Calmes 是(shi)在改進(jin)方(fang)坯連鑄技(ji)術(shu)和水壓穿孔技(ji)術(shu)兩個方(fang)面技(ji)術(shu)的(de)基礎上而發展起PPM技(ji)術(shu)的(de)，在PPM發明(ming)之前解決連鑄坯穿孔問題的(de)幾個途徑(jing)主要是(shi)：
1. 將連鑄方坯軋(ya)(ya)成(cheng)圓(yuan)坯后，再用(yong)斜(xie)軋(ya)(ya)穿孔；
2. 采用三輥式穿孔機對低(di)碳鋼的連鑄坯穿孔，至于其(qi)他鋼種，則用經過軋制的連鑄坯進(jin)行穿孔；
3. 在水壓沖孔機上對(dui)連鑄(zhu)坯進行(xing)沖孔。
而(er)PPM可以直(zhi)接對(dui)連鑄方坯(pi)穿孔，這在技術發展(zhan)史(shi)上(shang)不能(neng)不說是一大進步。
A.H.Calmes 為發展壓力穿孔工藝而做的大量試驗始自20世紀50年代末，于60年代末制成試驗軋機，接著，在Dalmine 不銹鋼(gang)管廠(chang)進行了工業性試驗。
1971年(nian)意(yi)大利 Dalmine 廠建立了一個(ge)(ge)(ge)由(you)加(jia)熱到壓(ya)力(li)穿(chuan)(chuan)孔的(de)(de)(de)(de)完整(zheng)工(gong)業(ye)性試驗(yan)車間(jian)，試驗(yan)證明，壓(ya)力(li)穿(chuan)(chuan)孔工(gong)藝可以(yi)實現連鑄方坯的(de)(de)(de)(de)穿(chuan)(chuan)孔。所以(yi)，1978年(nian)8月(yue)在(zai)意(yi)大利Bergamo投產的(de)(de)(de)(de)世(shi)界上(shang)第一個(ge)(ge)(ge)MPM軋管廠采用了PPM,這臺壓(ya)力(li)穿(chuan)(chuan)孔機(ji)(ji)軋輥輥徑為1280mm,電機(ji)(ji)功率為500kW,推(tui)料機(ji)(ji)的(de)(de)(de)(de)最大推(tui)力(li)為2300kN.壓(ya)力(li)穿(chuan)(chuan)孔機(ji)(ji)前設有兩(liang)個(ge)(ge)(ge)導(dao)(dao)(dao)(dao)向(xiang)(xiang)裝置(zhi)(zhi)，一個(ge)(ge)(ge)是(shi)(shi)輥式(shi)(shi)導(dao)(dao)(dao)(dao)向(xiang)(xiang)裝置(zhi)(zhi)，另一個(ge)(ge)(ge)是(shi)(shi)板式(shi)(shi)導(dao)(dao)(dao)(dao)向(xiang)(xiang)裝置(zhi)(zhi)。后(hou)者是(shi)(shi)日(ri)本八(ba)幡廠滾動式(shi)(shi)導(dao)(dao)(dao)(dao)板裝置(zhi)(zhi)的(de)(de)(de)(de)一個(ge)(ge)(ge)改進(jin)，四塊導(dao)(dao)(dao)(dao)板各(ge)由(you)液壓(ya)缸壓(ya)向(xiang)(xiang)鋼(gang)坯，使方坯保持(chi)在(zai)中(zhong)心線上(shang)，壓(ya)力(li)穿(chuan)(chuan)孔機(ji)(ji)的(de)(de)(de)(de)推(tui)桿(gan)是(shi)(shi)一根圓棒，前端有一個(ge)(ge)(ge)方形(xing)推(tui)頭，在(zai)推(tui)桿(gan)的(de)(de)(de)(de)中(zhong)部有一個(ge)(ge)(ge)一段(duan)(duan)1m左(zuo)右的(de)(de)(de)(de)方形(xing)截面(mian)(mian)的(de)(de)(de)(de)導(dao)(dao)(dao)(dao)向(xiang)(xiang)段(duan)(duan)，在(zai)其四面(mian)(mian)鑲有可以(yi)更換(huan)的(de)(de)(de)(de)耐磨襯板。在(zai)推(tui)鋼(gang)時，這一段(duan)(duan)方形(xing)導(dao)(dao)(dao)(dao)向(xiang)(xiang)段(duan)(duan)不通過(guo)軋輥，而(er)只是(shi)(shi)在(zai)輥式(shi)(shi)導(dao)(dao)(dao)(dao)向(xiang)(xiang)裝置(zhi)(zhi)中(zhong)起導(dao)(dao)(dao)(dao)向(xiang)(xiang)作用。
壓力穿(chuan)(chuan)孔頂(ding)(ding)頭(tou)和頂(ding)(ding)桿(gan)(gan)擰在一(yi)(yi)起(qi)(qi)，穿(chuan)(chuan)孔結束后(hou)，頂(ding)(ding)桿(gan)(gan)連(lian)同空(kong)(kong)心(xin)坯一(yi)(yi)起(qi)(qi)橫向(xiang)移出到(dao)一(yi)(yi)條輥道上，在此擋住穿(chuan)(chuan)孔坯而將頂(ding)(ding)桿(gan)(gan)（及頂(ding)(ding)頭(tou)）抽出，穿(chuan)(chuan)孔后(hou)空(kong)(kong)心(xin)坯的壁(bi)(bi)厚不均(jun)平(ping)均(jun)為(wei)15%,經過一(yi)(yi)次延(yan)伸以后(hou)，空(kong)(kong)心(xin)坯的壁(bi)(bi)厚不均(jun)可減去70%.因此荒管(guan)的壁(bi)(bi)厚不均(jun)約(yue)為(wei)±5%,具體數據是(shi)：
對于壁厚為5.5~6.35mm的鋼管(guan)ΔS=±7%;
對于壁厚為15~18mm的鋼管(guan)ΔS=3.5%.
穿(chuan)(chuan)(chuan)孔(kong)(kong)(kong)(kong)(kong)(kong)(kong)后(hou)的(de)(de)(de)空(kong)心(xin)(xin)坯(pi)要在(zai)(zai)(zai)延(yan)(yan)伸(shen)機(ji)上(shang)(shang)(shang)延(yan)(yan)伸(shen)，減小管(guan)(guan)(guan)壁(bi)厚度，消除(chu)壁(bi)厚不(bu)(bu)均(jun)(jun)。在(zai)(zai)(zai)1961年(nian)(nian)進(jin)(jin)行(xing)旨在(zai)(zai)(zai)消除(chu)壁(bi)厚不(bu)(bu)均(jun)(jun)的(de)(de)(de)試(shi)(shi)(shi)驗，采用了如(ru)上(shang)(shang)(shang)所述的(de)(de)(de)結構(gou)(gou)方(fang)(fang)式。后(hou)的(de)(de)(de)1964~1965年(nian)(nian)在(zai)(zai)(zai)一臺16英(ying)寸(cun)(cun)(cun)周期(qi)軋(ya)管(guan)(guan)(guan)機(ji)上(shang)(shang)(shang)進(jin)(jin)行(xing)軋(ya)管(guan)(guan)(guan)試(shi)(shi)(shi)驗，其簡況如(ru)下(xia)：管(guan)(guan)(guan)坯(pi)為(wei)(wei)包括不(bu)(bu)銹鋼在(zai)(zai)(zai)內(nei)(nei)的(de)(de)(de)各(ge)種(zhong)鋼種(zhong)的(de)(de)(de)6~5/8英(ying)寸(cun)(cun)(cun)方(fang)(fang)鋼錠，穿(chuan)(chuan)(chuan)孔(kong)(kong)(kong)(kong)(kong)(kong)(kong)后(hou)空(kong)心(xin)(xin)坯(pi)的(de)(de)(de)外(wai)徑(jing)為(wei)(wei)8 1/4英(ying)寸(cun)(cun)(cun)，壁(bi)厚為(wei)(wei)2英(ying)寸(cun)(cun)(cun)，當L/I·D為(wei)(wei)12.5時，仍(reng)然(ran)可(ke)(ke)獲得(de)壁(bi)厚均(jun)(jun)勻的(de)(de)(de)空(kong)心(xin)(xin)坯(pi)。在(zai)(zai)(zai)1966年(nian)(nian)開始設計(ji)、制造工藝性試(shi)(shi)(shi)驗的(de)(de)(de)壓(ya)力(li)穿(chuan)(chuan)(chuan)孔(kong)(kong)(kong)(kong)(kong)(kong)(kong)機(ji)，在(zai)(zai)(zai)1969年(nian)(nian)制成試(shi)(shi)(shi)驗用的(de)(de)(de)壓(ya)力(li)穿(chuan)(chuan)(chuan)孔(kong)(kong)(kong)(kong)(kong)(kong)(kong)機(ji)，所穿(chuan)(chuan)(chuan)孔(kong)(kong)(kong)(kong)(kong)(kong)(kong)的(de)(de)(de)空(kong)心(xin)(xin)坯(pi)外(wai)徑(jing)為(wei)(wei)10~16 1/2英(ying)寸(cun)(cun)(cun)。鑒(jian)于采用連鑄(zhu)方(fang)(fang)坯(pi)生產無縫鋼管(guan)(guan)(guan)的(de)(de)(de)重(zhong)要意義(yi)，將1968年(nian)(nian)試(shi)(shi)(shi)驗計(ji)劃的(de)(de)(de)重(zhong)點放在(zai)(zai)(zai)連鑄(zhu)坯(pi)的(de)(de)(de)穿(chuan)(chuan)(chuan)孔(kong)(kong)(kong)(kong)(kong)(kong)(kong)上(shang)(shang)(shang)，接著采用各(ge)種(zhong)鋼種(zhong)，特別是在(zai)(zai)(zai)斜軋(ya)穿(chuan)(chuan)(chuan)孔(kong)(kong)(kong)(kong)(kong)(kong)(kong)機(ji)上(shang)(shang)(shang)難(nan)以穿(chuan)(chuan)(chuan)孔(kong)(kong)(kong)(kong)(kong)(kong)(kong)的(de)(de)(de)鋼種(zhong)，進(jin)(jin)行(xing)了大量的(de)(de)(de)壓(ya)力(li)穿(chuan)(chuan)(chuan)孔(kong)(kong)(kong)(kong)(kong)(kong)(kong)試(shi)(shi)(shi)驗，其結果如(ru)下(xia)：9 1/2英(ying)寸(cun)(cun)(cun)連鑄(zhu)方(fang)(fang)坯(pi)，經過(guo)加熱、定心(xin)(xin)、定型和清除(chu)氧化鐵皮(pi)后(hou)，在(zai)(zai)(zai)壓(ya)力(li)穿(chuan)(chuan)(chuan)孔(kong)(kong)(kong)(kong)(kong)(kong)(kong)機(ji)穿(chuan)(chuan)(chuan)成空(kong)心(xin)(xin)坯(pi)，其外(wai)徑(jing)為(wei)(wei)11 3/4英(ying)寸(cun)(cun)(cun)，內(nei)(nei)徑(jing)為(wei)(wei)6英(ying)寸(cun)(cun)(cun)，方(fang)(fang)坯(pi)穿(chuan)(chuan)(chuan)孔(kong)(kong)(kong)(kong)(kong)(kong)(kong)時的(de)(de)(de)延(yan)(yan)伸(shen)系數(shu)為(wei)(wei)1.08~1.18,通過(guo)軋(ya)輥孔(kong)(kong)(kong)(kong)(kong)(kong)(kong)型以及出口(kou)導套(tao)的(de)(de)(de)變換，可(ke)(ke)以改變空(kong)心(xin)(xin)坯(pi)的(de)(de)(de)外(wai)徑(jing)和延(yan)(yan)伸(shen)系數(shu)。當延(yan)(yan)伸(shen)系數(shu)為(wei)(wei)1.10時所得(de)的(de)(de)(de)結果為(wei)(wei)最(zui)好，截(jie)面(mian)也較(jiao)圓(yuan)。但應指(zhi)出，壓(ya)力(li)穿(chuan)(chuan)(chuan)孔(kong)(kong)(kong)(kong)(kong)(kong)(kong)法的(de)(de)(de)目的(de)(de)(de)并不(bu)(bu)在(zai)(zai)(zai)于獲得(de)完全圓(yuan)的(de)(de)(de)空(kong)心(xin)(xin)坯(pi)和較(jiao)巨大的(de)(de)(de)延(yan)(yan)長率，而是在(zai)(zai)(zai)不(bu)(bu)使(shi)金(jin)屬結構(gou)(gou)受到(dao)不(bu)(bu)利的(de)(de)(de)應力(li)狀(zhuang)態下(xia)，將方(fang)(fang)形鑄(zhu)坯(pi)穿(chuan)(chuan)(chuan)孔(kong)(kong)(kong)(kong)(kong)(kong)(kong)成為(wei)(wei)內(nei)(nei)表面(mian)質量良好的(de)(de)(de)圓(yuan)形空(kong)心(xin)(xin)坯(pi)，最(zui)大的(de)(de)(de)穿(chuan)(chuan)(chuan)孔(kong)(kong)(kong)(kong)(kong)(kong)(kong)比(bi)(bi)L/I·D可(ke)(ke)達24,而在(zai)(zai)(zai)水壓(ya)沖(chong)孔(kong)(kong)(kong)(kong)(kong)(kong)(kong)機(ji)上(shang)(shang)(shang)，穿(chuan)(chuan)(chuan)孔(kong)(kong)(kong)(kong)(kong)(kong)(kong)比(bi)(bi)僅為(wei)(wei)6,若其后(hou)設置延(yan)(yan)伸(shen)機(ji)，也只能達到(dao)9，在(zai)(zai)(zai)壓(ya)力(li)穿(chuan)(chuan)(chuan)孔(kong)(kong)(kong)(kong)(kong)(kong)(kong)機(ji)上(shang)(shang)(shang)，雖然(ran)L/I·D值很高，但其壁(bi)厚的(de)(de)(de)偏(pian)差仍(reng)在(zai)(zai)(zai)允許范圍內(nei)(nei)。
除了(le)加熱均勻(yun)與(yu)否(fou)以(yi)外，影(ying)響壁厚(hou)不均程度(du)的主要因(yin)素(su)是(shi)：
1. 設計方面的(de)因素 入口導套、出口導套、軋(ya)輥孔型、頂桿的(de)中心要在一條直線上；
2. 工(gong)具(ju)(ju)方面的因素 要將穿孔工(gong)具(ju)(ju)的公差值(zhi)減至最小；
3. 定心問題 在方坯的(de)(de)前端要有一(yi)個(ge)準確(que)的(de)(de)中心孔(kong)；
4. 穿孔頂頭和(he)頂桿的強度問題 當方坯加熱溫度為2300~2360 ℉時，頂桿的單位載荷不應超過65kg/m㎡.
