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ASTM A335 P91 Alloy pipe

ASTM A335 Grade P91 pipe is premium grade pipe applied for high pressure boiler. And P91 pipe is ideal when it comes to bending, flanging or when it is used in similar operations such as welding.

Please send your inquiry by   sales@sunnysteel.com

Description

ASTM A335 Grade P91 pipe is premium grade pipe applied for high pressure boiler. And P91 pipe is ideal when it comes to bending, flanging or when it is used in similar operations such as welding.

ASTM A335 Grade P91 pipe is premium grade pipe applied for high pressure boiler. And P91 pipe is ideal when it comes to bending, flanging or when it is used in similar operations such as welding. The material of steel should stick to the composition of chemicals, tensile property and the requirements of hardness.

ASTM A335 P91 alloy steel pipe and high pressure boiler pipes are the two variants available and the range is dependent based on the size, which is solely based on the usage. The length of the pipe will be subject to hydrostatic test and there will also be a non-destructive examination based on the specifications.

ASTM A335 P91 high pressure semaless boiler pipe, The range of ASTM A335 P91 seamless alloy steel pipe sizes that may be examined by each method shall be subjected to the limitations in the scope of the respective practice.

  • Outer Dimensions: 19.05mm – 114.3mm
  • Wall Thickness: 2.0mm – 14 mm
  • Length: max 16000mm

Steel grade: ASTM A335 P91

Chemical Composition(%) ASTM A335

ASTM Specification pipe confirming to ASTM A335 shall have the following chemical properties. Tensile and Hardness Requirements The tensile properties of the ASTM A335 pipe shall conform to the requirements as prescribed. Pipe of Grades P91, P92, and P122 shall have a hardness not exceeding 250 HB/265 HV [25 HRC]. For pipe of Grades P91, P92, P122, and P911, Brinell, Vickers, or Rockwell hardness tests shall be made on a specimen from each lot (see Note 7). These pipe bear high resistance to rupture at high temperature and pressures. With hydrogen crack resistance and sulfide stress corrosion cracking chrome moly pipe are highly preferred over Carbon pipe.
GradeUNC≤MnP≤S≤Si≤CrMo
P1K115220.10~0.200.30~0.800.0250.0250.10~0.500.44~0.65
P2K115470.10~0.200.30~0.610.0250.0250.10~0.300.50~0.810.44~0.65
P5K415450.150.30~0.600.0250.0250.54.00~6.000.44~0.65
P5bK515450.150.30~0.600.0250.0251.00~2.004.00~6.000.44~0.65
P5cK412450.120.30~0.600.0250.0250.54.00~6.000.44~0.65
P9S504000.150.30~0.600.0250.0250.50~1.008.00~10.000.44~0.65
P11K115970.05~0.150.30~0.610.0250.0250.50~1.001.00~1.500.44~0.65
P12K115620.05~0.150.30~0.600.0250.0250.50.80~1.250.44~0.65
P15K115780.05~0.150.30~0.600.0250.0251.15~1.650.44~0.65
P21K315450.05~0.150.30~0.600.0250.0250.52.65~3.350.80~1.60
P22K215900.05~0.150.30~0.600.0250.0250.51.90~2.600.87~1.13
P91K915600.08~0.120.30~0.600.020.010.20~0.508.00~9.500.85~1.05
P92K924600.07~0.130.30~0.600.020.010.58.50~9.500.30~0.60

Chrome Moly Pipes: Werkstoff vs EN vs ASTM

ASTM A335 pipe may be either hot finished or cold drawn with the finishing treatment as required in Grade P2 and P12 – The steel shall be made by coarse- grain melting practice. Specific limits, if any, on grain size or deoxidation practice shall be a matter of agreement between the manufacturer and purchaser.
Werkstoff /DINENASTM
1.541516Mo3A335 Grade P1
1.733513CrMo4-5A335 Grade P11, P12
1.73810CrMo9-10A335 Grade P22
1.7362X11CrMo5A335 Grade P5
A335 Grade P9
1.4903X10CrMoVNb9-1A335 Grade P91

Tensile Requirements

Tensile Strength, min., psiP-5P-9P-11P-22P-91
ksi6060606085
MPa415415415415585
Yield Strength, min., psi
ksi3030303060
MPa205205205205415
Product Analysis At the request of the purchaser, an analysis of two pipe from each lot shall be made by the manufacturer. A lot of ASTM A335 pipe shall consist of the following: NPS Designator Under 2 400 or fraction thereof 2 to 5 200 or fraction thereof 6 and over 100 or fraction thereof.
Note: ASTM A335 P91 shall not have a hardness not exceeding 250 HB/265 HV [25HRC].

Mechanical properties of ASTM A335

Grade Tensile strength Yield strength
 P1,P2 380 205
 P12 415 220
 P23 510 400
 P91 585 415
 P92,P11 620 440
 P122 620 400
A335 is often called chrome moly pipe because of the chemical makeup of Molybdenum (Mo) and Chromium (Cr). Molybdenum increases the strength of steel as well as the elastic limit, resistance to wear, impact qualities, and hardenability. Moly increases the resistance to softening, restrains grain growth and makes chromium steel less susceptible to embrittlement. Moly is the most effective single additive that increases high temperature creep strength.

It also enhances the corrosion resistance of steel, and inhibits pitting. Chromium (or chrome) is the essential constituent of stainless steel. Any steel with 12% or more Chrome is considered stainless. Chrome is virtually irreplaceable in resisting oxidation at elevated temperatures. Chrome raises the tensile, yield, and hardness at room temperatures. The composition chrome moly alloy steel pipe make it ideal for use in power plants, refineries, petro chemical plants, and oil field services where fluids and gases are transported at extremely high temperatures and pressures.

Heat Treatment Requirements

GradeHeat Treatment Type
P5, P9, P11, and P22
Normalizing Temperature Range F [C]Subcritical Annealing or Tempering
Temperature Range F [C]
A335 P5 (b,c)Full or Isothermal Anneal
Normalize and Temper*****1250 [675]
Subcritical Anneal (P5c only)*****1325 – 1375 [715 - 745]
A335 P9Full or Isothermal Anneal
Normalize and Temper*****1250 [675]
A335 P11Full or Isothermal Anneal
Normalize and Temper*****1200 [650]
A335 P22Full or Isothermal Anneal
Normalize and Temper*****1250 [675]
A335 P91Normalize and Temper1900-1975 [1040 - 1080]1350-1470 [730 - 800]
Quench and Temper1900-1975 [1040 - 1080]1350-1470 [730 - 800]

Each length of pipe shall be subjected to the hydrostatic test. Also, each pipe shall be examined by a non-destructive examination method in accordance to the required practices.

The different mechanical test requirements for pipes, namely, transverse or longitudinal tension test, flattening test, and hardness or bend test are presented.Both ends of each crate will indicate the order no., heat no., dimensions, weight and bundles or as requested.

Material & Manufacture

Pipe may be either hot finished or cold drawn with the finishing heat treatment noted below.

Heat Treatment
  • A / N+T
  • N+T / Q+T
  • N+T
Mechanical Tests Specified
  • Transverse or Longitudinal Tension Test and Flattening Test, Hardness Test, or Bend Test
  • For material heat treated in a batch-type furnace, tests shall be made on 5% of the pipe from each treated lot. For small lots, at least one pipe shall be tested.
  • For material heat treated by the continuous process, tests shall be made on a sufficient number of pipe to constitute 5% of the lot, but in no case less than 2 pipe.
Notes for Bend Test:
  • For pipe whose diameter exceeds NPS 25 and whose diameter to wall thickness ratio is 7.0 or less shall be subjected to the bend test instead of the flattening test.
  • Other pipe whose diameter equals or exceeds NPS 10 may be given the bend test in place of the flattening test subject to the approval of the purchaser.
  • The bend test specimens shall be bent at room temperature through 180 without cracking on the outside of the bent portion.

Advantages of P91

SA 335 P91 or SA 213 T91 is the ultimate Ferrite Alloy steel that meets the extensive condition. Normally, the materials are used in many numbers of successful power plant service. Metal is also called as the 9 Cr 1 Mo steel with more composition. T22 or P22 grade is its predecessor but the Grade 91 mainly exhibits with the higher strength of temperature in the range of about 600 °C. Oxidation temperature mainly limits to higher features so it also effectively allows power plant designers to extensively engineer the components. In fact, it also effectively allows power plant designers for easily engineering the components with superheater coils, steam piping and headers as it mainly has less thickness. The metal also contributes higher thermal fatigue life that is ten times stronger when compared to other metals in much excellence. It also effectively allows to increase operating temperature at the higher level and increased efficiency at the power plant.

Normally, Alloy steel is not tolerant based on variations in the microstructure when compared to the P22 grade and other grades. Alloy steel is available in the difference that mainly contains the amount of carbon and iron. These are like the carbon steel along with it has other elements. Elements used in the Alloy steel mainly add manganese, silicon, chromium, vanadium, boron, and nickel. With more number of value composition about elements that are presented based on different ranges with more properties in the alloy steel. Normally, usage or application of alloy steel is to acquire the well-determined physical properties of the steel. The alloy steel falls into 2 types that include low alloy steels and high alloy steels. The Alloy steel is considered as the high alloy properties with the amount of the included elements belongs to the level of 8%. When these elements are combined with the range that is perforated in the below 8% value then it is called as low alloy steel. Low alloy steel is only used in most of the factories.

Alloy Steel P91 is manufactured based on precision and strict industry standard that mainly follows the heat treatment requirements. It is also reported that the failures of base materials are completely based on the different stages of usage. Alloy Steel P91 mainly used for different application with the extensive precision manufactured that are also complete reinstate with the microstructure to the high excellence. Alloy Steel P91 has properties much lower when compared to the predecessor P22. The effect of variation based on treatment on properties would be quite easier to analyze but it is not in the suitable for P91. Fabrication with construction phase mainly affects microstructure with reversed by precise heat treatment. In fact, it also brings microstructure back to original size and shape to the excellence. Alloy Steel P91 is decided based on tanker linings with complete prevalent consumption protection with high return quality and it also efficiently adds structures. With the variety of welding consumables along other national specifications enabled, P91 materials are widely used across for different aspects.

ASTM A335 P91 pipe Stocks

ASTM A335 P91 is the part of ASTM A335, The pipe shall be suitable for bending, flanging, and similar forming operations, and for fusion welding. The steel material shall conform to chemical composition, tensile property, and hardness requirements.

The range of ASTM A335 P91 pipe sizes that may be examined by each method shall be subjected to the limitations in the scope of the respective practice.

astm a335 p91 alloy pipe 02 astm a335 p91 alloy pipe 03 astm a335 p91 alloy pipe 04 astm a335 p91 alloy pipe 05 astm a335 p91 alloy pipe 06 astm a335 p91 alloy pipe 07 astm a335 p91 alloy pipe 08

Process

Cold drawn seamless steel tube deformed process

Cold Drawn Seamless Mechanical Tubing (CDS) is a cold drawn 1018/1026 steel tube which offers uniform tolerances, enhanced machinability and increased strength and tolerances compared to hot-rolled products.

Cold drawn seamless steel tubes process

Cold drawn steel tube is with hot-rolled steel coil as raw material, and tandem cold rolling pickled to remove oxide scale, its finished rolling hard roll, rolling hard volumes due to the continuous cold deformation caused by cold hardening strength, hardness increased indicators declined tough plastic, stamping performance will deteriorate, which can only be used for simple deformation of the parts.

Rolling hard roll can be used as the raw material of the hot-dip galvanizing plant, hot dip galvanizing line set annealing line. Rolling hard roll weight is generally 6 to 13.5 tons, the coil diameter of 610mm.


Hot rolled seamless steel pipe deformed process

Hot-rolled seamless steel pipe production base deformation process can be summarized as three stages: perforation, extension and finishing.

Hot rolled seamless steel pipe deformed process

The main purpose of the perforation process is to become a solid round billet piercing hollow shell. Capillary in the specifications, accuracy and surface quality can not meet the requirements of the finished product, further improvements are needed to deform the metal through. The main purpose of the stretching machine is further reduced sectional view (main compression wall) for a larger axial extension, so that the capillary improved dimensional accuracy, surface quality and organizational performance.

After stretching machine rolled steel pipe shortage collectively need further molding mill in order to achieve the requirements of the finished pipe. Rolled steel due to pass in the method widely used in the production of seamless steel tubes.

So far, due to the method pass rolling steel can be divided into two categories: core pension without rolling rolling (hollow body rolling), and with the mandrel. Sizing machines, reducing mill and stretch reducing mill belonging to the hole without mandrel type continuous rolling mills are generally coffin. Its main purpose is to reduce the diameter of the deformation process or sizing get finished steel, the wall thickness of process control, can make thinning, thickening or nearly unchanged.

All the traditional hole-type rolling machine with mandrel belong to extend machine. The main purpose is to reduce the deformation process perforated capillary wall thickness and outer diameter roll passes in the deformation zone and the mandrel posed, for a larger axial extension. At the same time a certain improvement in the organization, performance, accuracy, surface quality.


Cut to LengthASTM A210 seamless medium carbon steel boiler and superheater tubes

Before cutting pipe and tubing

No matter the material, measure the diameter of the pipe or tube to be cut to ensure that you use the right-size tube cutter for the job. When determining how to make a straight cut, use a tape measure and a pencil or other writing instrument to mark on the surface where you want to cut. If possible, mark around the circumference of a pipe, especially when cutting with a handsaw. Ensure that a cut is as straight as possible by securing the pipe with a vise, clamp, miter box or even duct tape to keep the length from shifting out of place while cutting.

After cutting pipe and tubing

  • Unless a cut is perfectly clean, you should expect to remove burrs from around the edge, especially after sawing.
  • Use a deburring tool to clean the edge after tube cutting.
  • You may opt to use a metal file on the cut of a metal pipe.

Inspection

Inspection and test of alloy steel pipe:
Chemical composition inspection, mechanical properties test(tensile strength,yield strength, elongation, flaring, flattening, bending, hardness, impact test), surface and dimension test,no-destructive test, hydrostatic test.

PMI


Size measurement

Delivery

Bare packing/bundle packing/crate packing/wooden protection at the both sides of tubes and suitably protected for sea-worthly delivery or as requested.

Placing steel pipes into containers


Application

Alloy steel pipes are ideally suitable for chemical, petrochemicals, and other energy-related applications.

The alloy steel pipe adopts high quality carbon steel, alloy structural steel and stainless & heat resisting steel as raw material through hot rolling or cold drawn to be made.

Alloy steel can be used in process area where carbon steel has limitation such as

  • High-temperature services such as heater tubes
  • Low-temperature services such as cryogenic application
  • Very high presser service such as steam header

As an important element of steel products, alloy steel pipe can be divided into seamless steel pipe and welded steel pipe according to the manufacturing technique and tube billet shape.

Here you can see the common alloy steel grade that you will come across.

  • For Pipes: ASTM A335 Gr P1, P5, P11, P9
  • For Wrought Fittings: ASTM A234 Gr.WP5, WP9, WP11
  • For Forged Fittings: ASTM A182 F5, F9, F11 etc.

Why the application of alloy steel pipe is wider than others

There are many kinds of materials used for transport in industrial production. Specifically we will have more choices and it is not limited to the use of alloy steel pipe. But even in the face of more choices, many people tend to choose alloy steel pipe. People make their own choices will have their own reasons. This means the alloy steel pipe application has its own advantages. Compared with transmission lines made of other materials, after it meets the basic application requirements, its quantity is lighter. Then in the practical application of alloy steel pipe, it will have more advantages because of this. Besides its physical characteristic advantage, it also has economic advantages. The wide application of alloy steel pipe is with kinds of reasons. So in practical usage, we can exploit the advantages to the full, in this way can we get more profits in these applications of alloy steel pipe.

What requirements should alloy steel pipe application meet

The transportation of kinds of gases or liquids in production needs to rely on alloy steel pipe. This shows that the actual role of alloy steel pipe application is important. High temperature resistant and low temperature resistant is the tolerance of temperature. In the practical application of alloy steel pipe, there will be many materials need to be transported. However their temperatures are not the same. So this can be the basic requirement to alloy steel pipe. It needs more corrosion resistance. Corrosion resistant material is the best material during transporting, because it is corrosion resistant. So it can be used in more occasions. And it is definitely very convenient for users.

The biggest advantages of alloy steel pipe

Can be 100% recycled, environmentally friendly, energy-saving, resource conservation, national strategy, national policy to encourage the expansion of the field of application of high-pressure alloy pipe. Of alloy steel pipe total consumption accounted steel in the proportion is only half of the developed countries, to expand the field of use of the alloy steel pipe to provide a wider space for the development of the industry. The future needs of the average annual growth of China’s high-pressure alloy steel pipe long products up to 10-12%.

Specification, standard and identification of alloy steel pipes

Alloy Steel pipe contains substantial quantities of elements other than carbon such as nickel, chromium, silicon, manganese, tungsten, molybdenum, vanadium and limited amounts of other commonly accepted elements such as manganese, sulfur, silicon, and phosphorous.

Industries We Serve

Our team of experienced sales specialists proudly partners with gas and chemical processors, power generation plants, oil refineries, and related industries to offer piping components and value-added services.

The biggest advantages of alloy steel pipe can be 100% recycled, environmentally friendly, energy-saving, resource conservation, national strategy, national policy to encourage the expansion of the field of application of high-pressure alloy pipe. Of alloy tube total consumption accounted steel in the proportion is only half of the developed countries, to expand the field of use of the alloy tube to provide a wider space for the development of the industry. According to the Chinese Special Steel Association alloy pipe Branch Expert Group, the future needs of the average annual growth of China’s high-pressure alloy pipe long products up to 10-12%.

Q&A

Our team of experienced sales specialists proudly partners with gas and chemical processors, power generation plants, oil refineries, and related industries to offer piping components and value-added services.

Alloying Elements

Alloying ElementsEffect on the Properties
ChromiumIncreases Resistance to corrosion   and oxidation. Increases hardenability and wear resistance. Increases high   temperature strength.
NickelIncreases hardenability. Improves   toughness. Increases impact strength at low temperatures.
MolybdenumIncreases hardenability, high   temperature hardness, and wear resistance. Enhances the effects of other   alloying elements. Eliminate temper brittleness in steels. Increases high   temperature strength.
ManganeseIncreases hardenability. Combines   with sulfur to reduce its adverse effects.
VanadiumIncreases hardenability, high   temperature hardness, and wear resistance. Improves fatigue resistance.
TitaniumStrongest carbide former. Added to   stainless steel to prevent precipitation of chromium carbide.
SiliconRemoves oxygen in steel making.   Improves toughness. Increases hardness ability
BoronIncreases hardenability. Produces   fine grain size.
AluminumForms nitride in nitriding steels.   Produces fine grain size in casting. Removes oxygen in steel melting.
CobaltIncreases heat and wear   resistance.
TungstenIncreases hardness at elevated   temperatures. Refines grain size.
Commonly used alloying elements and their effects are listed in the table given below.

The most important and desired changes in alloy steel are

Alloy steels are made by combining carbon steel with one or several alloying elements, such as manganese, silicon, nickel, titanium, copper, chromium and aluminum. These metals are added to produce specific properties that are not found in regular carbon steel. The elements are added in varying proportions (or combinations) making the material take on different aspects such as increased hardness, increased corrosion resistance, increased strength, improved formability (ductility); the weldability can also change.

  • Increased hardenability.
  • Increased corrosion resistance.
  • Retention of hardness and strength.
  • Nearly all alloy steels require heat treatment in order to bring out their best properties.

Alloying Elements & Their Effects

  • Chromium – Adds hardness. Increased toughness and wear resistance.
  • Cobalt – Used in making cutting tools; improved Hot Hardness (or Red Hardness).
  • Manganese – Increases surface hardness. Improves resistance to strain, hammering & shocks.
  • Molybdenum – Increases strength. Improves resistance to shock and heat.
  • Nickel – Increases strength & toughness. Improves corrosion resistance.
  • Tungsten – Adds hardness and improves grain structure. Provides improved heat resistance.
  • Vanadium – Increases strength, toughness and shock resistance. Improved corrosion resistance.
  • Chromium-Vanadium – Greatly improved tensile strength. It is hard but easy to bend and cut.

Pipes, Tubes and Hollow Sections

Norms:

  • API 5L – Line Pipe
  • ASTM A 53 – Black and Hot-Dipped, Zinc-Coated, Welded and Seamless, Steel Pipe
  • ASTM A 106 – Seamless Carbon Steel Pipe for High-Temperature Service
  • ASTM A 213 – Seamless Ferritic and Austenitic Alloy-Steel Boiler, Superheater, and Heat-Exchanger Tubes
  • ASTM A 269 – Seamless and Welded Austenitic Stainless Steel Tubing for General Service
  • ASTM A 312 – Seamless, Welded, and Heavily Cold Worked Austenitic Stainless Steel Pipes
  • ASTM A 333 – Seamless and Welded Steel Pipe for Low-Temperature Service
  • ASTM A 335 – Seamless Ferritic Alloy-Steel Pipe for High-Temperature Service
  • ASTM A 358 – Electric-Fusion-Welded Austenitic Chromium-Nickel Stainless Steel Pipe for High-Temperature Service and General Applications
  • ASTM A 671 – Electric-Fusion-Welded Steel Pipe for Atmospheric and Lower Temperatures
  • ASTM A 672 – Electric-Fusion-Welded Steel Pipe for High-Pressure Service at Moderate Temperatures
  • ASTM A 790 – Seamless and Welded Ferritic/Austenitic Stainless Steel Pipe
  • ASTM A 928 – Ferritic/Austenitic (Duplex) Stainless Steel Pipe Electric Fusion Welded with Addition of Filler Metal
  • EN 10208-2 – Steel pipes for pipelines for combustible fluids – Part 2: Pipes of requirement class B
  • EN 10210-1/2 – Hot finished structural hollow sections of non-alloy and fine grain steels
  • EN 10216-1 – Seamless steel tubes for pressure purposes – Part 1: Non-alloy steel tubes with specified room temperature properties
  • EN 10216-2 – Seamless steel tubes for pressure purposes – Part 2: Non-alloy and alloy steel tubes with specified elevated temperature properties
  • EN 10217-1 – Welded steel tubes for pressure purposes – Part 1: Non-alloy steel tubes with specified room temperature properties
  • EN 10217-2 – Welded steel tubes for pressure purposes – Part 2: Electric welded non-alloy and alloy steel tubes with specified elevated temperature properties
  • EN 10219-1/2 – Cold formed welded structural hollow sections of non-alloy and fine grain steels
  • EN 10297-1 – Seamless circular steel tubes for mechanical and general engineering purposes – Part 1 Non-alloy and alloy steel tubes

Grade:

  • API 5L Gr. A, B, X42, X52, X60, X65, X70
  • ASTM A 53 Gr. A, Gr. B
  • ASTM A106 Gr. A, B, C
  • ASTM A 213 TP 304, 304L, 304H, 316, 316L, 316H, 321, 321H, T5, T9, T11
  • ASTM A 269 TP 304, 304L, 304H, 316, 316L, 316H, 321, 321H
  • ASTM A 312 TP 304, 304L, 304H, 316, 316L, 316H, 321, 321H
  • ASTM A 333 Gr. 3, Gr. 6 ASTM A 335 P1, P2, P5, P9, P11, P12, P22, P91, P92
  • ASTM A 358 TP 304, 304L, 304H, 316, 316L, 316H, 321, 321H
  • ASTM A 671 CC 60, CC 65, CC 70
  • ASTM A 672 CC 60, CC 65, CC 70
  • ASTM 790 UNS S31803, UNS S32205, UNS S32750, UNS S32760
  • ASTM A928
  • EN 10208-2 L245, L 290, L360
  • EN 10210-1 S235 JRH, S275 JOH, S275 J2H, S355 JOH, S355 J2H
  • EN 10216-1 P235 TR1/2
  • EN 10216-2 P235 GH, P265 GH
  • EN 10217-1 P235 TR1/2, P275 TR1/2
  • EN 10217-2 P235 GH, P265 GH
  • EN 10219-1 S235 JRH, S275 JOH, S275 J2H, S355 JOH, S355 J2H
  • EN 10297-1 E235, E275, E315, E355, E470

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FAQ

Q: How long is your delivery time?
A: The delivery time of customized products is generally 25 35 days, and non customized products are generally shipped within 24 hours after payment.

Q: Do you provide samples? Is it free?
A: If the value of the sample is low, we will provide it for free, but the freight needs to be paid by the customer. But for some high value samples, we need to charge a fee.

Q: What are your payment terms?
A: T/T 30% as the deposit,The balance payment is paid in full before shipment

Q: What is the packaging and transportation form?
A: Non steaming wooden box and iron frame packaging. Special packaging is available according to customer needs. The transportation is mainly by sea.

Q: What is your minimum order quantity?
A: There is no minimum order quantity requirement. Customized products are tailor made according to the drawings provided by the customer.