. 1小时
C. 2小时
D. 6小时
【单选题】
___是消防员在灭火救援、抢险救灾中用于救人和自救的绳索，或用于日常训练。
A. 救生绳
B. 钢丝绳
C. 麻绳
D. 铁索
推荐试题
【填空题】
make it， with open arms ，strip off，keep back，
free of/ from ，after all，straighten up， throw away
I never really had any problems with change. On the contrary, I welcome change [ ]
【填空题】
make it， with open arms ，strip off，keep back，
free of/ from ，after all，straighten up， throw away
A lot of what we [ ] is made from raw materials which are not renewable
【填空题】
make it， with open arms ，strip off，keep back，
free of/ from ，after all，straighten up， throw away
Megan and John realized that their house was too messy for a new baby, so they decided to [ ] their house before the baby was born
【填空题】
make it， with open arms ，strip off，keep back，
free of/ from ，after all，straighten up， throw away
Jennifer couldn't [ ] her tears when she saw the sick children at a new blood cancer center in Virginia
【填空题】
make it， with open arms ，strip off，keep back，
free of/ from ，after all，straighten up， throw away
We want to give all children a world [ ] violence
【填空题】
advocate，involve，confine，respond，subsequent ，distinct ，intense， fulfill，circumstance， reconcile
Fortunately, the accident didn't [ ] many people, for there was little traffic at that hour.
【填空题】
advocate，involve，confine，respond，subsequent ，distinct ，intense， fulfill，circumstance， reconcile
She[ ] her ambition of becoming a fashion designer after years of hard work
【填空题】
advocate，involve，confine，respond，subsequent ，distinct ，intense， fulfill，circumstance， reconcile
They kept on trying their best to develop
their business, but in such [ ]market competition, they had no Idea if success would come along one day
【填空题】
advocate，involve，confine，respond，subsequent ，distinct ，intense， fulfill，circumstance， reconcile
As music plays an important role in our life, many music teachers and educators [ ] taking up a musical instrument at a young age
【填空题】
advocate，involve，confine，respond，subsequent ，distinct ，intense， fulfill，circumstance， reconcile
This rule should be entirely clear in the minds of everyone and should not be misunderstood under any [ ]
【填空题】
advocate，involve，confine，respond，subsequent ，distinct ，intense， fulfill，circumstance， reconcile
My daughter was shy; she was afraid to ask questions,[ ] to questions in class,or talk with other children
【填空题】
advocate，involve，confine，respond，subsequent ，distinct ，intense， fulfill，circumstance， reconcile
I got from him only a letter, which was put on my office desk; [ ] to the receipt of this letter I have never heard from him
【填空题】
advocate，involve，confine，respond，subsequent ，distinct ，intense， fulfill，circumstance， reconcile
The duties to provide services for children in need are not [ ] to the local social services department
【填空题】
advocate，involve，confine，respond，subsequent ，distinct ，intense， fulfill，circumstance， reconcile
We pray that all nations be [ ] and that all people around the world live in peace
【填空题】
controversial，assess， resolve，decrease，alter，abandon，indicate，undermine，compromise， conventional
It was reported the president had [ ]to fight If war was necessary,even if it meant destroying his chances of re-election
【填空题】
controversial，assess， resolve，decrease，alter，abandon，indicate，undermine，compromise， conventional
I had to [ ] one of my email accounts as it was filled with junk mail
【填空题】
controversial，assess， resolve，decrease，alter，abandon，indicate，undermine，compromise， conventional
Darwin's theory of evolution remains[ ] partly because it challenges the religious belief that God created man
【填空题】
advocate，involve，confine，respond，subsequent ，distinct ，intense， fulfill，circumstance， reconcile
He suggested a small but [ ] improvement on our former plan; I really appreciate it.
【填空题】
in sb. 's words，count on，make sense of ，reserve for， shield from，call on， sum up， relate to ，in need，
be/ get caught up in
She held her hand above her eyes to [ ]them [ ] the sun so that she could see more clearly the man in front of her
【填空题】
in sb. 's words，count on，make sense of ，reserve for， shield from，call on， sum up， relate to ，in need，
be/ get caught up in
The boy studied the signs for over an hour,but still could not [ ]them, so he turned to his teacher for help
【填空题】
in sb. 's words，count on，make sense of ，reserve for， shield from，call on， sum up， relate to ，in need，
be/ get caught up in
They [ ] the developed countries to commit more money to protecting the environment
【填空题】
in sb. 's words，count on，make sense of ，reserve for， shield from，call on， sum up， relate to ，in need，
be/ get caught up in
We will continue to care for those [ ] and work to establish a society that is generous and prosperous
【填空题】
in sb. 's words，count on，make sense of ，reserve for， shield from，call on， sum up， relate to ，in need，
be/ get caught up in
Many people [ ]careers and raising kids so that they forget that their marriages also need to be taken good care of
【填空题】
in sb. 's words，count on，make sense of ，reserve for， shield from，call on， sum up， relate to ，in need，
be/ get caught up in
My most favorite program is the one that deals with scientific subjects that ordinary people can [ ]
【填空题】
in sb. 's words，count on，make sense of ，reserve for， shield from，call on， sum up， relate to ，in need，
be/ get caught up in
Finally, I would like to [ ]by saying that it has been a tremendous pleasure to work with you all
【填空题】
in sb. 's words，count on，make sense of ，reserve for， shield from，call on， sum up， relate to ，in need，
be/ get caught up in
He is a person that you always [ ]when you need help.
【填空题】
in sb. 's words，count on，make sense of ，reserve for， shield from，call on， sum up， relate to ，in need，
be/ get caught up in
This restaurant is very popular because it has some separate, smaller rooms [ ] families with small children
【填空题】
in sb. 's words，count on，make sense of ，reserve for， shield from，call on， sum up， relate to ，in need，
be/ get caught up in
Betty loves reading.[ ],“Reading is the most wonderful thing in the world.”
【填空题】
open the door to，In advance，all at once，reap the benefits (of)， make the most of，over time， get by， stand a chance (of)，remind of， take pleasure in，
Every one of you has made a contribution and I [ ] knowledging what each of you has done to make this academic convention such a success.
【填空题】
open the door to，In advance，all at once，reap the benefits (of)， make the most of，over time， get by， stand a chance (of)，remind of， take pleasure in
They all tried to talk [ ], but I couldn't hear anything they said
【填空题】
open the door to，In advance，all at once，reap the benefits (of)， make the most of，over time， get by， stand a chance (of)，remind of， take pleasure in，
Yellow flowers in the field always [ ] me [ ] my childhood in the countryside
【填空题】
open the door to，In advance，all at once，reap the benefits (of)， make the most of，over time， get by， stand a chance (of)，remind of， take pleasure in，
We have been practicing for so long and so hard that our team should [ ]winning the game
【填空题】
open the door to，In advance，all at once，reap the benefits (of)， make the most of，over time， get by， stand a chance (of)，remind of， take pleasure in，
Research on genes will [ ] exciting new medical treatments.,
【填空题】
open the door to，In advance，all at once，reap the benefits (of)， make the most of，over time， get by， stand a chance (of)，remind of， take pleasure in，
My family [ ] on my father's unemployment benefit after he lost his job
【填空题】
open the door to，In advance，all at once，reap the benefits (of)， make the most of，over time， get by， stand a chance (of)，remind of， take pleasure in，
Many subway riders read books or listent music in order to [ ] their time on the way to work
【填空题】
open the door to，In advance，all at once，reap the benefits (of)， make the most of，over time， get by， stand a chance (of)，remind of， take pleasure in，
In order to make sure he would be able to attend the meeting, I called him up two weeks [ ]
【填空题】
open the door to，In advance，all at once，reap the benefits (of)， make the most of，over time， get by， stand a chance (of)，remind of， take pleasure in，
In order to [ ]physical exercise, you have to exercise regularly and for at least half an hour each time
【填空题】
embarrass，polish， emotional， etticiency，curb ，await， donation ，dump，stuff ，historical
Mary was a careful speaker, every word seemed to have been [ ] before it was allowed to escape through her lips
【填空题】
embarrass，polish， emotional， etticiency，curb ，await， donation ，dump，stuff ，historical
He has a special feeling for the brilliant birds, and each spring he eagerly [ ] their return
【填空题】
embarrass，polish， emotional， etticiency，curb ，await， donation ，dump，stuff ，historical
Thanks to the [ ] of air transport,everyone is free to go anywhere at any time
