【正文】 fining iron ore in the steel smelting industry. Pellets is that the fine grinding essence of iron ore or other iron powder mixes a few additives, in the condition of water to wet, through Pelletier rolling into the ball, again after drying roasting, then it bee the spherical iron materials with strength and metallurgical properties. This paper introduces the basic structure of PLC and working principle , the hardware structure, instruction system, programming method of Siemens s7300 300/400 series PLC , and the use of STEP7 software. Through these knowledge, we design the feeding system of PLC control system in the production technology of pellets material introduces the PLC hardware configuration and software programming process, finally application simulation software PLCSIM to debug program. Keywords： Pellet production process、 PLC、 programming 共 2 頁(yè) 第 1 頁(yè) 目 錄 1 緒論 ......................................................................................................................... 1 球團(tuán)工藝的發(fā)展?fàn)顩r ............................................................................................ 1 球團(tuán)工藝簡(jiǎn)介 ........................................................................................................ 1 球團(tuán)基礎(chǔ)知識(shí) ................................................................................................. 1 球團(tuán)生產(chǎn)工藝 ................................................................................................. 2 本課題主要內(nèi)容 .................................................................................................... 3 2 PLC 控制系統(tǒng)設(shè)計(jì) ................................................................................................ 4 可編程控制器簡(jiǎn)介 ................................................................................................ 4 可編程控制器的基本結(jié)構(gòu) ............................................................................ 4 可編程控制器的工作原理 ............................................................................ 4 S7300 系列 PLC 簡(jiǎn)介 .......................................................................................... 5 S7300 的 CPU 模塊 ....................................................................................... 5 S7300 的輸入 /輸出模塊 ............................................................................... 6 S7300 的其他模塊 ......................................................................................... 7 供料系統(tǒng)硬件設(shè)計(jì) ................................................................................................ 7 系統(tǒng)硬件選型 ................................................................................................. 7 球團(tuán)生產(chǎn)線在 STEP7 中的硬件配置 .......................................................... 7 供料系統(tǒng) I/O 典型連接圖 ............................................................................. 8 3 西門(mén)子 STEP7 編程軟件 .................................................................................... 10 西門(mén)子 STEP7 編程軟件簡(jiǎn)介 ............................................................................ 10 S7300 用戶程序的模塊化結(jié)構(gòu) ......................................................................... 11 S7PLCSIM 仿真軟件 ......................................................................................... 12 4 供料系統(tǒng)程序設(shè)計(jì)流程 ...................................................................................... 14 程序說(shuō)明 ............................................................................................................... 14 供料系統(tǒng) 簡(jiǎn)介 ............................................................................................... 14 I/O 點(diǎn)說(shuō)明 ..................................................................................................... 16 供料程序設(shè)計(jì) ............................................................................................... 18 程序調(diào)試 ............................................................................................................... 22 共 2 頁(yè) 第 2 頁(yè) 總 結(jié) ................................................................................................................................... 26 致謝 ..................................................................................................................................... 27 參考文獻(xiàn) ............................................................................................................................. 28 附 錄 ................................................................................................................................... 29 順序控制程序 ................................................................................................................ 29 共 40 頁(yè) 第 1 頁(yè) 1 緒 論 球團(tuán)工藝的發(fā)展?fàn)顩r 由于天然 富礦 日趨減少，大量 貧礦 被采用；而鐵礦石經(jīng)細(xì)磨、選礦后的精礦粉，品位易于提高；過(guò)細(xì)精礦粉用于燒結(jié)生產(chǎn)會(huì)影響透氣性，降低產(chǎn)量和質(zhì)量；細(xì)磨精礦粉易于造球，粒度越細(xì)，成球率越高，球團(tuán)礦強(qiáng)度也越高。 如今球團(tuán)工藝的發(fā)展從單一處理鐵精礦粉擴(kuò)展到多種含鐵原料，生產(chǎn)規(guī)模和操作也向大型化、機(jī)械化、自動(dòng)化方向發(fā)展，技術(shù)經(jīng)濟(jì)指標(biāo)顯著提高 ，并要 努力趕上世界先進(jìn)水平。生球在爐內(nèi)經(jīng)過(guò)干燥、預(yù)熱、焙燒、均熱和冷卻等過(guò)程變成成品，由振動(dòng)給料機(jī)排放到鏈板機(jī)上，然后通過(guò)成品篩分機(jī)進(jìn)行篩分，粒徑 6mm 的成品球團(tuán)礦通過(guò)膠帶運(yùn)輸機(jī)經(jīng)計(jì)量后送入成品系統(tǒng)，粒徑 5mm 以下的小球和碎塊由 皮帶機(jī) 送 共 40 頁(yè) 第 3 頁(yè) 到返礦槽。然后根據(jù)這個(gè)結(jié)果刷新 I/O 印象區(qū)的狀態(tài)，排在下面的梯形圖，被刷新的邏輯線圈在下個(gè)掃描周期才對(duì)排在上面的程序起作用； 第三階段，輸出印象寄存器中存放的是 1，對(duì)應(yīng)繼電器的常開(kāi)觸點(diǎn)閉合，輸出印象寄存器中存放的是 0,對(duì)應(yīng)繼電器的常開(kāi)觸點(diǎn)斷開(kāi)。各 CPU 均有計(jì)數(shù)、頻率測(cè)量和脈沖寬度調(diào)制功能，有的有定位功能，有的帶有 I/O。直流輸入模塊操作電壓一般是 DC24