MUST-KNOW: 15 Differences Between Pipes and Tubes

At the first sight, pipe and tube looks the same. There are many similarity for pipes and tubes: all made of metal, with same shape, and all hollow… But there are many difference between them. Let’s see the 

15 Difference Between Pipe and Tube

1. Pipe Diameter and Tube Diameter
Pipe diameter refers to a nominal diameter- not actual. Pipe Schedule refers to the pipe’s wall thickness (you can find the schedule chart and specification). The actual physical outside diameter is larger than it’s nominal OD.
The diameter of tubing on the other hand refer to the actual outside diameter. In other words, the actual physical OD of a tube is just the same as it’s nominal OD.
For example: The actual outside diameter of 1¼” pipe is 1.625″ – while 1¼″ tube has a true 1.25″ outside diameter.
Pipes accommodate larger applications with sizes that range from a half-inch to several feet. Tubes are generally used in applications that require smaller diameters. While 10-inch pipes are common, it’s rare that you will come across a 10-inch tube.

2. Wall Thickness Difference 

The wall thickness of pipes and tubes is an important factor to tell difference. The thickness of tubing is often specified by a gauge for thinner thicknesses and for thicker tubing it is indicated by fractions of an inch or millimeters. The normal range for tubing is 20 gauge, which measures .035 inch, up to a thickness of 2 inches. The wall thickness of a pipe is referred to as a pipe schedule, which you can find the relevant between pipe schedule and thickness in millimeter or inch in specification ASME B36.10. The most common schedules are SCH 20,SCH 40 and SCH 80. Schedule 40 is the most common and 80 is extra heavy. Which is needed to be noted, the pipe schedule is not set for all diameters; it varies.

For example:  

Diameter 8inch/219.1 pipe, pipe schedule is SCH 40 = wall thickness is 0.322inch/8.18mm, 

Diameter 12 inch /323.9 pipes, sch 40 refers wall thickness of 0.406inch/10.31mm.

There is no formula between the pipe schedule and wall thickness, the only is to refer to the ASME B36.10 or relevant standards.

3. Pipes Tolerance & Tube Tolerance
Pipes are usually used for transporting or distributing, then the properties of pressure or straightness, roundness are strictly specified, the tolerance for pipes is more loose than tubes comparatively. Here the tolerance refers to diameter tolerance, wall thickness tolerance, straightness tolerance, roundness tolerance etc.

4. Manufacturing Difference of pipes and tubes
As we mentioned above, tubes will require higher level requirements, consequently, even from the material producing to the pipe or tube manufacturing process will be different. Tubes will require much more process, tests, inspection than pipes. The delivery time will be longer, too. The yield of tubes are comparatively much lower than pipes. Pipe manufacturing is easier compare to tubes and it’s in mass production

5. Cost & Price
As per to the above, to manufacture tubes will take much more labor, energy, material etc, so the production cost is surely higher than pipes. And just because the high level requirement of tubes, the low yield of tubes will also increase the cost and price. While the process of pipes is easier. And pipes  are manufactured in large lot and cut the cost.

6. Use of Pipes and Tubes
Pipes are used for fluids and gases, such as water, oil, gas or propane or as steam pipe, boiler pipe etc. Just because of this, the outside & inside diameter is the key measurement — it indicates how much can flow through the pipe. Also that’s the reason why the pressure rating is so important, because the pressure must be under the transport or distribute pressure range. Tubes, however, are often put to use in applications that require precise outside diameters, like with medical tubes, weapon part, industrial parts, cooler tubes, heat exchanger tubes and boiler tubes. Tubes are usually used in medical area, construction, structure or load bearing etc. This is why the outside diameter is important because it indicates how much it can hold as a stability factor.

7. Material
Piping is usually made of carbon steel or low alloy steel. while tubing is often made of mild steel, aluminum, brass, copper, chrome or stainless steel etc. Different material also lead to different cost and price.

8. Mechanical Properties and Chemical Properties
For pipes the pressure rating, yield strength, ductibility properties are more important. However, for tubes, the hardness, tensile strength, high precision is the key to high quality. Those elements like C, Mn, S, P, Si are the main chemical elements for pipes, and there is few microelements requirements . While for tubing, the microelements are very important to the quality and process.  

9 Connection /Join Welding
Connecting pipes is more labor intensive as it requires welding, threading or flanges and relevant equipments. Tubes can be joined quickly and easily with flaring, brazing or couplings, but for this reason, they don’t offer the same stability. Pipe welding is safer than “tube join”.

10. Ductibility

Pipe is available in rigid “joints”, which come in various lengths depending on the material. Tubing, in particular copper, comes in rigid hard tempered “joints” or soft tempered (annealed) rolls. Some tubing also comes in rigid “joints” or flexible rolls. The temper of the copper, that is whether it is a rigid “joint” or flexible roll, does not affect the sizing. 

11. Packing
Pipes to delivered are in bundle or just bulk delivery. Because we just need to protect the pipes surface from serious damage and no need to protect from any light chafing. While tubes are usually wrapped with wooden box or thin film for each tube, especially for medical area tube.

12. Surface Finish

For outdoor field transporting or underground transporting, pipes need to be painted or coating to anti corrosion or oxidation. Tubes are sour cleaning or special polish treatment for particular field use.

13. Quantity

For long transport or distributing, piping is often used in mass quantity and for long distance application. So, the order of pipes are usually large. While tubes may be used in small quantity.

14. Pipe End and Tube End
Pipe ends are usually in plain or beveled so as to welding. while tubes are with coupling ends or specially end finish, like irregular ends, special screw thread etc.

15. Application
Pipes accommodate larger applications with sizes that range from a half-inch to several feet. Tubes are generally used in applications that require smaller diameters. While 10-inch pipes are common, it’s rare that you will come across a 10-inch tube.

Reference:

Difference between Pipes and Tubes

Differences Between Tubing & Pipe

Water pipe-WIKI

Pipes vs. Tubes – Is There a Difference?

Pipe Vs Tube

Original:http://www.hysteelpipe.com/steel-knowledge/15-difference-pipe-tube/

API 5L B / ASTM A53 B SCH40 Steel Tube

HYSP produce sch 10, sch 20, sch 30. sch 40, sch 80 welded tubes.  And we are strong at tuberia astm a53 sch 40 carbon pipes, astm a53 sch 40 tubes. Besides the API 5L Grade B welded pipes, the ASTM A53 B SCH40 Welded Tubes are the second popular pipe products in HYSP.

You are welcome to send us your RFQ and we will send the A53 B pipe price asap.

A53 B SCH40 Steel Tube

Product Name	ASTM A53 B SCH40 Welded Tube
A53 B SCH40 pipe Diameter	1inch, 4inch, 6 inch, 8 inch, ~ 26 inch
Diameter Tolerance	acc. to ASTM A53, +/-1% of outside diameter
Wall Thickness	STD,SCH 30, SCH40, SCH 80, SCH 120, SCH 180etc.
Wall Thickness Tolerance	acc. to ASTM A53, +/- 12.5%t
Pipe Standard	ASTM A53, API 5L, CSA Z245, A106, ASTM A252, AS 1163, IPS 190 etc
A53 B SCH40 pipe Grade	Grade A, Grade B or other steel grade required
A53 B SCH40 pipe Test	Hydro test, UT test, Flatten test, Impact test, DWT test if agreed etc
Hydro test pressure	As per ASTM A53 Spec
A53 B SCH40 pipe Length	SRL, DRL, Random length from 3m to 18m
End Finish	Bevelled ends with caps or steel protector
Application	Fluid pipe, line pipe, water pipe, structure steel tube, piling pipe, construction pipe, bridge pipe etc.
Pipe Coating	Black painting, varnish, anti rust oil, FBE, 3PE, 3 layer PE, 3PP etc.
Package	Plastic caps on both ends, Steel bundle, or acc. to customers’ request
Inspection	ISO9001, SGS,BV, GL, DNV, Moody  or other TPI appointed by customer
Capacity	10000 metric tons per month
Delivery time	30 days against deposit or LC at sight

Carbon Steel Pipe Schedule Chart Dimension -- ASME B36.10M-2004

Welded and Seamless  Wrought Steel Pipe–Steel Pipe Schedule Chart

-ASME B36.10M-2004

CONTENTS

Foreword . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iv

Committee Roster . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vi

1 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

2 Size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

3 Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

4 Wall Thickness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

5 Weights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

6 Permissible Variations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

7 Pipe Threads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

8 Wall Thickness Designations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

9 Wall Thickness Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Table

1 Dimensions and Weights of Welded and Seamless Wrought Steel Pipe . . . . . . . . . . . . . . . 3

1. Scope

This Standard covers the standardization of dimensions of welded and seamless wrought steel pipe for high or low temperatures and pressures. 

The word pipe is used, as distinguished from tube, to apply to tubular products of dimensions commonly use for pipeline and piping systems. Pipe NPS 12 (DN 300) and smaller have outside diameters numerically larger than their corresponding sizes. In contrast, the outside diameters of tubes are numerically identical to the size number for all sizes.

2. Size

The size of all pipe is identified by the nominal pipe size.The manufacture of pipe NPS 1⁄8 (DN 6) to NPS 12

(DN 300), inclusive, is based on a standardized outside diameter (OD). This OD was originally selected so that pipe with a standard OD and having a wall thickness that was typical of the period would have an inside diameter (ID) approximately equal to the nominal size. Although there is no such relation between the existing standard thickness — OD and nominal size — these nominal sizes and standard ODs continue in use as ‘‘standard.’’ The manufacture of pipe NPS 14 (DN 350) and larger proceeds on the basis of an OD corresponding to the nominal size.

API 5L Line Pipe 8 inch SCH 40 ERW Welded Steel Tube

API 5L Line Pipe 8 inch SCH 40 Welded Tube

O.D	O.D tolerance	W.T tolerance
1/2"-26"	±0.03	±10%
Length	3--18M , according to customers' requirements
International Standard	ISO 9001;2000 API 5L, ASTM A53, A252, EN10219,  GB  etc.
Standard	ASTM A53 A106  / BS 1387-1985 GB5310-1995 API 5L
Material	Q235/Q345 GR.B X42 X46 X52 X60 X65 X70 X80, GRADE 1, GRADE 2, GRADE 3
Product  Usage	8 inch SCH 40 Welded Tube Fluid pipe, boiler ,hydraulic, gas,oil,chemical fertilizer, structure pipes etc. 1.For low pressure liquid delivery such as water , gas and oil 8 inch SCH 40 Welded Tube 2.For construction , example:  building greenhouse
Making method	cold drawing,hot rolling,hot expanded
Packing	Bevelled ends /plain ends , varnish coating, marking, plastic caps for end protecting ,pacing In bundles according to customers' requirements
Main market:	Middle east, Africa, North and South America, East and West Europe, South ,southeast Asia, Australia and so on
Place of Origin	Hebei, China
Productivity	10000 Ton/Month
Processing technology available:	Threading , coupling and with plastic caps protected
Remarks	1) Payment : TT, LC etc 2) Trade Terms : FOB / CFR /CIF 3) MOQ : 25T  4) Delivery period: accordin to the material ,the standard, and the quanitty of the contract.(will be informed in the quotation sheet)

EN10210 S355joh Mild Steel Pipe

EN10210 S355joh Mild Steel Pipe Specifications

Our company HYSP is a professional manufacturer specializing in producing ERW EN10210 S355joh Mild Steel Pipe. We can supply EN10210 S355joh Mild Steel Pipe with the standards of GB, ASTM A53, ASTM A252, API 5L. Besides, we also have perfect production lines and skilled engineers to manufacture these products.

These S355joh Mild Steel Pipe products are manufactured to meet the mechanical property requirements of all international S355joh Mild Steel Pipe standards and are suitable for welding and limited bending. 

The S355joh Mild Steel Pipe plant process a wide range of S355joh Mild Steel Pipe hollow sections to local and international specifications. Typical applications include agricultural, architectural, general engineering, mechanical handling and structural uses. Typical uses are agricultural implement frames, trailers, pallets and stock crates, sign gantries, service bridges, railings, columns and trusses.

EN10210 S355joh Mild Steel Pipe

Product name		EN10210 ERW  S355joh Mild Steel Pipe
	Out diameter	21-660mm
specification	thickness	4mm-25mm
	length	6-18m or others according to the client
Steel material		A53 Grade B, API 5L X42, X46, X52, X56,X60, X65, X70 etc
usage		used for gas, petroleum, water ,oil and other liquid transportation or construction
ends		plain or beveled(can be protected by plastic pipe cap)
surface		bared or paint with oil, bitumen,1-3 layer PE (outside or inside anti-corrosion treatment can supply)
Inspection		with hydraulic testing, eddy current , infrared or X-Ray test
		also with chemical and physical property inspect
technique		ERW welded pipe
type		welded
Welded line type		longitudinal welding
Section shape		round
package		in bulk, or other methods according to the client
Payment term		T/T or L/C
Delivery time		20-30 days after deposit or according to the quantity
Place of origin		Tianjin, China
Main market		Middle East,Africa, Southeast Asia, European and South America

EN10210 S355joh Mild Steel Pipe

Steel Pipe Manufacturing Process

Overview:

The manufacture of steel pipe dates from the early 1800’s. Initially, pipe was manufactured by hand – by heating, bending, lapping, and hammering the edges together. The first automated pipe manufacturing process was introduced in 1812 in England. Manufacturing processes have continually improved since that time. Some popular pipe manufacturing techniques are described below.

Lap Welding

The use of lap welding to manufacture pipe was introduced in the early 1920’s. Although the method is no longer employed, some pipe that was manufactured using the lap welding process is still in use today.

In the lap welding process, steel was heated in a furnace and then rolled into the shape of a cylinder. The edges of the steel plate were then “scarfed”. Scarfing involves overlaying the inner edge of the steel plate, and the tapered edge of the opposite side of the plate. The seam was then welded using a welding ball, and the heated pipe was passed between rollers which forced the seam together to create a bond.

The welds produced by lap welding are not as reliable as those created using more modern methods. The American Society of Mechanical Engineers (ASME) has developed an equation for calculating the allowable operating pressure of pipe, based on the type of manufacturing process. This equation includes a variable known as a “joint factor”, which is based on the type of weld used to create the seam of the pipe. Seamless pipes have a joint factor of 1.0. Lap welded pipe has a joint factor of .6.

Electric Resistance Welded pipe manufacturing

Electric resistance welded (ERW) pipe is manufactured by cold-forming a sheet of steel into a cylindrical shape. Current is then passed between the two edges of the steel to heat the steel to a point at which the edges are forced together to form a bond without the use of welding filler material. Initially this manufacturing process used low frequency A.C. current to heat the edges. This low frequency process was used from the 1920’s until 1970. In 1970, the low frequency process was superseded by a high frequency ERW process which produced a higher quality weld.

Over time, the welds of low frequency ERW pipe was found to be susceptible to selective seam corrosion, hook cracks, and inadequate bonding of the seams, so low frequency ERW is no longer used to manufacture pipe. The high frequency process is still being used to manufacture pipe for use in new pipeline construction.

Electric Flash Welded pipe manufacturing

Electric flash welded pipe was manufactured beginning in 1927. Flash welding was accomplished by forming a steel sheet into a cylindrical shape. The edges were heated until semi-molten, then forced together until molten steel was forced out of the joint and formed a bead. Like low frequency ERW pipe, the seams of flash welded pipe are susceptible to corrosion and hook cracks, but to a lesser extent than ERW pipe. This type of pipe is also susceptible to failures due to hard spots in the plate steel. Because the majority of flash welded pipe was produced by a single manufacturer, it is believed these hard spots occurred due to accidental quenching of the steel during the manufacturing process used by that particular manufacturer. Flash welding is no longer used to pipe manufacturing.

Double Submerged Arc Welded (DSAW) pipe manufacturing

Similar to other pipe manufacturing processes, the manufacture of Double Submerged Arc Welded Pipe involves first forming steel plates into cylindrical shapes. The edges of the rolled plate are formed so that V-shaped grooves are formed on the interior and exterior surfaces at the location of the seam. The pipe seam is then welded by a single pass of an arc welder on the interior and exterior surfaces (hence double submerged). The welding arc is submerged under flux.

The advantage of this process is that welds penetrate 100% of the pipe wall and produce a very strong bond of the pipe material.

Seamless pipe manufacturing

Seamless pipe has been manufactured since the 1800’s. While the process has evolved, certain elements have remained the same. Seamless pipe is manufactured by piercing a hot round steel billet with a mandrel. The hollowed steel is than rolled and stretched to achieve the desired length and diameter. The main advantage of seamless pipe is the elimination of seam-related defects; however, the cost of pipe manufacturing is greater.

Early seamless pipe was susceptible to defects caused by impurities in the steel. As steel-making techniques improved, these defects were reduced, but they have not been totally eliminated. While it seems that seamless pipe would be preferable to formed, seam-welded pipe, the ability to improve characteristics desirable in pipe is limited. For this reason, seamless pipe is currently available in lower grades and wall thicknesses than welded pipe.

Conclusion

Continual advances in materials and welding techniques have resulted in dramatic improvements in the reliability of pipes. As mentioned, however, there is still pipe in use that is susceptible to corrosion and seam-related defects. These defects are identified through integrity assessments and are repaired when found.

pipe manufacturing today is subject to non-destructive tests such as ultrasonic testing and x-ray, as well as pressure-testing. Each individual section of pipe must be pressure-tested by the manufacturer, and new pipelines are also pressure-tested during the actual construction process.

steel pipe manufacturing techniques 

US keeps antidumping duties on Chinese steel threaded rod, malleable iron pipe

The US government determined on Tuesday that it would maintain the existing antidumping duty orders on steel threaded rod and malleable iron pipe fittings from China, despite Beijing's repeated calls for Washington to drop protectionism.

The US International Trade Commission (ITC) concluded in a ruling that revoking the current antidumping duty orders on these products from China would be likely to lead to continuation or recurrence of material injury within a reasonably foreseeable time.

It is the first "sunset review" for the antidumping duty order on imports of steel threaded rod from China, which was introduced in 2009. The antidumping duty margin on this product runs from 47. 37% to 206%.

This is the second "sunset review" for the antidumping duty order on imports of malleable iron pipe fittings from China, which was first issued in 2003. The antidumping duty margin on the product runs up to 111.36%.

A "sunset review" was conducted every five years after anti-dumping and countervailing duties were introduced. The Uruguay Round Agreements Act requires the US Department of Commerce to revoke an anti-dumping or countervailing duty order, or terminate a suspension agreement, after five years unless the department and the ITC determine that revoking the order or terminating the suspension agreement would likely lead to the continuation or recurrence of dumping or subsidies and of material injury within a reasonably foreseeable time.

The Chinese Ministry of Commerce has repeatedly urged the United States to abide by its commitment against trade protectionism and work together with China and other members of the international community to maintain a free, open and just international trade environment.

US keeps antidumping duties on Chinese steel

ASTM A53 B ERW Steel Tubing

ASTM A53 B ERW Steel Tubing, as the HYSP most popular product, is manufactured as per ASTM A53 B ERW standard which covers seamless and welded black and hot-dipped galvanized steel pipe in NPS 1⁄8 to NPS 26 [DN6 to DN 650].

Under this standard, there are many test needed to be done to ensure the quality of ASTM A53 B ERW Steel Tubing.

ASTM A53 B ERW Product Analysis

The purchaser is permitted to perform an analysis of two ASTM A53 B ERW Steel Tubing from each lot of 500 lengths, or fraction thereof. Samples for chemical analysis, except for spectrographic analysis, shall be taken in accordance with Practice E 1806. The ASTM A53 B ERW Steel Tubing chemical composition thus determined shall conform to the requirements given in Table 1 as above.

Mechanical Properties

Tension Test

Bend Test

If ordered for close coiling, the ASTM A53 B ERW Steel Tubing shall stand being bent cold through 180° around a cylindrical mandrel, the diameter of which is eight times the specified outside diameter of the ASTM A53 B ERW Steel Tubing, without failure.

Flattening Test

The flattening test shall be made on welded pipe over NPS 2 [DN 50] in extra-strong weight or lighter.

Seamless Pipe:

Although testing is not required, ASTM A53 ERW Steel Tubing shall be capable of meeting the flattening test requirements of Supplementary Requirement S1, if tested.

Electric-Resistance-Welded Pipe:

A test specimen at least 4 in. [100 mm] in length shall be flattened cold between parallel plates in three steps, with the weld located either 0° or 90° from the line of direction of force as required by 7.3.3.2 or 7.3.3.3, whichever is applicable.

ASTM A53 B ERW PIPE

Hydrostatic Test

The hydrostatic test shall be applied, without leakage through the weld seam or the ASTM A53 B ERW Steel Tubing body.

Plain-end ASTM A53 B ERW Steel Tubing shall be hydrostatically tested to the applicable pressure given in Table X2.2, and threaded-andcoupledASTM A53 B ERW Steel Tubing shall be hydrostatically tested to the applicable pressure.

Nondestructive Electric Test

The weld seam of each length of electric-resistancewelded ASTM A53 ERW Steel Tubing NPS 2 [DN 50] or larger shall be tested with a nondestructive electric test in accordance with Practices E 213, E 273.

ASTM A53 B ERW Steel Tubing Specification

Product Name	ASTM A53 B ERW Steel Tubing
Diameter	1inch – 26inch
Wall Thickness	SCH10,SCH20,SCH30,STD,SCH40, SCH 80 etc
Length	Random length from 3m to 18m
Pipe Standard	ASTM A53, A106, API 5L,ASTM A500, EN10219, EN10210 etc
Steel Grade	GR A, GR B, X42, X52, S275J0H, S275JRH, S275J2H, S355J0H, S355JRH,
Test	Hydro test, UT test, Flatten test, Impact test etc
Application	industrial pipes, structure steel tube, system pipe, piling tube,
Pipe Coating	Black painting, varnish paint, anti rust oil, or other coating required
Package	Plastic caps on both ends, Steel bundle, or acc. to customers’ request
Inspection	ISO9001, SGS,BV, GL  or other TPI appointed by customer
Capacity	10000 metric tons per month
Delivery time	30 days against deposit or LC at sight