渐缩管
Retraction tube
渐缩管也属于异径管类产品(也称异径短节)，目的就是变径安装两端管道。同异径管一样也分偏心与同心两种，渐缩管一般采用标准为MSS SP-95 BS3799。
The shrinkage tube also belongs to the product of the different diameter tube (also known as the different diameter and short section), the purpose is to change the diameter and install the two ends of the pipe. There are two kinds of eccentricity and concentric, and the standard is MSS SP-95 BS3799.
渐缩管与异径管区别
The difference between the tapered tube and the different diameter tube
1
One
口径范围不同
Different caliber range
异径管的口径范围比较广，目前标准中从DN15-DN3400(1/2"~136")
The diameter of the tube has a wide range, and the current standard is from DN15-DN3400 (1/2 "~136").
而渐缩管的规格范围则为:DN6-DN300(1/4"-12") 常用基本为最大DN100
The specification of the shrinking tube is that DN6-DN300 (1/4 "-12") is commonly used as the maximum DN100
2
Two
原材料区别
Raw material difference
异径管选用的是无缝钢管或钢板，无缝产品是钢管，有缝产品是钢板。
The reducer is a seamless steel tube or seamless steel plate, steel pipe products, the product is seamed steel plate.
渐缩管选用的是圆钢或钢坯。
The tapered tube is made of round steel or billet.
3
Three
生产工艺区别
Production process difference
异径管生产工艺为:无缝产品采用热压或冷压(冷压需做热处理) 有缝产品采用的是热卷制。
The production process for different diameter pipe: seamless products the use of hot or cold pressing (cold pressed to do heat treatment) with product is used in hot rolling.
渐缩管生产工艺为锻造工艺。
The production process of the gradually shrinking tube is the forging process.
4
Four
端口型式区别
Port type distinction
异径管基本全部为坡口端面，很少有平口(虽然标准中允许不锈钢或碳钢产品低于多少厚度可以采用平口端面)
The tube is basically the end face of the groove, and there is little flat. (although the standard allows the stainless steel or carbon steel products to be lower than the thickness can be used at the flat end face).
渐缩管的端口型式相比就比较多了，两端端口可以一致也可以不一致，这个要根据现场或设计的要求，端口类型有:坡口 平口 螺纹三种(后面表中有具体介绍)。
The port type of the shrink tube is much more. The two ports can be consistent or inconsistent. According to the requirements of the scene or design, the port type has three kinds: the flat port thread of the groove, and the detailed description of the following table.
渐缩管端口尺寸介绍
Introduction of the size of the tapered pipe port
说明：
Explain：
1、选用时，应予注明，对锥管螺纹还应注明NPT或R。
1, when selected, it should be noted that the taper pipe thread should also be marked NPT or R.
2、异型短节大端及小端型工分别有平端、坡口端、锥管外螺纹端三种：大、小端的各种组合共计有九种配合可能，如下表示：
2, special short end and small end type respectively, flat end beveled end cone tube external thread three: various combinations of large and small end of a total of nine kinds of complexes may, as described in the following:
型式Type
Type Type
大  端Large End
The big Large End
小端Small End
Small end Small End
代号Code
Code name Code
A
A
平
flat
平
flat
BEP
BEP
B
B
Plain
Plain
坡口
groove
LEP/SEB
LEP/SEB
C
C
螺纹
Thread
LEP/SET
LEP/SET
D
D
坡 口
Bevel
平
flat
LEB/SEP
LEB/SEP
E
E
Bevel
Bevel
坡口
groove
BEB
BEB
F
F
螺纹
Thread
LEB/SET
LEB/SET
G
G
螺 纹
Thread
平
flat
LET/SEP
LET/SEP
H
H
Thread
Thread
坡口
groove
LET/SEB
LET/SEB
I
I
螺纹
Thread
BET
BET
3、异径短节壁厚一般为Sch80(3000LB)、Sch160(6000LB)，平端、坡口端或管螺纹端。
3, the short wall thickness of the different diameter is generally Sch80 (3000LB), Sch160 (6000LB), flat end, slope end or pipe thread end.
4、本系列产品符合MSS SP95和BS3799要求。
4. This series of products meet the requirements of MSS SP95 and BS3799.