Jindal Pipe Size Chart
Nominal bore to inch and outside diameter for GI and MS pipe, to IS:1239 and IS:3589 — plus the part most buyers miss: why the size number is not the pipe's measured diameter.
A Jindal pipe size chart maps nominal bore (NB) to the inch designation and outside diameter (OD). To IS:1239, 15MM is ½ inch at 21.3mm OD, 50MM is 2 inch at 60.3mm OD, and 150MM is 6 inch at 165.1mm OD. Nominal bore is a size name, not the pipe's measured diameter.
These outside diameters are the IS:1239 and IS:3589 standard values, the same for Jindal Star and Jindal Hissar, cross-checked against stock at the Delhi warehouse of Vijay Sales Corporation and supplied pan-India.
Jindal Pipe Size Chart — IS:1239 (15MM to 150MM)
Nominal bore in millimetres and inches, with the outside diameter in millimetres. Outside diameter is one value per size; the wall thickness changes with class, not the OD.
| Nominal bore (mm) | Nominal bore (inch) | Outside diameter OD (mm) |
|---|---|---|
| 15MM | ½″ | 21.3 |
| 20MM | ¾″ | 26.9 |
| 25MM | 1″ | 33.7 |
| 32MM | 1¼″ | 42.4 |
| 40MM | 1½″ | 48.3 |
| 50MM | 2″ | 60.3 |
| 65MM | 2½″ | 76.1 |
| 80MM | 3″ | 88.9 |
| 100MM | 4″ | 114.3 |
| 125MM | 5″ | 139.7 |
| 150MM | 6″ | 165.1 |
Outside diameter is the standard nominal OD to IS:1239; the manufactured tolerance band is small (for example, 15MM measures about 21.0 to 21.8mm across classes). The same OD carries Light, Medium and Heavy classes — the class is set by wall thickness, which is on the class A, B, C guide, and drives the weight on the weight chart.
Large-Size Chart — IS:3589 (150MM to 300MM)
Where IS:1239 ends, IS:3589 begins. Large-diameter pipe is designated by nominal bore and outside diameter.
| Nominal bore (mm) | Outside diameter OD (mm) |
|---|---|
| 150MM | 168.3 |
| 175MM | 193.7 |
| 200MM | 219.1 |
| 250MM | 273.0 |
| 300MM | 323.9 |
150MM appears in both charts because it sits on the boundary: to IS:1239 its outside diameter is 165.1mm, and to IS:3589 it is 168.3mm. Confirm which standard a 150MM line is specified to.
Beyond 300MM, sizes are supplied to order — up to 400MM in black and 300MM in GI for Jindal Hissar, and up to 600MM for Jindal Star. WhatsApp the size for its outside diameter →
Nominal Bore Is Not the Internal Diameter
The single most common sizing error is to read the millimetre number in a size like “50MM” as a diameter you can measure. It is neither the outside diameter nor the internal diameter — it is a nominal bore, a designation that once loosely described the inside bore in inches and is now just the size’s name. A 50MM pipe is the same size as a 2 inch pipe; its outside diameter is a fixed 60.3mm.
Three dimensions sit behind each size. Nominal bore (NB) is the name. Outside diameter (OD) is the measured outer dimension and is fixed for each size, whatever the class — that is what makes fittings, threads and sockets interchangeable. Internal diameter (ID) is what is left inside, and it equals the outside diameter minus twice the wall thickness, so it shrinks as the class gets heavier.
This is why a plumber sizing a flow works from the class as well as the size, and why a fabricator ordering by outside diameter and wall never gets caught out. The wall thickness by class is set out on the class A, B, C guide.
Common Sizing Mix-Ups
“32mm” is not 32mm OD
32MM is the nominal bore, the same size as 1¼ inch. Its outside diameter is 42.4mm. Order “32mm” expecting a 42.4mm tube, not a 32mm one.
“1 inch” is 25MM, OD 33.7
The 1 inch designation is 25MM nominal bore, outside diameter 33.7mm — not 25.4mm. Inch here names the bore, not the diameter.
mm and inch are the same size
40MM and 1½ inch are one pipe, not two options. The chart above pairs them so a mm quote and an inch quote can be matched.
Sections are sized differently
Square and rectangular hollow sections are called out by outside dimensions, like 40×40 or 80×40 to IS:4923 — not by nominal bore. Section size range →
The safe way to order is to give the nominal bore or the inch size, the class, and the finish (GI or MS). That removes the ambiguity that a bare millimetre number leaves. To match a size from a drawing, send it across and it will be read back in full.
Jindal Pipe Sizes — FAQ
What is the OD of 15MM Jindal pipe?
15MM (half inch) pipe has an outside diameter of 21.3mm to IS:1239. The OD is the same across Light, Medium and Heavy; only the wall thickness changes between classes.
Is 32MM the same as 1-1/4 inch pipe?
Yes — 32MM is the nominal bore in millimetres and 1¼ inch is the same size in the inch designation. Its outside diameter is 42.4mm. The number 32 is neither the outside nor the internal diameter.
Is nominal bore the same as internal diameter?
No. Nominal bore is a size designation, not a measured dimension. The internal diameter is the outside diameter minus twice the wall thickness, so it changes with class — the NB, OD and ID section shows a worked example.
What is the NB to OD chart for Jindal pipe?
To IS:1239: 15MM is 21.3mm, 20MM 26.9mm, 25MM 33.7mm, 32MM 42.4mm, 40MM 48.3mm, 50MM 60.3mm, 65MM 76.1mm, 80MM 88.9mm, 100MM 114.3mm, 125MM 139.7mm and 150MM 165.1mm. The full chart with inch sizes is above.
Why does the OD stay the same across classes?
So fittings, threads and sockets match regardless of class. IS:1239 fixes one outside diameter per size and changes only the wall thickness between Light, Medium and Heavy.
What is the size range of Jindal pipe?
IS:1239 covers 15MM to 150MM; IS:3589 covers 150MM to 300MM at 168.3, 193.7, 219.1, 273.0 and 323.9mm OD. Jindal Hissar goes to 400MM in black and 300MM in GI; Jindal Star goes to 600MM.
How are square and rectangular sections sized?
By outside dimensions, not nominal bore — for example 40×40 or 80×40 in mm, to IS:4923. The section-pipe page lists the range.
Why do I get the wrong pipe when I order by mm?
Because the millimetre number in a size like 32MM is the nominal bore, not a measurable diameter. Ordering “32mm” for a 32mm outside diameter gives the wrong pipe — 32MM is actually 42.4mm OD. State the nominal bore or inch size and the class to avoid it.
Reading a Size Off a Drawing?
List the sizes as they appear on your drawing or BOQ and send them — each will be read back with its nominal bore, inch size and outside diameter.
Vijay Sales Corporation — certified dealer of Jindal Star and Jindal Hissar, stocking at its Delhi warehouse for pan-India supply. This is a reference chart; it carries no prices — see the Jindal Hissar and Jindal Star price lists.
Registered offices: 803 International Trade Tower, Nehru Place, New Delhi-110019 · 3356 Hauz Qazi, Delhi-110006.
GSTIN: 07AAGPG5324D1Z6 · Udyam (MSME) Reg: UDYAM-DL-01-0005438.
Methodology: nominal outside diameters per IS:1239 (Part-1):2004 and IS:3589; internal diameters are outside diameter minus twice the wall, shown as calculations. Dimensions are standard-fixed and identical across compliant makers.