Rectangular Hollow Section

Rectangular Hollow Section

A Rectangular Hollow Section (RHS) is a type of steel profile with a rectangular hollow cross-section throughout its length.

It is commonly used in construction and structural applications due to its strength and versatility.

What are the benefits of rectangular hollow section?

Since rectangular and square HSS have about two-thirds the surface area of an open section of comparable capacity, this has a cost-saving benefit as there is less surface to prepare, fewer painting materials are required, cementitious fireproofing can be reduced, and minimal labour is needed.

What size is a rectangular hollow section?

As a structural section, the Rectangular Hollow Section tube is commonly used. The pipes are produced to give greater strength and solderability. It is 50 mm x 25 mm to 450 mm x 250 mm in size. The width of the wall in larger sections ranges between 2 mm and 20 mm.

Its uniformity makes it predictable to use and visually appealing. It has a high weight-to-strength ratio.

We are manufacturing and exporting Rectangular Hollow Sections, Rectangular Hollow Steel Sections and Rectangular Hollow Section Tubes as per customer's requirement with anti rust oil coating from inside & outside of the tubes to ensure safe delivery to end customers.

Rectangular Tube is commonly available in Aluminium, Stainless Steel, Black Steel and Bright Steel. It can be purchased at any Metal Supermarkets location. It can be cut to your exact specifications.

Specialising in Steel, Cut to Length, Round, Square, Hollow, Rectangular, Rectangular Hollow Sections, RHS

A wide range of dimensions, when combined with the appropriate steel grade, ensure that the functionality and cost-efficiency of your structure can be optimised.

What is RHS in material?

The term RHS stands for Rectangular Hollow Section. RHS is the most prevalent term and is generally accepted for describing square hollow section as well, which is technically incorrect. The correct term for square tube is SHS which stands for Square Hollow Section.

Chemical composition

Steel Grade: Q195, Q215, Q235, Q345, S235JR, S275JR, SS4007-

Data Elements(%)
Materal Grade C Mn S P Si
Q195 0.06-0.12 0.25-0.50 <0.05 <0.045 <0.30
Q215 0.09-0.15 0.25-0.55 <0.05 <0.045 <0.30
Q235 0.12-0.20 0.30-0.70 <0.045 <0.045 <0.30
Q345 <0.20 1.0-1.6 <0.04 <0.04 <0.55

Mechanical property

Materal Grade Yield point (Mpa) Tensile Strength (Mpa) Elongation(%)
Q195 >195 315-430 32-33
Q215 >215 335-450 26-31
Q235 >235 375-500 24-26
Q345 >345 470-630 21-22

Tolerance

Length +/- 50 MM
Wall Thickness +/- 12.5%
Weight +/- 8%

What is the Difference Between Square Tube and Rectangular Tube?

Square tubes and rectangular tubes are two common shapes of hollow structural sections used in various applications like construction, manufacturing, and engineering. The main difference between them lies in their cross-sectional shape:

1. The cross-section differs:
A square tube has a square cross-section, while a rectangular tube has a rectangular cross-section.

2. Different applications:
- Square tube uses: Construction, machinery manufacturing, steel construction projects, shipbuilding, solar power brackets, steel structure engineering, power engineering, power plants, agricultural and chemical machinery, glass curtain walls, automotive chassis, airports, boiler construction, highway railings, building construction, pressure vessels, oil storage tanks, bridges, power station equipment.
- Rectangular tube uses: Transporting fluids such as petroleum, natural gas, water, gas, and steam, especially when requiring bending and torsional strength with low weight. It is also widely used in manufacturing mechanical parts and engineering structures. Additionally, it's used in the production of conventional weapons, barrels, shells, and more.

3. Different coverage scope: A square tube is a type of rectangular tube and is included in the category of rectangular tubes.

Additional Information:
Rectangular tubes are typically produced in two main ways: cold rolling and hot rolling. Hot-rolled rectangular tubes are made by passing hot-rolled strips through a manufacturing process. Cold-drawn or cold-rolled precision tubes are used for mechanical structures and hydraulic equipment, offering high dimensional accuracy and a smooth surface finish.

Many defects in square tubes arise during the perforation process. Therefore, perforation is a critical step in square tube production. Perforation, especially in high-alloy materials, can be challenging due to their low perforation performance. To ensure quality, it's essential to select deformation parameters for perforation carefully.

What does RHS mean in steel?

RHS (rectangular hollow steel) tubing is used for a wide variety of construction and fabrication purposes. This tubing is extremely popular for the construction of furniture, frames, and all sorts of load bearing uses.

Note:

Application:

Furniture industries & domestic applications, bus body, fencing etc. Sizes other than mentioned above can also be produced upon specific requirements.


Hot rolled rectangular steel tube

Hot rolled rectangular steel tube is ideal for structural applications, general fabrication, repairs and manufacturing. Its box-shape design allows for increased strength and rigidity over other shapes of hot rolled steel. Hot rolled rectangular steel tube is easy to cut, weld, form and machine.

Hot rolled rectangular steel tube
Hot rolled rectangular steel tube
Hot rolled rectangular steel tube
Hot rolled rectangular steel tube
Hot rolled rectangular steel tube
Hot rolled rectangular steel tube

Steel rectangular tube is a versatile solution for:

What size pipe is used for solar panels?

As a rule of thumb, a solar thermal installation with up to four collectors needs ¾-inch pipes (1.905 centimeters); up to eight collectors will need 1-inch pipes (2.54 centimeters); anything bigger doesn't have a rule of thumb!

Stainless Hollow Section

Stainless Hollow Section

Stainless hollow sections, also known as stainless steel box sections or stainless steel square hollow sections (SHS), are structural components made of stainless steel with a hollow, square-shaped cross-section.

Type:Stainless Steel Square Tube, Stainless Steel rectangular Tube, Square Hollow Section, Rectangular Hollow Section

Standard:ASTM A554,ASTM A249,ASTM A312,DIN11850,JIS G3459,JIS G3448,GB/T12770,GB/T12771

Steel Grades: 304/304L,316/316L,301,202,201,409,410,430

Surface: Pickled, Bright, Matt, Polished, Mirror.

Application: The high quality Stainless steel rectangular pipe / tube is widely used for building, architecture, industry, safeguard, decoration, tools, etc.

Delivery Special Welded Tubes

Special welded tubes, often used in critical industrial applications, require careful handling and transportation to ensure they reach their destination in optimal condition. These tubes may vary in size, material, and specifications, making their proper delivery essential.

Measure weld stee pipes
Measure weld stee pipes
Measure weld stee pipes

Welded pipes specification and size

API SPEC 5CT

Product Name Executive Standard Dimension (mm) Steel Code / Steel Grade
Casting API 5CT Ø48.3~273 x WT2.77~11.43 J55, K55, N80, L80
Tubing API 5CT Ø48.3~273 x WT2.77~11.43 J55, K55, N80, L80, H40
 

API SPEC 5L

Product Name Executive Standard Dimension (mm) Steel Code / Steel Grade
Line Pipes API 5L Ø60.3~273.1 x WT2.77~12.7 A25, A, B, X42, X46, X52, X56, X60, X65, X70, X80

ASTM / ASME

Product Name Executive Standard Dimension (mm) Steel Code / Steel Grade
Electric-Resistance-Welded Steel Pipes ASTM A135 Ø42.2~114.3 x WT2.11~2.63 A
Electric-Resistance-Welded Carbon Steel and Carbon-Manganese Steel Boiler and Superheater Tubes ASTM A178 42.2-114.3 x 2.11-2.63 A, C, D
ERW and Hot-dip Galvanized Steel Pipes ASTM A53 Ø21.3~273 x WT2.11~12.7 A, B
Pipes for Piling Usage ASTM A252 Ø219.1~508 x WT3.6~12.7 Gr.2, Gr.3
Tubes for General Structural Purpose ASTM A500 Ø21.3~273 x WT2.11~12.7 Gr.2, Gr.3
Square Pipes for General Structural Purpose ASTM A500 25 x 25~160 x 160 x WT1.2~8.0 Carbon Steel
 

DIN

Product Name Executive Standard Dimension (mm) Steel Code / Steel Grade
Threaded Steel Pipes DIN 2440 Ø21~164 x WT2.65~4.85 Carbon Steel

BS

Product Name Executive Standard Dimension (mm) Steel Code / Steel Grade
Screwed and Socketed Steel Tubes BS 1387 Ø21.4~113.9 x WT2~3.6 Carbon Steel

EN

Scaffolding Pipes EN 39 Ø48.3 x WT3.2~4 Carbon Steel

JIS

Product Name Executive Standard Dimension (mm) Steel Code / Steel Grade
Carbon Steel Tubes for General Structure Purpose JIS G3444 Ø21.7~216.3 x WT2.0~6.0 Carbon Steel
Carbon Steel Tubes for Machine Structure Purpose JIS G3445 Ø15~76 x WT0.7~3.0 STKM11A, STKM13A
Carbon Steel Pipes for Ordinary Piping JIS G3452 Ø21.9~216.3 x WT2.8~5.8 Carbon Steel
Carbon Steel Pipes for Pressure Service JIS G3454 Ø21.7~216.3 x WT2.8~7.1 Carbon Steel
Carbon Steel Rigid Steel Conduits JIS G8305 Ø21~113.4 x WT1.2~3.5 G16~G104, C19~C75, E19~E75
Carbon Steel Rectangular Pipes for General Structure JIS G3466 16 x 16~150 x 150 x WT0.7~6 Carbon Steel
Alloy Steel Pipe Inventory Alloy Steel Pipe Inventory

Advantage of ERW pipe

The alloy content of the coil is often lower than similar grades of steel plate, improving the weldability of the spiral welded pipe. Due to the rolling direction of spiral welded pipe coil is not perpendicular to the pipe axis direction, the crack resistance of the spiral welded pipe materials.

What is welded steel pipe?

Welded steel pipe refers to a steel pipe with seams on the surface that is welded by bending and deforming a steel strip or steel plate into a circular, square or other shape. The blanks used for welded steel pipes are steel sheets or strips.

Since the 1930s, with the rapid development of continuous rolling production of high-quality strip steel and the advancement of welding and inspection technology, the quality of welds has been continuously improved, and the varieties and specifications of welded steel pipes have been increasing.

When the T-shaped welded steel pipe contains Ni, it has strong corrosion resistance in an acidic environment. In an environment containing sulfuric acid or hydrochloric acid, the higher the Ni content in the T-shaped welded steel pipe, the stronger the corrosion resistance. Under normal circumstances, only adding Cr to the T-shaped welded steel pipe can prevent the phenomenon of corrosion. The poor edge condition of the strip is another important cause of misalignment. The effects of changes in mass flow, heat flow density and structural parameters (ratio of helical curvature diameter to T-shaped welded steel pipe diameter Dc/D) on the heat transfer coefficient of saturated bubble boiling in vertical spiral pipes.

During the production of T-shaped welded steel pipes, misalignment occurs from time to time, and there are many influencing factors. In production practice, the steel pipe is often degraded by the wrong side and out of tolerance. Therefore, it is necessary to analyze the reasons for the misalignment of the spiral steel pipe and its preventive measures.

Due to the poor shape and dimensional accuracy of the head and tail of the uncut steel strip, it is easy to cause the steel strip to bend hard and cause misalignment during butt joint. Simulation parameter range: vertical pipe: pipe diameter D=10mm, pipe length L=660mm; three types of vertical T-shaped welded steel pipe: pipe diameter D=10mm, the change of the ratio of the curvature diameter of the T-shaped welded steel pipe to the spiral pipe diameter is Dc /D=15, 20, 25, helical pitch Pt=20mm, tube lengths are L=503mm, L=660mm, L=817mm respectively. Mass flow G=200~400Kg/(m'2 s), heat flux density q=5~15KW/m'2, saturation pressure p, saturation=0.414880MPa, saturation temperature T, saturation=283.15K.

Technical requirements for welded pipes

The technical requirements and inspection of welded pipes are based on the provisions of the GB3092 "Welded Steel Pipes for Low-Pressure Fluid Transmission". It can be delivered according to fixed length or double length. The surface of the steel pipe should be smooth, and defects such as folds, cracks, delamination, and lap welding are not allowed. The surface of the steel pipe is allowed to have minor defects such as scratches, scratches, weld misalignment, burns and scars that do not exceed the negative deviation of the wall thickness. The thickening of the wall thickness and the presence of inner seam weld bars are allowed at the weld.

Welded steel pipes should be subjected to mechanical performance test, flattening test and flaring test, and must meet the requirements of the standard. When the steel pipe should be able to withstand the internal pressure, carry out a pressure test of 2.5Mpa, and keep it for one minute without leakage. The method of eddy current flaw detection is allowed to replace the hydrostatic test. The eddy current flaw detection is carried out according to the standard of GB7735 "Steel tube eddy current flaw detection inspection method". The eddy current flaw detection method is to fix the probe on the frame, keep a distance of 3~5mm between the flaw detection and the weld seam, and conduct a comprehensive scan of the weld seam by the rapid movement of the steel pipe. The flaw detection signal is automatically processed and sorted by the eddy current flaw detector. To achieve the purpose of flaw detection. The welded pipe after the flaw detection is cut off according to the specified length with a flying saw, and it is rolled off the assembly line through the turning frame. Both ends of the steel pipe should be chamfered with flat ends, printed with marks, and the finished pipes are packed in hexagonal bundles before leaving the factory.

Straight seam steel pipe processing method:

Straight seam steel pipe is a steel pipe whose weld seam is parallel to the longitudinal direction of the steel pipe. Generally, its strength is higher than that of straight seam welded pipe. Narrower billets can be used to produce welded pipes with larger diameters, and the same width of billets can be used to produce welded pipes with different pipe diameters. But compared with the straight seam pipe of the same length, the weld length is increased by 30~100%, and the production speed is lower. So what are its processing methods?

  1. Forging steel: a pressure processing method that uses the reciprocating impact force of the forging hammer or the pressure of the press to change the blank into the shape and size we need.
  2. Extrusion: It is a processing method in which steel puts metal in a closed extrusion box and applies pressure at one end to make the metal extrude from the specified die hole to obtain a finished product with the same shape and size. It is mostly used for the production of non-ferrous metals material steel.
  3. Rolling: A pressure processing method in which the steel metal billet passes through the gap between a pair of rotating rolls (various shapes), and the cross-section of the material is reduced due to the compression of the rolls, and the length is increased.
  4. Pulling steel: it is a processing method in which the rolled metal blank (type, pipe, product, etc.) is pulled through the die hole to reduce the cross section and increase the length. Most of them are used for cold processing.

Quenching Technology for Straight Seam Welded Pipe

The surface quenching and tempering heat treatment of straight seam welded pipe is usually carried out by induction heating or flame heating. The main technical parameters are surface hardness, local hardness and effective hardened layer depth. Vickers hardness tester can be used for hardness testing, and Rockwell or superficial Rockwell hardness tester can also be used. When the surface heat treatment hardened layer is thick, the Rockwell hardness tester can also be used. When the thickness of the heat-treated hardened layer is 0.4-0.8mm, the HRA scale can be used, and when the thickness of the hardened layer exceeds 0.8mm, the HRC scale can be used.

If the parts require high local hardness, local quenching heat treatment can be carried out by means of induction heating. Such longitudinal welded pipes usually need to mark the location of local quenching heat treatment and local hardness value on the drawing. Hardness testing of longitudinally welded pipes shall be carried out in the area. The hardness testing instrument can use a Rockwell hardness tester to test the HRC hardness value. If the heat-treated hardened layer is shallow, a surface Rockwell hardness tester can be used to test the HRN hardness value.

The three hardness values of Vickers, Rockwell and Superficial Rockwell can be easily converted to each other and converted into hardness values required by standards, drawings or users. The corresponding conversion tables are given in the international standard ISO, the American standard ASTM and the Chinese standard GB/T.

【H】 Ceramic lined pipe

Ceramic lined pipe is made through self-propagating high-temperature synthesis (SHS) technique.

【H】 Cast basalt lined steel pipe

Cast basalt lined steel pipe is composed by lined with cast basalt pipe, outside steel pipe and cement mortar filling between the two layers.

【H】 Ceramic Tile Lined Pipes

Ceramic tile lined pipes have very uniform coating of specially formulated ceramic material that is affixed to the inner of the pipe.

【H】 Rare earth alloy wear-resistant pipe

The material of the rare earth alloy wear-resistant pipe is ZG40CrMnMoNiSiRe, which is also the grade of rare earth alloy steel.

【H】 Tubes Erosion Shields

Tubes Erosion Shields are used to protect boiler tubing from the highly erosive effects of high temperatures and pressures thereby greatly extending tube life.

【H】 ASTM A213 T91 Alloy Tube

The ASTM A213 T91 seamless tubes are primarily used for boiler, superheater, and heat-exchanger.