盲(mang)(mang)板(ban)(ban)（Blind）、8字(zi)盲(mang)(mang)板(ban)(ban)（Spectacle Blind； Figure 8 Blind）、插(cha)板(ban)(ban)（Paddle Blank）以及墊環(huan)（Paddle Spacer），制造方法一般分三種：鍛打、鑄鍛、中(zhong)板(ban)(ban)割制。其中(zhong)鍛打產品價格最高(gao)，中(zhong)板(ban)(ban)次之，鑄鍛最低(di)。而(er)質量是鍛打和中(zhong)板(ban)(ban)的好，鑄鍛的要稍差些(xie)。盲(mang)(mang)板(ban)(ban)或(huo)“8”字(zi)盲(mang)(mang)板(ban)(ban)與閥門相比，其關斷作用更(geng)可靠而(er)且更(geng)經(jing)濟。

  盲板(ban)(ban)、“8”字(zi)盲板(ban)(ban)、插板(ban)(ban)以及墊環(huan)都應有兩個和(he)匹配(pei)法蘭同樣的密封面(mian)。常用的密封面(mian)包含平(ping)面(mian)、凹凸面(mian)、榫槽面(mian)和(he)環(huan)連面(mian)。

  盲板（見圖4-15）用(yong)(yong)于(yu)(yu)起(qi)隔(ge)(ge)離(li)、切斷作用(yong)(yong)的(de)(de)，和(he)(he)封頭、管(guan)(guan)帽所起(qi)的(de)(de)作用(yong)(yong)是(shi)一樣的(de)(de)。由(you)于(yu)(yu)其密封性能好，對于(yu)(yu)需要完全(quan)隔(ge)(ge)離(li)的(de)(de)系統(tong)，一般都作為可靠的(de)(de)隔(ge)(ge)離(li)手段(duan)。盲板就是(shi)一個帶柄的(de)(de)實心(xin)的(de)(de)圓，用(yong)(yong)于(yu)(yu)通常狀況下處(chu)于(yu)(yu)隔(ge)(ge)離(li)狀態的(de)(de)系統(tong)。盲板的(de)(de)有(you)關(guan)標準，可參見HG/T 20592～20635《鋼制管(guan)(guan)法(fa)蘭、墊片、緊固(gu)件(jian)》和(he)(he)ASME B16.5《管(guan)(guan)法(fa)蘭和(he)(he)法(fa)蘭管(guan)(guan)件(jian)》。

  8字(zi)(zi)盲(mang)(mang)板(ban)(ban)(ban)（見(jian)圖4-16），形狀像“8”字(zi)(zi)，一端(duan)(duan)是(shi)盲(mang)(mang)板(ban)(ban)(ban)，另一端(duan)(duan)是(shi)節(jie)流(liu)環(huan)(huan)(huan)(huan)（墊(dian)(dian)環(huan)(huan)(huan)(huan)），但直徑與管(guan)(guan)道的(de)管(guan)(guan)徑相同，并不起節(jie)流(liu)作用(yong)(yong)(yong)。8字(zi)(zi)盲(mang)(mang)板(ban)(ban)(ban)，使用(yong)(yong)(yong)方便(bian)，需(xu)(xu)要(yao)(yao)隔離時(shi)，使用(yong)(yong)(yong)盲(mang)(mang)板(ban)(ban)(ban)端(duan)(duan)，需(xu)(xu)要(yao)(yao)正常操(cao)作時(shi)，使用(yong)(yong)(yong)節(jie)流(liu)環(huan)(huan)(huan)(huan)（墊(dian)(dian)環(huan)(huan)(huan)(huan)）端(duan)(duan)，同時(shi)也可用(yong)(yong)(yong)于(yu)(yu)(yu)填補管(guan)(guan)路(lu)上盲(mang)(mang)板(ban)(ban)(ban)的(de)安裝間隙。另一個(ge)特點(dian)就是(shi)標(biao)識明(ming)顯，易于(yu)(yu)(yu)辨認安裝狀態。主(zhu)要(yao)(yao)用(yong)(yong)(yong)于(yu)(yu)(yu)小于(yu)(yu)(yu)等于(yu)(yu)(yu)DN600的(de)管(guan)(guan)道系統。插板(ban)(ban)(ban)（見(jian)圖4-17）和(he)墊(dian)(dian)環(huan)(huan)(huan)(huan)（見(jian)圖4-18）互為盲(mang)(mang)通，和(he)8字(zi)(zi)盲(mang)(mang)板(ban)(ban)(ban)的(de)作用(yong)(yong)(yong)類(lei)似，主(zhu)要(yao)(yao)用(yong)(yong)(yong)于(yu)(yu)(yu)大(da)于(yu)(yu)(yu)DN600的(de)管(guan)(guan)道系統。8字(zi)(zi)盲(mang)(mang)板(ban)(ban)(ban)、插板(ban)(ban)(ban)和(he)墊(dian)(dian)環(huan)(huan)(huan)(huan)的(de)有(you)關標(biao)準，可參見(jian)HG/T 21547《管(guan)(guan)道用(yong)(yong)(yong)鋼制插板(ban)(ban)(ban)、墊(dian)(dian)環(huan)(huan)(huan)(huan)、8字(zi)(zi)盲(mang)(mang)板(ban)(ban)(ban)》、ASME B16.48 Steel Line Blanks（8字(zi)(zi)盲(mang)(mang)板(ban)(ban)(ban)、插板(ban)(ban)(ban)、墊(dian)(dian)環(huan)(huan)(huan)(huan)）、API 590Steel Line Blanks（8字(zi)(zi)盲(mang)(mang)板(ban)(ban)(ban)、插板(ban)(ban)(ban)、墊(dian)(dian)環(huan)(huan)(huan)(huan)）。

  有配管設(she)計人常咨詢筆者8字盲板(ban)與(yu)(yu)插板(ban)墊環的口徑分界(jie)(jie)問(wen)題(ti)。不(bu)同(tong)的設(she)計單位分界(jie)(jie)口徑和(he)(he)壓力(li)等級可能(neng)不(bu)相同(tong)，8字盲板(ban)和(he)(he)插板(ban)墊環在本質上沒(mei)有什么區(qu)(qu)別，區(qu)(qu)別就是當管徑比較(jiao)大、壓力(li)等級高的情況下，8字盲板(ban)的體(ti)(ti)積及(ji)重量(liang)比較(jiao)大，不(bu)方(fang)便拆卸，因(yin)此這時候通常使用(yong)(yong)(yong)插板(ban)墊環來代(dai)替。例如對于Class 150的管道(dao)，DN300以下常用(yong)(yong)(yong)8字盲板(ban)，DN350以上常用(yong)(yong)(yong)插板(ban)墊環。具體(ti)(ti)見(jian)《工業管道(dao)配管設(she)計與(yu)(yu)工程應(ying)用(yong)(yong)(yong)》、《管道(dao)器材(cai)選用(yong)(yong)(yong)與(yu)(yu)工程應(ying)用(yong)(yong)(yong)》的詳細講述。

  某DN600插(cha)板(ban)墊環：材(cai)料選(xuan)(xuan)用A516-70，厚度和等級(ji)選(xuan)(xuan)用Class150。端部選(xuan)(xuan)用RF（突面），標準選(xuan)(xuan)用ASME B16.48。