Factory Inspection



GUIDELINES FOR FACTORY INSPECTION: 

1) Marking

Each fitting shall have cast, stamped or indelibly painted on it the following appropriate marks:

  1. Manufacturer’s name, initials or identification mark,
  2. The nominal diameter,
  3. Mass of fittings and
  4. The last two digits for the year of manufacture.

Marking may be done on the outside of socket or on the barrel of the fitting.

2) Sampling (as per11606-1986)

      Scale of sampling and criteria for acceptance for dimensional requirements, Mass and straightness of pipes

Lot size

Sample size

Acceptance No.

 Up to 50

8

0

51 to 100

13

1

101 to 150

20

1

151 to 300

32

2

301 and above

50

3

3) Mechanical Tests

-Tensile Test: The results of test shall show a minimum tensile strength of 150 Mpa (N/mm2)

- Brinells Hardness Test: Brinell hardness should not exceed 230 HBS.

               If the tests of (i) &(ii) fails for the first time again two samples should be collected for further doing the same tests then also if we get negative results the lot be treated as not complying with standards.

4) Hydrostatic Test

    - For hydrostatic tests, the fittings shall be kept under pressure for 15 sec.

   - The fittings shall withstand the Pressure given below

Nominal Diameter

 Test Pressure

Fittings without branches or with branches not greater than half the Principal diameter 

MPa (Kgf/cm2)

fittings with branches greater than half the Principal diameter

MPa (Kgf/cm2)

Up to and including 300 mm

2.5 (25)

2.5 (25)

Over 300 mm and up to and including 600 mm

2.0 (20)

2.0 (20)

Over 600 mm and Up to and including 1500 mm

1.5 (15)

1.5(15)

   - They shall withstand the pressure without showing any leakage, sweating or other defect of any kind. Coating:  After Inspection and Hydro test each fitting shall be coated.

                    

Tolerances on lengths of fittings, normally manufactured, shall be as follows:

Type of Fitting

Nominal Dia

Tolerance mm

Socket fittings and flange

and spigot pieces

Up to and including 450 mm

± 20

Over 450 mm

+20

-30

Flanged fittings

All diameters

±10

Tolerances on the wall thickness and flange thickness of fittings are limited as follows:

Dimension

Tolerance, mm

Wall thickness

-(2 +0.05 e)

Flange thickness

±(3 +0.05 b)

      Where,

          e = the standard thickness of the wall in mm, and

          b = the standard thickness of the flange in mm.

Tolerances on height of raised face (c) in mm

Height of raised face (c)

Tolerance

3

+1.5

-2.0

4

+2.0

-3.0

5

+2.5

-4.0

Tolerance on the External diameter “D” in mm

Nominal Diameter

80,100,125

150,200,

250,300

350,400,450,

500,600

Tolerance

±4.5

+5.5

-2.5

+6.5

-3

Nominal Diameter

700,750,800,

900,1000

1050,1100,

1200

1500

Tolerance

+7.5

-4.0

+8.5

-4.0

+10

-5.0

-Mass:

   -  The Permissible tolerances on standard mass of fittings shall be ± 8 percent except for bends, fittings with more than one branch and non-standard fittings in which case the tolerance shall be ±12 percent   

ANNEXURE VIII: GUIDELINES FOR FACTORY INSPECTION OF HORIZONTALLY CAST IRON DOUBLE FLANGED PIPE FOR WATER, GAS AND SEWAGE (IS 7181:1996)

1) Marking

(i) Trade mark of the manufacturer, Nominal diameter, Class of pipe, Mass and the Last two digits of the year of manufacture.

(ii) Marking may be either cast, stamped or indelibly painted on the barrel.

(iii) ISI Certification.

2) Sampling (as per11606-1986)

       Scale of sampling and criteria for acceptance for dimensional requirements, Mass and straightness of pipes

Lot size

Sample size

Acceptance No.

 Up to 50

8

0

51 to 100

13

1

101 to 150

20

1

151 to 300

32

2

301 and above

50

3

3) Sizes:

Nominal Diameters (in mm) – 80,100,125,150,200,250,300,350,400,450,500,600,700 and 750.

4) Mechanical Tests:

These tests shall be carried out every 4 hours interval during manufacture of pipe.

 (i) Tensile Test: Minimum tensile strength shall be 150MPa.

(ii) Hardness Test: Brinell hardness should not exceed 230 HBS.

If the tests of (i) &(ii) fails for the first time again two samples should be collected for further doing the same tests then also if we get negative results the lot be treated as not complying with standards.

5) Hydrostatic Test:

    - Test shall be carried before surface coating.

Nominal Diameter, DN

(mm)

Test Pressure

(MPa)

Duration

(Seconds)

 Up to and including 300 mm

2.50

15

Over 300 and Up to and including 600 mm

2.0

15

Over 600 mm

1.50

15

Pipe Details:

Nominal

Diameter DN

(mm)

Pipe

DE

(mm)

e

(mm)

Wt/m

(kg)

Tolerance

±(4.5+0.0015DN)

-(1+0.05e)

+8

-5

80

98  

{93.38 - 102.62}

10 

 {8.5-10.0}

19.8 

{18.825-21.384}

100

118  

{113.35 - 122.65}

10.5  

{8.975-10.5}

25.4  

{24.13-27.432}

125

144  

{139.313 - 148.687}

11.1  

{9.545-11.1}

33.1 

 {31.445-35.748}

150

170  

{165.275 - 174.725}

11.7 

{10.115-11.7}

41.6  

{39.52-44.928}

Tolerance

----

---

±5

200

222  

{217.2 - 226.8}

12.8  

{11.16 - 12.8}

60.1  

{57.095 - 63.105}

250

274  

{269.125 - 278.875}

14.0  

{12.3 - 14.0}

81.8  

{77.71 - 85.89}

300

326  

{321.05 - 330.95}

15.2  

{13.44 - 15.2}

106.1  

{100.795 - 111.405}

350

378  

{372.975 - 383.025}

16.3  

{14.485 - 16.3}

133.5  

{126.825 - 140.175}

400

429  

{423.9 - 434.1}

17.5  

{15.625 - 17.5}

162.6  

{154.47 - 170.73}

450

480  

{474.825 - 485.175}

18.7  

{16.765 - 18.7}

197.0  

{187.15 - 206.85}

500

532  

{526.75 - 537.25}

19.8  

{17.81 - 19.8}

229.3  

{217.835 - 240.765}

600

635  

{629.6 - 640.4}

22.2  

{20.09 - 22.2}

306.5  

{291.175 - 321.825}

700

738  

{732.44 - 743.56}

24.5 

{22.275 - 24.5}

394.3  

{374.585 - 414.015}

750

790  

{784.375 - 795.625}

25.6  

{23.32 - 25.6}

443.8  

{421.61 - 465.99}

Flange Details : 

 

DN

(mm)

Flange

OD

(mm)

PCD

(mm)

Hole dia

No. of holes

Thickness

(mm)

Mass of each

(kg)

Tolerance

+3

-1

±1

+2

-0

--

±(2+0.05b)

+8

-5

80

200  {199  – 203}

160  {159 - 161}

19  {19 - 21}

4

21  {17.95 - 24.05}

3.7  {3.515 – 3.996}

100

220  {219 - 223}

180  {179 - 181}

19  {19 - 21}

8

22  {18.9 - 25.1}

4.2  {3.99 – 4.536}

125

250  {249 - 253}

210  {209 - 211}

19  {19 - 21}

8

22.5 {19.375 - 25.625}

5.3  {5.035 – 5.724}

150

285  {284 - 288}

240  {239 - 241}

23  {23 - 25}

8

23.0  {19.85 - 26.15}

6.7  {6.365 – 7.236}

Tolerance

---

-----

---

---

----

±5

200

340  {339 - 343]

295  {294 - 296}

23  {23 - 25}

8

24.5 {21.275 - 27.725}

9.3  {8.835 – 9.765}

250

395  {394 - 398}

350  {349 - 351}

23  {23 - 25}

12

26.0  {22.7 - 29.3}

12.0  {11.4 – 12.6}

Tolerance

+5

-1.5

±

1.5

---

---

---

---

300

445  {443.5 - 450}

400  {398.5 - 401.5}

23  {23 - 25}

12

27.5 {24.125 - 30.875}

14.8 {14.06 – 15.54}

Tolerance

----

---

 

+3

- 0

----

----

----

350

505 {503.5 - 510}

460 {458.5 - 461.5}

23 {23 - 26}

16

29.0 {25.55 - 32.45}

19.0 {18.05 – 19.95}

400

565 {563.5 - 570}

515 {513.5 - 516.5}

28 {28 - 31}

16

30.0 {26.5 - 33.5}

23.4 {22.23 – 24.57}

450

615 {613.5 - 620}

565 {563.5 - 566.5}

28 {28 - 31}

20

31.5 {27.925 - 35.075}

26.5 {26.175 – 27.825}

500

670 {668.5 - 675}

620 {618.5 - 621.5}

28 {28 - 31}

20

33.0 {29.35 - 36.65}

32.1 {30.495–33.705}

600

750 {778.5 - 785}

725 {723.5 - 726.5}

31 {31 - 34}

20

36.0 {32.2 - 39.8}

44.0 {41.8 – 46.2}

700

895 {893.5 - 900}

840 {838.5 - 841.5}

31 {31 - 34}

24

38.5 {34.575-42.425}

59.9{56.905– 62.895}

750

960 {958.5 - 965}

900 {898.5 - 901.5}

31 {31 - 34}

24

40.0 {36 - 44}

69.7 {66.215 – 73.185}

DN

(mm)

Single flanged Mass Chart (in kg)

 

0.6m

0.9m

1.0m

1.5m

2.0m

2.5m

3.0m

Tolerance

+ 8%, - 5%

80

15.58

{14.801 – 16.826}

21.52

{20.444 – 23.241}

23.5

{22.325 – 25.38}

33.4

{31.73 – 36.072}

43.3

{41.135 – 46.764}

53.2

{50.54 – 57.456}

63.1

{59.945 – 68.148}

100

19.44

{18.468 – 20.995}

27.06

{25.707 – 29.225}

29.6

{28.12 – 31.968}

42.3

{40.185 – 45.7}

55

{52.25 – 59.4}

67.7

{64.315 – 75.516}

80.4

{76.38 – 86.832}

125

25.16

{23.902- 27.173

35.09

{33.335 – 37.897}

38.4

{36.48 – 41.472}

54.95

{52.20 – 59.346}

71.5

{67.925 – 77.22}

88.05

{83.647 – 95.094}

104.6

{99.37 – 112.968}

150

31.66

{30.037 – 34.193}

44.14

{41.933 – 47.671}

48.3

{45.885 – 52.164}

69.1

{65.645 – 74.628}

89.9

{85.405 – 97.02}

110.7

{105.165 – 119.556}

131.5

{124.925 – 142.02}

Tolerance

± 5%

200

45.36

{43.092 – 47.628}

63.39

{60.221 – 66.559}

69.4

{65.93 – 72.87}

99.45

{94.478 – 104.422}

129.5

{123.125 – 135.975}

159.55

{151.573 – 167.527}

189.6

{180.12 – 199.08}

250

61.08

{58.026 – 64.134}

85.62

{81.339 – 89.901}

93.8

{89.11 – 98.49}

134.7

{127.965 – 141.435}

175.6

{166.82 – 184.38}

216.5

{205.675 – 227.325}

257.4

{244.53 – 270.27}

300

78.46

{74.537- 82.383}

110.29

{104.776 – 115.804}

120.9

{114.855 – 126.945}

173.95

{165.253 – 182.647}

227

{215.65 – 238.35}

280.05

{266.048 – 294.052}

333.1

{316.445 – 349.755}

350

99.1

{94.145 – 104.055}

139.15

{132.193 – 146.017}

152.5

{144.875 – 160.125}

219.25

{208.238 – 230.212}

286

{271.7 – 300.3}

352.75

{335.113 – 370.387}

419.5

{398.525 – 440.475}

400

120.96

{114.912 – 127.008}

169.74

{161.2353 – 178.227}

186

{176.7 – 195.3}

267.3

{253.935 – 280.665}

348.6

{331.17 – 366.03}

429.65

{408.168 – 451.132}

510.9

{485.355 – 536.445}

450

 

144.7

{137.465 – 151.935}

 

203.8

{193.6 – 213.99}

 

223.5

{212.325 – 234.675}

 

322

{305.9 – 338.1}

 

420.5

{399.475 – 441.525}

 

519

{493.05 – 544.95}

 

617.5

{586.625 – 648.375}

 

500

169.5

{161.02 – 77.975}

238.47

{226.547 – 250.393}

261.4

{248.33 – 274.47}

376.05

{357.248 – 394.852}

490.7

{466.165 – 515.235}

605.35

{575.083 – 635.617}

720

{684 – 756}

600

227.9

{216.505 – 239295}

319.85

{303.858 – 335.842}

350.5

{332.975 – 368.025}

503.75

{478.563 – 528.937}

657

{624.15 – 689.85}

810.25

{769.738- 850.762}

963.5

{915.325 – 1011.675}

700

296.48

{281.656 – 311.304}

414.77

{394.032 – 435.508}

454.2

{431.49 – 476.91}

651.35

{618.789 – 683.917}

848.5

{806.075 – 890.925}

1045.65

{993.368 – 1097.932}

1242.8

{1180.66 – 1304.94}

750

335.98

{319.181- 352.779}

469.12

{445.664 – 492.576}

513.5

{487.825 – 539.175}

735.4

{698.63 – 772.17}

957.3

{909.435 – 1005.165}

1179.2

{1120.24 – 1238.16}

1401.1

{1331.045 – 1471.155}

DN

(mm)

Double flanged

0.6m

0.9m

1.0m

1.5m

2.0m

2.5m

3.0m

Tolerance

+ 8%, - 5%

80

19.28

{18.316 – 20.822}

25.22

{23.959 – 27.237}

27.2

{25.84 – 29.376}

37.1

{35.245 – 40.068}

47

{44.65 – 50.76}

56.9

{54.055 – 641.452}

66.8

{63.46 – 72.144}

100

23.64

{22.458 – 25.531}

31.26

{29.697 – 33.761}

33.8

{32.11 – 36.504}

46.5

{44.175 – 50.22}

59.2

{56.24 – 63.936}

71.9

{68.305 – 77.652}

84.6

{80.37 – 91.368}

125

30.46

{28.937 – 32.897}

40.39

{38.37 – 43.621}

43.7

{41.515 – 47.196}

30.25

{28.737 – 32.67}

76.8

{72.96 – 82.92}

93.35

{88.682 – 100.818

109.9

{104.405 – 118.692}

150

38.36

{36.442 – 41.428}

50.84

{48.298 – 54.907}

55

{52.25- 59.4}

75.8

{72.01 – 81.864}

96.6

{91.77 – 104.328}

117.4

{111.53 – 126.792}

138.2

{131.29 – 149.256}

Tolerance

± 5%

200

54.66

{51.927 – 97.393}

72.69

{69.056 – 76.324}

78.7

{47.765 – 82.635}

108.75

{103.313 – 114.187}

138.8

{131.86 – 145.74}

168.85

{160.408 – 177.292}

198.9

{188.955 -208.845}

250

73.08

{69.426 – 76.734 }

97.62

{92.739 – 102.501}

105.8

{100.51- 111.09}

146.7

{139.365 – 154.035}

187.6

{178.22 – 196.98}

228.5

{217.075 – 239.925}

269.4

{255.93 – 282.87}

300

93.26

{88.597 – 97.923}

125.08

{118.826 – 131.334}

135.7

{128.915 – 142.485}

188.75

{179.313 – 198.187}

241.8

{229.71 – 253.89}

294.85

{280.104 -309.592}

347.9

{330.505 – 365.295}

350

118.1

{112.195 – 124.005}

158.15

{150.243 – 166.057}

171.5

{162.925 – 180.075}

238.25

{226.338 – 250.162}

305

{289.75 – 320.25}

371.75

{353.163 – 310.337}

438.5

{416.575 – 460.425}

400

144.36

{137.085 – 151.515}

193.14

{183.483 – 202.797}

209.4

{198.93- 219.87}

290.7

{276.165 – 305.235}

372

{353.4 – 390.4}

453.05

{431.298 – 474.802}

534.3

{507.585 – 561.015}

450

171.2

{162.64 – 179.76}

230.2

{218.69 – 241.71}

250

{237.5 – 262.5}

348.5

{331.075 – 365.925}

447

{424.65 – 469.35}

545.5

{518.225 – 572.775}

644

{611.8 – 676.2}

500

201.6

{191.52 – 211.68}

270.57

{257.042 – 284.098}

293.5

{278.825 – 308.175}

408.15

{387.743 – 428.557}

522.8

{496066 – 548.94}

637.45

{605.58- 669.32}

752.1

{714.495 – 789.705}

600

271.8

{258.21 – 285.39}

363.85

{345.68 – 382.042}

394.5

{374.775 – 414.225}

547.75

{520.363 – 575.137}

701

{665.95 – 736.05}

854.25

{811.538 – 896.962}

1007.5

{957.125 – 1057.875}

700

356.38

{338.561 – 374.199}

474.67

{450.94 – 498.4
}

514.1

{488.395 – 539.805}

711.25

{675.688 – 746.812}

908.4

{862.98 – 953.82}

1105.55

{1050.273 – 1160.827}

1302.7

{1237.565 – 1367.835}

750

405.68

{385.396 – 425.964}

538.82

{511.879 – 565.761}

583.2

{554.04 – 612.36}

805.1

{764.845 – 845.335}

1027

{975.65 – 1078.35}

1248.9

{1186.455 – 1311.345}

1470.8

{1397.16 – 1544.34}

IS : 7181- 1986

Flange thickness  b = 19 +0.028 DN

Barrel wall thickness e  = (14/12)*(7+0.02 DN)

Tolerances:-

Barrel External Dia (DE) = ± (4.5 + 0.0015 DN)

Flange Thickness  =   ±(2+0.05b)

Barrel wall thickness = - (1+0.05e)

Length  =  ± 10 mm

Mass : Up to 150 mm -    +8%,  - 5%

200mm and above-   ±5%

Outside Dia of Flange (D)  : upto 250 mm -  +3.0,  -1.0 mm

Above 250 mm : +5 ,  -1.50 mm

Pitch Circle Dia (C): up to 250 mm -     ±1.0 mm

Mechanical Tests:

(i) Tensile Test: Mi

Above 250 mm-     ±1.5 mm

Bolt Hole dia (d): Up to 300 mm-   +2.0 , - 0 mm

Above 300 mm -  +3.0 , -0 mmnimum tensile strength shall be 150MPa.

 (ii) Hardness Test: Brinell hardness should not exceed 230 HBS.

Hydrostatic Test:

Up to and including 300 mm   -  2.50 MPa for 15 sec.

Over 300 and up to and including 600 mm -2.0MPa for 15 sec.

Over 600 mm   -  1.50 MPa  for 15 sec        

* * * *