尖頭千(qian)(qian)(qian)(qian)斤(jin)(jin)頂(ding)(ding)(ding)是(shi)一種(zhong)(zhong)用(yong)鋼性頂(ding)(ding)(ding)舉件作為(wei)工作裝置，通過頂(ding)(ding)(ding)部托座或底部托爪在(zai)行程(cheng)內(nei)頂(ding)(ding)(ding)升(sheng)(sheng)重(zhong)(zhong)物的輕小(xiao)起(qi)(qi)重(zhong)(zhong)設備。按結(jie)(jie)構(gou)特(te)征可分為(wei)齒條(tiao)千(qian)(qian)(qian)(qian)斤(jin)(jin)頂(ding)(ding)(ding)、螺旋(xuan)(xuan)千(qian)(qian)(qian)(qian)斤(jin)(jin)頂(ding)(ding)(ding)和(he)液(ye)壓千(qian)(qian)(qian)(qian)斤(jin)(jin)頂(ding)(ding)(ding)3種(zhong)(zhong)。千(qian)(qian)(qian)(qian)斤(jin)(jin)頂(ding)(ding)(ding)是(shi)一種(zhong)(zhong)起(qi)(qi)重(zhong)(zhong)高(gao)度(du)(du)小(xiao) (小(xiao)于(yu)1m)的 簡(jian)單的起(qi)(qi)重(zhong)(zhong)設備。它(ta)械(xie)式(shi)和(he)液(ye)壓式(shi)兩(liang)種(zhong)(zhong)。機械(xie)式(shi)千(qian)(qian)(qian)(qian)斤(jin)(jin)頂(ding)(ding)(ding)又(you)有齒條(tiao)式(shi)與(yu)螺旋(xuan)(xuan)式(shi)兩(liang)種(zhong)(zhong)，由于(yu)起(qi)(qi)重(zhong)(zhong)量小(xiao)，操作費力(li)，一般只(zhi)用(yong)于(yu)機械(xie)維(wei)修工作，在(zai)修橋過程(cheng)中不適用(yong)。液(ye)壓式(shi)千(qian)(qian)(qian)(qian)斤(jin)(jin)頂(ding)(ding)(ding)結(jie)(jie)構(gou)緊湊(cou)，工作平(ping)穩，有自鎖作用(yong)，故(gu)使用(yong)廣(guang)泛。其缺點是(shi)起(qi)(qi)重(zhong)(zhong)高(gao)度(du)(du)有限(xian)，起(qi)(qi)升(sheng)(sheng)速度(du)(du)慢。
尖(jian)頭千(qian)斤頂(ding)分為(wei)機械千(qian)斤頂(ding)和液(ye)(ye)壓(ya)千(qian)斤頂(ding)兩種(zhong)，原理(li)各(ge)(ge)有不同。從原理(li)上(shang)(shang)來說，液(ye)(ye)壓(ya)千(qian)斤頂(ding)所基(ji)于的(de)(de)(de)(de)原理(li)為(wei)帕斯(si)卡原理(li)，即(ji)：液(ye)(ye)體(ti)各(ge)(ge)處(chu)的(de)(de)(de)(de)壓(ya)強是一致的(de)(de)(de)(de)，這樣，在(zai)平衡的(de)(de)(de)(de)系(xi)統中，比較(jiao)小(xiao)的(de)(de)(de)(de)活(huo)塞上(shang)(shang)面施加(jia)的(de)(de)(de)(de)壓(ya)力比較(jiao)小(xiao)，而大的(de)(de)(de)(de)活(huo)塞上(shang)(shang)施加(jia)的(de)(de)(de)(de)壓(ya)力也比較(jiao)大，這樣能(neng)夠保持液(ye)(ye)體(ti)的(de)(de)(de)(de)靜止。
