Stainless Steel Reducing Buttweld Pipe Fittings

Reducing Buttweld Pipe Fittings connect Pipe of different sizes in piping systems. They are installed via welding and contain one or more ports that are smaller in diametre than the main line, enabling splitting or merging of fluid or gas flow.

  • Stirlings stocks a range of Seamless and Welded Reducing Buttweld Pipe Fittings, including Concentric Reducer, Eccentric Reducer and Reducing Tee Fittings. These are in Austenitic 304/L, 316/L, Duplex 2205 and Super Duplex 2507.  

  • Grade 304/L and Grade 316/L Buttweld Pipe Fittings are manufactured to ASTM A403 and ASME B16.9.  

  • Grade 2205 and 2507 Buttweld Pipe Fittings are manufactured to ASTM A815.  

  • Reducing Buttweld Pipe Fittings are finished pickled.  

  • Stirlings stocks Schedule 10S, 40S, STD, 80S and XS Welded and Seamless Reducing Buttweld Pipe Fittings in sizes from ¾ x ½ inch (20 x 15mm) to 24 x 20 inches (600mm x 500mm). Everything currently in stock is specified in the tables below. 

● Stocked Item ○ Market Available

Anything not currently in stock/Market Available can be obtained via indent. 

Welded Buttweld Concentric Reducer 

 
ReSize - Nominal Bore Concentric Reducer
Inch (NPS)
mm (DN)
304L 304L 316L 316L 2205 2205
    Sch 10S Sch 40S Sch 10S Sch 40S Sch 10S Sch 40S
    FPRC3041 FPRC3044 FPRC3161 FPRC3164 FPRC22051 FPRC22054
¾ x ½ 20 x 15 ● 
1 x ½ 25 x 15
1 x ¾ 25 x 20
1¼ x ¾ 32 x 20
1¼ x 1 32 x 25
1½ x ¾ 40 x 20 ○  ● 
1½ x 1 40 x 25
1½ x 1¼ 40 x 32
2 x ¾ 50 x 20
2 x 1 50 x 25
2 x 1¼ 50 x 32 ○  ●  ● 
2 x 1½ 50 x 40
2½ x 1¼ 65 x 32
2½ x 1½ 65 x 40
2½ x 2 65 x 50
3 x 1 80 x 25
3 x 1¼ 80 x 32
3 x 1½ 80 x 40
3 x 2 80 x 50
3 x 2½ 80 x 65
4 x  1½ 100 x 40
4 x 2 100 x 50
4 x 2½ 100 x 65
4 x 3 100 x 80
5 x 2½ 125 x 65
5 x 3 125 x 80
5 x 4 125 x 100
6 x 2½ 150 x 65
6 x 3 150 x 80
6 x 4 150 x 100
6 x 5 150 x 125
8 x 4 200 x 100
8 x 5 200 x 125
8 x 6 200 x 150
10 x 4 250 x 100
10 x 5 250 x 125
10 x 6 250 x 150
10 x 8 250 x 200
12 x 6 300 x 150 ○  ○ 
12 x 8 300 x 200
12 x 10 300 x 250 ○  ○  ● 
      STD   STD    
14 x 8 350 x 200 ○  ○ 
14 x 10 350 x 250 ○  ○ 
14 x 12 350 x 300 ○  ○ 
16 x 8 400 x 200
16 x 10 400 x 250 ○  ○ 
16 x 12 400 x 300 ○  ○ 
16 x 14 400 x 350 ○  ○ 
18 x 12 450 x 300 ○  ○ 
18 x 14 450 x 350 ○  ○ 
18 x 16 450 x 400 ○  ○ 
20 x 12 500 x 300 ○  ○ 
20 x 14 500 x 350
20 x 16 500 x 400 ○  ○ 
20 x 18 500 x 450 ○  ○ 
24 x 12 600 x 300 ○  ○ 
24 x 14 600 x 350
24 x 16 600 x 400 ○  ○ 
24 x 18 600 x 450 ○  ○ 
24 x 20 600 x 500 ○  ○ 
30 x 24 750 x 600            

 

 Seamless Buttweld Concentric Reducer 

 
ReSize - Nominal Bore Concentric Reducer
Inch (NPS)
mm (DN)
304L 304L 304L 316L 316L 316L 2205 2205 2205 2507
    Sch 10S Sch 40S Sch 80S Sch 10S Sch 40S Sch 80S Sch 10S Sch 40S Sch 80S Sch 40S
    SMLS SMLS SMLS SMLS SMLS SMLS SMLS SMLS SMLS SMLS
                       
¾ x ½ 20 x 15
1 x ½ 25 x 15
1 x ¾ 25 x 20
1¼ x ¾ 32 x 20
1¼ x 1 32 x 25
1½ x ¾ 40 x 20
1½ x 1 40 x 25
1½ x 1¼ 40 x 32
2 x ¾ 50 x 20
2 x 1 50 x 25
2 x 1¼ 50 x 32
2 x 1½ 50 x 40
2½ x 1½ 65 x 40
2½ x 2 65 x 50
3 x 1½ 80 x 40
3 x 2○ 80 x 50
3 x 2½ 80 x 65
4 x 2 100 x 50
4 x 2½ 100 x 65
4 x 3 100 x 80
5 x 3 125 x 80
5 x 4 125 x 100 ○ 
6 x 3 150 x 80
6 x 4 150 x 100
6 x 5 150 x 125
8 x 4 200 x 100 ○ 
8 x 5 200 x 125
8 x 6 200 x 150
10 x 4 250 x 100 ○ 
10 x 6 250 x 150 ○ 
10 x 8 250 x 200
12 x 6 300 x 150 ○ 
12 x 8 300 x 200 ○ 
12 x 10 300 x 250 ○ 
            STD XS        
14 x 8 350 x 200 ○ 
14 x 10 350 x 250 ○ 
14 x 12 350 x 300 ○ 
16 x 8 400 x 200
16 x 10 400 x 250 ○ 
16 x 12 400 x 300 ○ 
16 x 14 400 x 350 ○ 
18 x 12 450 x 300 ○ 
18 x 14 450 x 350 ○ 
18 x 16 450 x 400 ○ 
20 x 12 500 x 300 ○ 
20 x 14 500 x 350
20 x 16 500 x 400 ○ 
20 x 18 500 x 450 ○ 
24 x 12 600 x 300 ○ 
24 x 14 600 x 350
24 x 16 600 x 400 ○ 
24 x 18 600 x 450 ○ 
24 x 20 600 x 500 ○ 

 

 

 Welded Buttweld Eccentric Reducer  

 
ReSize - Nominal Bore Eccentric Reducer
Inch (NPS) mm (DN) 304L 304L 316L 316L 316L
    Sch 10S Sch 40S Sch 10S Sch 40S Sch 80S
             
¾ x ½ 20 x 15 ●  ● 
1 x ½ 25 x 15
1 x ¾ 25 x 20
1¼ x 1 32 x 25 ●  ● 
1½ x ¾ 40 x 20
1½ x 1 40 x 25
1½ x 1¼ 40 x 32 ●  ● 
2 x ¾ 50 x 20
2 x 1 50 x 25
2 x 1¼ 50 x 32
2 x 1½ 50 x 40
2½ x 1½ 65 x 40 ●  ● 
2½ x 2 65 x 50
3 x 1½ 80 x 40
3 x 2 80 x 50
3 x 2½ 80 x 65 ● 
4 x 1½ 100 x 40
4 x 2 100 x 50
4 x 2½ 100 x 65
4 x 3 100 x 80
5 x 3 125 x 80
5 x 4 125 x 100 ● 
6 x 2 150 x 50
6 x 3 150 x 80
6 x 4 150 x 100
6 x 5 150 x 125 ●  ● 
8 x 3 200 x 80
8 x 4 200 x 100 ● 
8 x 5 200 x 125
8 x 6 200 x 150
10 x 4 250 x 100 ○  ○  ○  ○ 
10 x 5 250 x 125
10 x 6 250 x 150
10 x 8 250 x 200 ●  ● 
12 x 6 300 x 150
12 x 8 300 x 200
12 x 10 300 x 250 ● 
      STD   STD  
14 x 8 350 x 200
14 x 10 350 x 250
14 x 12 350 x 300
16 x 6 400 x 200
16 x 10 400 x 250
16 x 12 400 x 300
16 x 14 400 x 350
18 x 10 450 x 250
18 x 12 450 x 300
18 x 14 450 x 350
18 x 16 450 x 400 ○  ○ 
20 x 12 500 x 300
20 x 16 500 x 400 ○  ○  ○ 
20 x 18 500 x 450
24 x 12 600 x 300
24 x 16 600 x 400 ○  ○  ○ 
24 x 18 600 x 450
24 x 20 600 x 500

 

 Welded Buttweld Reducing Tee  

 
ReSize - Nominal Bore Reducing Tee
Inch (NPS) mm (DN) 304L 316L 316L
    Sch 10S Sch 10S Sch 40S
         
¾ x ½ 20 x 15 ●  ○ 
1 x ½ 25 x 15
1 x ¾ 25 x 20
1¼ x 1 32 x 25 ●  ○ 
1½ x ¾ 40 x 20
1½ x 1 40 x 25
1½ x 1¼ 40 x 32 ●  ○ 
2 x ¾ 50 x 20
2 x 1 50 x 25
2 x 1¼ 50 x 32 ●  ○ 
2 x 1½ 50 x 40
2½ x 1½ 65 x 40 ○  ○ 
2½ x 2 65 x 50
3 x 1½ 80 x 40
3 x 2 80 x 50
3 x 2½ 80 x 65 ●  ○ 
4 x 1½ 100 x 40
4 x 2 100 x 50
4 x 2½ 100 x 65
4 x 3 100 x 80
5 x 3 125 x 80
5 x 4 125 x 100 ●  ○ 
6 x 2 150 x 50
6 x 3 150 x 80
6 x 4 150 x 100
6 x 5 150 x 125 ●  ○ 
8 x 3 200 x 80
8 x 4 200 x 100
8 x 5 200 x 125
8 x 6 200 x 150
10 x 4 250 x 100 ●  ○ 
10 x 5 250 x 125
10 x 6 250 x 150
10 x 8 250 x 200 ● 
12 x 6 300 x 150
12 x 8 300 x 200
12 x 10 300 x 250
        STD
14 x 8 350 x 200
14 x 10 350 x 250
14 x 12 350 x 300
16 x 6 400 x 200
16 x 10 400 x 250
16 x 12 400 x 300
16 x 14 400 x 350
18 x 10 450 x 250
18 x 12 450 x 300
18 x 14 450 x 350
18 x 16 450 x 400 ●  ○ 
20 x 12 500 x 300
20 x 16 500 x 400 ○ 
20 x 18 500 x 450
24 x 12 600 x 300
24 x 16 600 x 400 ●  ○ 
24 x 18 600 x 450
24 x 20 600 x 500

 

Seamless Buttweld Eccentric Reducer

 
ReSize - Nominal Bore Eccentric Reducer
Inch (NPS) mm (DN) 304L 304L 316L 316L 2205 2205
    Sch 10S Sch 40S Sch 10S Sch 40S Sch 10S Sch 40S
    SMLS SMLS SMLS SMLS SMLS SMLS
               
¾ x ½ 20 x 15
1 x ½ 25 x 15
1 x ¾ 25 x 20
1¼ x ¾ 32 x 20
1¼ x 1 32 x 25
1½ x ¾ 40 x 20
1½ x 1 40 x 25
1½ x 1¼ 40 x 32
2 x 1 50 x 25
2 x 1¼ 50 x 32
2 x 1½ 50 x 40
2½ x 1½ 65 x 40
2½ x 2 65 x 50
3 x 1½ 80 x 40
3 x 2 80 x 50
3 x 2½ 80 x 65
4 x 2 100 x 50
4 x 2½ 100 x 65
4 x 3 100 x 80
5 x 3 125 x 80
5 x 4 125 x 100
6 x 3 150 x 80
6 x 4 150 x 100
6 x 5 150 x 125 ●  ● 
8 x 4 200 x 100
8 x 5 200 x 125
8 x 6 200 x 150
10 x 4 250 x 100 ○  ○ 
10 x 6 250 x 150
10 x 8 250 x 200 ○  ○ 
12 x 6 300 x 150
12 x 8 300 x 200
12 x 10 300 x 250 ○  ○ 
      STD   STD    
18 x 16 450 x 400 ○  ○  ○  ○ 
20 x 16 500 x 400 ○  ○  ○  ○ 
24 x 16 600 x 400 ○  ○  ○  ○ 

 

Seamless Buttweld Reducing Tee

 
ReSize - Nominal Bore Reducing Tee
Inch (NPS) mm (DN) 304L 304L 316L 316L 2205
    Sch 10S Sch 40S Sch 10S Sch 40S Sch 40S
    SMLS SMLS SMLS SMLS SMLS
             
¾ x ½ 20 x 15
1 x ½ 25 x 15
1 x ¾ 25 x 20
1¼ x ¾ 32 x 20
1¼ x 1 32 x 25
1½ x ¾ 40 x 20
1½ x 1 40 x 25
1½ x 1¼ 40 x 32
2 x 1 50 x 25
2 x 1¼ 50 x 32
2 x 1½ 50 x 40
2½ x 1½ 65 x 40
2½ x 2 65 x 50
3 x 1½ 80 x 40
3 x 2 80 x 50
3 x 2½ 80 x 65
4 x 2 100 x 50
4 x 2½ 100 x 65
4 x 3 100 x 80
5 x 3 125 x 80
5 x 4 125 x 100
6 x 3 150 x 80
6 x 4 150 x 100
6 x 5 150 x 125
8 x 4 200 x 100
8 x 5 200 x 125
8 x 6 200 x 150
10 x 4 250 x 100
10 x 6 250 x 150
10 x 8 250 x 200
12 x 6 300 x 150
12 x 8 300 x 200
12 x 10 300 x 250
      STD      
18 x 16 450 x 400 ○  ○ 
20 x 16 500 x 400 ○  ○ 
24 x 16 600 x 400 ○  ○ 

 

 

Technical Data

 

Imperial Metric Conc. & Ecc. Reducers
    O.D. 1 O.D. 2 H Wgt 10S Wgt 40S Wgt 80S Wgt 160S
¾ x ½ 20 x 15 26.7 21.3 39.3 0.05 0.06 0.08 0.11
1 x ½ 25 x 15 33.4 21.3 50.8 0.09 0.11 0.14 0.18
1 x ¾ 25 x 20 33.4 26.7 50.8 0.12 0.14 0.18 0.23
1¼ x ¾ 32 x 20 42.2 26.7 50.8 0.11 0.14 0.18 0.23
1¼ x 1 32 x 25 42.2 33.4 50.8 0.13 0.16 0.21 0.28
1½ x ¾ 40 x 20 48.3 26.7 63.5 0.15 0.2 0.27 0.36
1½ x 1 40 x 25 48.3 33.4 63.5 0.17 0.22 0.29 0.38
1½ x 1¼ 40 x 32 48.3 42.2 63.5 0.18 0.24 0.32 0.43
2 x ¾ 50 x 20 60.3 26.7 76.2 0.22 0.3 0.41 0.56
2 x 1 50 x 25 60.3 33.4 76.2 0.23 0.32 0.44 0.6
2 x 1¼ 50 x 32 60.3 42.2 76.2 0.25 0.35 0.48 0.66
2 x 1½ 50 x 40 60.3 48.3 76.2 0.27 0.37 0.51 0.7
2½ x 1¼ 65 x 32 73 42.2 88.9 0.38 0.63 0.83 1.09
2½ x 1½ 65 x 40 73 48.3 88.9 0.4 0.66 0.87 1.15
2½ x 2 65 x 50 73 60.3 88.9 0.44 0.72 0.95 1.25
3 x 1 80 x 25 88.9 33.4 88.9 0.4 0.7 0.94 1.28
3 x 1¼ 80 x 32 88.9 42.2 88.9 0.43 0.76 1.03 1.4
3 x 1½ 80 x 40 88.9 48.3 88.9 0.44 0.78 1.05 1.41
3 x 2 80 x 50 88.9 60.3 88.9 0.48 0.85 1.15 1.56
3 x 2½ 80 x 65 88.9 73 88.9 0.53 0.93 1.26 1.71
4 x 1½ 100 x 40 114.3 48.3 101.6 0.61 1.18 1.64 2.28
4 x 2 100 x 50 114.3 60.3 101.6 0.66 1.27 1.77 2.47
4 x 2½ 100 x 65 114.3 73 101.6 0.71 1.37 1.9 2.64
4 x 3 100 x 80 114.3 88.9 101.6 0.75 1.45 2.02 2.81
5 x 2½ 125 x 65 141.3 73 127 1.14 2.16 3.07 4.36
5 x 3 125 x 80 141.3 88.9 127 1.2 2.27 3.22 4.57
5 x 4 125 x 100 141.3 114.3 127 1.33 2.5 3.55 5.04
6 x 2½ 150 x 65 168.3 73 139.7 1.42 2.89 5.66 11.08
6 x 3 150 x 80 168.3 88.9 139.7 1.49 3.04 5.94 11.61
6 x 4 150 x 100 168.3 114.3 139.7 1.62 3.3 4.98 7.52
8 x 4 200 x 100 219.1 114.3 152.4 2.4 5.1 7.75 11.78
8 x 5 200 x 125 219.1 141.3 152.4 2.54 5.4 8.21 12.48
8 x 6 200 x 150 219.1 168.3 152.4 2.68 5.71 8.68 13.19
10 x 4 250 x 100 273.1 114.3 177.8 4.73 10.52 12.56 15
10 x 5 250 x 125 273.1 141.3 177.8 3.87 8.42 11.37 15.35
10 x 6 250 x 150 273.1 168.3 177.8 4 8.78 14 22.32
10 x 8 250 x 200 273.1 219.1 177.8 4.4 9.58 15.2 24.12

 

Imperial Metric Reducing Tee
    C M Wgt 10S Wgt 40S Wgt 80S Wgt 160S
¾ x ½ 20 x 15 29 29 0.09 0.12 0.16 0.21
1 x ½ 25 x 15 38 38 0.18 0.22 0.29 0.38
1 x ¾ 25 x 20 38 38 0.19 0.23 0.3 0.39
1¼ x ¾ 32 x 20 49 48 0.3 0.37 0.48 0.62
1¼ x 1 32 x 25 49 49 0.31 0.39 0.51 0.67
1½ x ¾ 40 x 20 57 57 0.4 0.52 0.7 0.94
1½ x 1 40 x 25 57 57 0.42 0.55 0.74 1
1½ x 1¼ 40 x 32 57 57 0.44 0.57 0.76 1.01
2 x ¾ 50 x 20 64 44 0.5 0.7 0.96 1.32
2 x 1 50 x 25 64 51 0.53 0.74 1.02 1.41
2 x 1¼ 50 x 32 64 57 0.58 0.8 1.1 1.51
2 x 1½ 50 x 40 64 60 0.6 0.83 1.15 1.59
2½ x 1¼ 65 x 32 76 64 0.84 1.38 1.82 2.4
2½ x 1½ 65 x 40 76 67 0.91 1.49 1.97 2.6
2½ x 2 65 x 50 76 70 0.93 1.53 2.02 2.67
3 x 1 80 x 25 86 67 1.1 1.95 2.65 3.6
3 x 1¼ 80 x 32 86 70 1.14 2 2.7 3.65
3 x 1½ 80 x 40 86 73 1.17 2.05 2.77 3.74
3 x 2 80 x 50 86 76 1.23 2.16 2.92 3.95
3 x 2½ 80 x 65 86 83 1.31 2.29 3.09 4.17
4 x 1½ 100 x 40 105 86 1.77 3.41 4.74 6.59
4 x 2 100 x 50 105 89 1.83 3.52 4.89 6.79
4 x 2½ 100 x 65 105 95 1.92 3.7 5.14 7.14
4 x 3 100 x 80 105 98 2.5 4.8 6.67 9.27
5 x 2½ 125 x 65 124 108 3.02 5.71 8.1 11.49
5 x 3 125 x 80 124 111 3.1 5.85 8.31 11.8
5 x 4 125 x 100 124 117 3.25 6.14 8.72 12.38
6 x 2½ 150 x 65 143 121 4.05 8.25 12.5 18.9
6 x 3 150 x 80 143 124 4.17 8.52 12.9 19.53
6 x 4 150 x 100 143 130 4.32 8.81 13.3 20.08
8 x 4 200 x 100 178 156 7.47 15.9 24.2 36.83
8 x 5 200 x 125 178 162 7.66 16.3 24.8 37.73
8 x 6 200 x 150 178 168 7.9 16.8 25.5 38.71
10 x 4 250 x 100 216 184 7.47 15.9 24.2 36.83
10 x 5 250 x 125 216 191 12.5 27.1 36.6 49.43
10 x 6 250 x 150 216 194 12.7 27.6 43.9 69.83
10 x 8 250 x 200 216 203 13.3 28.9 46 73.22