閥門選用步驟選用閥門一般應采用以下步驟
選用閥門一般應采用以下步驟。
①明確閥門在裝置或工藝管道中的用途，確定閥門的工作狀況，例如操作介質、操作
壓力、操作溫度。
②根據(jù)閥門的用途確定閥門的種類，如開閉路閥門、調節(jié)類閥門、安全類閥門、其他
類閥門等。
③確定閥門的形式.根據(jù)用途及操作工況要求，確定閥門類型為;閘閥、截止閥、球
閥、蝶閥、安全閥、疏水閥、旋塞閥等.
④確定閥門的公稱參數(shù)。閥門的公稱壓力、公稱直徑的確定應與安裝的工藝管道相匹
配。一般情況下，’工藝管道在設計時，應用的標準體系（是“大外徑系列”還是“小外徑系
列，’）是決定壓力管路其他元件應用標準的基礎.例如，如果選用“小外徑系列”的管子應
用標準，它只能與JB法蘭或HGJ法蘭匹配，而閥門應是JB系列閥門，否則，無法匹配使
用.同理，若使用“大外徑系列”管子，它與ANSI, ISO及GB標準相匹配使用，不銹鋼人孔，并能與
API閥門匹配使用。閥門一般是安裝在工藝管道中，因此其操作工況應隨工藝管道的設計選
擇相一致，管道的壓力等級確定后，閥門的公稱壓力自然就定下來了.管道采用的標準體系
及管道壓力等級確定后，所采用閥門的公稱壓力、公稱直徑、不銹鋼離心泵，閥門標準就可確定下來。
⑤確定閥門材質。根據(jù)工藝管道的介質、工作壓力、工作溫度確定所選用閥門的殼體
及內(nèi)部零件的材料:鑄鐵、鑄鋼、不銹鋼隔膜閥，鍛造閥門、合金鋼、不銹鋼等材料.
⑥確定閥門與管道的連接方式:由操作工況條件確定閥門端面與管道的連接采用法蘭、
螺紋或是焊接連接等方式。
⑦利用閥門樣本資料，選擇合適的閥門產(chǎn)品。
⑧閥門型號確定后，可查出所選閥門的幾何參數(shù):結構長度、法蘭連接形式及尺寸
（或其他方式連接）、啟閉時閥門高度、連接的螺栓孔尺寸及數(shù)量、整個閥門的外形尺寸及重
量等，為閥門現(xiàn)場安裝打下基礎。
1.1. 1
閥門選型舉例
原油曦區(qū)閥門的選型
原油罐區(qū)閥門工況條件主要有:①操作壓力較低，一般0- 1.OMPa;②管徑比較大，
一般DN<1000mm;③操作溫度鎮(zhèn)2000;④原油介質不純凈（帶懸浮固體穎粒等）。從現(xiàn)
有主流閥型分析，截止閥由于啟閉力矩較大，不銹鋼人孔，一般其通徑DN<250mm;球閥結構復雜，體
積龐大，一般對于DN）500mm的管道，選用球閥是不經(jīng)濟的。因此，目前的罐區(qū)閥門大
zui選用閘閥和蝶閥。這兩種閥型的主要技術特性對比如下。
①閘閥主要有平板閘閥和楔式閘閥兩種，其主要特點有:a.流體阻力小，b.雙向性能
好，介質流向不受限制;c.體積龐大，所需安裝空間較大;d.啟閉行程大，全行程動作時
間長;e.在開啟狀態(tài)下，閘閥導向槽易沉積雜質，導致閘板在關閉時不能嚴密切斷;f.在
啟閉過程中，密封面間有機械摩擦，密封面易損壞;9.閥門壽命短.由上述分析可知，閘
閥用于原油罐區(qū)，由于原油介質帶有懸浮固體順粒，會引進閥門關閉不嚴，密封面操作而泄.
 Optional consistent, determined the pressure rating of the pipe, the valve nominal pressure naturally settle down pipe with the standard system
And pipeline pressure rating is determined by the valve nominal pressure, nominal diameter, stainless steel centrifugal pump, valve standard can be finalized.
（5） determine the valve material. According to media process piping, working pressure, working temperature to determine the selection of valve housing
And internal parts of the material: cast iron, cast steel, stainless steel diaphragm valves, forged valves, alloy steel, stainless steel and other materials.
⑥ determine the valve and pipe connections: to be determined by the operating conditions of the valve face and pipeline connection with flange
Threaded or welded connections.
⑦ the use of the the valve sample data, select the appropriate valve products.
⑧ valve models to determine the geometric parameters: the length of the structure of the selected valve flange connection form and dimensions, can be identified
（Or otherwise connected）, open and close the valve height, the connection bolt hole size and quantity, the entire valve Dimensions and weight
The amount for the valve-site installation lay the foundation.
1.1.
Examples of valve selection
Crude oil Xi District valve selection
Crude oil tank valve working conditions: ① operating pressure is low, generally - 1.OMPa; ② diameter relatively large
Generally the DN <1000mm; （3） operating temperature of the town of 2000; ④ crude medium is not pure （with the suspended solid Ying tablets）. From now
Mainstream valve type analysis shutoff valve due to a larger opening and closing moments, stainless steel manhole, general diameter DN <250mm; complex structure ball valve body
Plot large general DN） 500mm pipe, optional ball valve is not economical. Therefore, the tank farm valve
The best selection of gate valves and butterfly valves. Both the main technical characteristics of the type of valve comparison below.
① gate valve mainly flat gate and two wedge gate valve, its main features are: a fluid resistance, b. Bidirectional performance
Good medium flow unrestricted; c. Bulky installation space required; d. Headstock stroke, when the action of the whole trip
Length between; e in the open state, gate guide groove easily deposited impurities, resulting not closely cut off by the shutter when closed; F
Opening and closing process, the sealing surface mechanical friction, easy to damage the sealing surface; 9. Valve short life. Seen from the above analysis, the gate
Valve for crude oil tank, the crude media with suspended solids cis tablets, will be introduced to the valve closed lax the sealing surface operations and vent。