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Help Support Hardline Crawlers :
Help settle this Cold verses hrew question
- Thread starter kushKrawlin
- Start date
pholmann
Well-Known Member
Ok so this thread was only a thread about what was strongest and in what order correct? Why did it turn into a pissing contest about what the **** a chassis should be built out of? A chassis should be built out of what the person paying for it says it should. If you have the extra cash and want chromoly or dom go for it. If your on a budget then go for HREW. I'm hearing so many peoples opinions thrown out there as this is what EVERYONE should do. It's all a matter of opinion. It was settled on what order things were in terms of strength a couple of pages ago. The price also goes pretty much in the same order. Why is everyone beating this dead horse. Build your **** out of what you want and what you can afford and use it accordingly. The rest is all opinion and opinions are like assholes, everyone has one and everyone else's stinks!
machen4x4
Well-Known Member
1020 is normally used in the manufacturing of small-diameter or thin-wall DOM steel tube. DOM is formed from strip and electric-resistance welded, then cold drawn to size. The cold drawing process causes the weld line to virtually disappear.
Typical Mechanical Properties: Tensile strength (ksi) 80
1018 is normally used in the manufacturing of cold drawn and hot finished seamless tube. The production of seamless tube is generally made by piercing a hot rolled bar. Hot finished is generally furnished in the unannealed condition, whereas cold drawn seamless is supplied in the unannealed or S/R annealed conditions, depending on the size.
Tensile strength (ksi) 60
1010 is normally used in the manufacturing of electric-resistance welded tube. The product is available normally in cold rolled strip (16 gauge and lighter), and hot rolled strip (.083" wall and heavier). The product can be obtained in the as-welded condition (flash-in) or in the flash-controlled condition.
Typical Mechanical Properties: Tensile strength (ksi) 45
1026 grade is normally used in the manufacturing of DOM, cold drawn seamless and hot finished seamless. This grade normally furnished over 2" OD, with walls heavier than .156". A variety of thermal treatments can be supplied, depending on the type and size of material.
Tensile strength (ksi) 87
Contnuous (butt welded) pipe process.
The continuous process produces a full range of pipe sizes from only a few different widths of skelp. The coils of skelp, or strip, are fed into the mill and their ends welded together to provide a continuous flow. The strip passes through a pre-heater and into a furnace. The heated strip is shaped into an arc of about 270° in a forming stand before passing into the welding stand. There a nozzle applies oxygen to the edges to further heat them as they are pressed and welded together. The pipe's OD and wall thickness are reduced in a stretch-reducing mill. Pipe is then cut to length, reduced to the required size in a sizing mill and water-cooled before being straightened. It is then ready for finishing
Typical Electric Resistance Welded tube process
Steel strip is unwound from coils and side-trimmed to control width and condition the edges for welding. The strip then passes through a series of contoured rolls which progressively cold-form it into a circular shape. The edges are forced together under pressure and welded by heating the steel to temperatures between 2200° F and 2600° F using copper contacts or coil induction. Weld flash is removed from the the inside and outside surfaces of the newly-formed pipe, and the weld zone is heat treated to ensure homogeneity between the base metal and weld. The weld is subjected to in-line nondestructive testing, and the tube then passes through a series of sizing rolls to attain its precise finished diameter. It is then straightened and cut to the desired finished length.
DOM tube being constructed, starting as ERW and then being drawn over a mandrel.
The manufacturing process for DOM tubing begins with coils of steel, which are slit to the proper width for the desired tube size. The strip is cold formed and passed through an electric resistance welder which joins the edges together, under pressure, to complete the tubular shape. After testing the weld's integrity, the tubing is cut to length for further processing
Seamless tube construction
The production process for seamless tube begins by heating a steel billet to about 2250° F. The red-hot billet is rotated and drawn by rolls over a piercing rod, or mandrel. The action of the rolls causes the metal to flow over and about the mandrel to create a hollow tube shell. After reheating, the shell is moved forward over a support bar and is hot-rolled in several reducing/sizing stands to the desired wall thickness and diameter. The tube, which has grown significantly in length during the piercing and sizing processes, is then cut into sections and conveyed across a cooling bed to cool slowly in the air. It then receives whatever finishing processes are needed to meet customer requirements.
Steel tubing is usually supplied in one of the following forms:
Seamless Tube.
This is expensive and specialized stuff. It IS NOT the commonly used (and misreferenced) DOM tubing, as DOM tubing does indeed have a seam (albeit, almost invisible - more details below). True seamless tubing is uncommon in 4x4 and automotive use. It is seamless because it is manufactured by a process know as "extrusion" where a solid bar of steel is pierced down the center with a die, at unthinkable pressures, to form a tube. The process looks similar to how hollow pasta (macaroni etc) is made. There are 2 sub-types of seamless tube:
Cold Drawn Seamless (CDS) Tube is normally drawn to O.D. and I.D. dimensions and produced to standard dimensional tolerances (this differs from most other types of tubing except DOM) . It is normally made from SAE 1018 and is considered good quality.
Hot Finished Seamless (HFS) Tube is lower in cost than cold drawn and most applicable where precise dimensions and surface quality are of secondary importance. It is manufactured to O.D. and wall dimensions from SAE 1026 steel and is scaly, less dependable and not as strong as cold drawn tube.
Electric Resistance Welded (ERW) Tube
ERW is the most economical and readily available type of mechanical tuning. It is produced by taking a flat bar of steel and rolling it into a tube shape (picture rolling up a newspaper - but without any overlap) and then welding the seam - by, you guessed it - electric resistance - hence the name. Electric resistance welding is somewhat like a long, continuous spot weld. It's often computer controlled and extremely consistent. ERW is normally SAE 1010 (for wall thickness < 16 ga) or SAE 1020. ERW tube comes in 2 flavours:
Hot Rolled ERW (HREW)
HREW is rolled into a tube at elevated temperatures, usually way above room temperature. This produces a tubing that is more malleable and therefore easier to form but that is also not as strong, is supplied covered with scale, and not as uniform in dimension as cold rolled. It is also quite a bit cheaper than cold rolled.
Cold Rolled ERW (CREW)
CREW is manufactured by a process in which a steel bar is rolled into a tube and the seam welded, usually at room temperature. Compared to hot rolled, CREW is stronger - (greater yield strength) - because of the improvement in the crystal lattice structure from improved grain size, shape, and orientation imparted by being worked at cold (room) temperatures), straighter, has a much smoother and more uniform surface finish, and is made to much tighter, more consistent dimensions. It is the best economical choice for tube work, and because of the better surface finish and tighter dimensional tolerances it is much nicer to work with than HREW.
Drawn Over Mandrel (DOM)
Strong and well-finished DOM is an electric resistance welded tube tested for soundness of weld and drawn through a die and over a mandrel. This process imparts significantly improved mechanical properties to the tube, due to the cold working process. It is considered a high quality tube, and is normally constructed from SAE 1020 or 1026 steel. Note that, technically DOM refers to the process by which the tube is finished after having started as an ERW tube. Technically, DOM is not a type of steel tube, but rather a process. As so often happen though - in common use the term has become accepted to mean a specific type of tubing rather than a process. In this case, when people say "DOM" they normally mean an ERW tube drawn over a mandrel at (close to) room temperature and made from SAE 1020 steel. It is normally drawn to O.D. and I.D. dimensions. Here is what the Steel Tube Institute of North America has to say about DOM:
The DOM Manufacturing Process
The manufacturing process for DOM tubing begins with coils of steel, which are slit to the proper width for the desired tube size. The strip is cold formed and passed through an electric resistance welder which joins the edges together, under pressure, to complete the tubular shape. After testing the weld's integrity, the tubing is cut to length for further processing.
The cold-drawing process creates a uniform, precision product with substantially improved tolerances, surface finish and tensile strength, increased hardness and good machinability. In this process, the tube is cleaned and annealed, and one end of each length is squeezed to a point so it can be gripped by the drawing mechanism. The tube is then drawn through one or more dies and over mandrels. This reduces the diameter of the tube and thins its walls to the required dimensions in a controlled fashion to provide the qualities desired in the finished product. Metallurgically, drawing improves the tube's concentricity, tensile strength, hardness and machinability. Close dimensional accuracy is achieved through tight control of both outside and inside diameters.
Typical Mechanical Properties: Tensile strength (ksi) 80
1018 is normally used in the manufacturing of cold drawn and hot finished seamless tube. The production of seamless tube is generally made by piercing a hot rolled bar. Hot finished is generally furnished in the unannealed condition, whereas cold drawn seamless is supplied in the unannealed or S/R annealed conditions, depending on the size.
Tensile strength (ksi) 60
1010 is normally used in the manufacturing of electric-resistance welded tube. The product is available normally in cold rolled strip (16 gauge and lighter), and hot rolled strip (.083" wall and heavier). The product can be obtained in the as-welded condition (flash-in) or in the flash-controlled condition.
Typical Mechanical Properties: Tensile strength (ksi) 45
1026 grade is normally used in the manufacturing of DOM, cold drawn seamless and hot finished seamless. This grade normally furnished over 2" OD, with walls heavier than .156". A variety of thermal treatments can be supplied, depending on the type and size of material.
Tensile strength (ksi) 87
Contnuous (butt welded) pipe process.
The continuous process produces a full range of pipe sizes from only a few different widths of skelp. The coils of skelp, or strip, are fed into the mill and their ends welded together to provide a continuous flow. The strip passes through a pre-heater and into a furnace. The heated strip is shaped into an arc of about 270° in a forming stand before passing into the welding stand. There a nozzle applies oxygen to the edges to further heat them as they are pressed and welded together. The pipe's OD and wall thickness are reduced in a stretch-reducing mill. Pipe is then cut to length, reduced to the required size in a sizing mill and water-cooled before being straightened. It is then ready for finishing
Typical Electric Resistance Welded tube process
Steel strip is unwound from coils and side-trimmed to control width and condition the edges for welding. The strip then passes through a series of contoured rolls which progressively cold-form it into a circular shape. The edges are forced together under pressure and welded by heating the steel to temperatures between 2200° F and 2600° F using copper contacts or coil induction. Weld flash is removed from the the inside and outside surfaces of the newly-formed pipe, and the weld zone is heat treated to ensure homogeneity between the base metal and weld. The weld is subjected to in-line nondestructive testing, and the tube then passes through a series of sizing rolls to attain its precise finished diameter. It is then straightened and cut to the desired finished length.
DOM tube being constructed, starting as ERW and then being drawn over a mandrel.
The manufacturing process for DOM tubing begins with coils of steel, which are slit to the proper width for the desired tube size. The strip is cold formed and passed through an electric resistance welder which joins the edges together, under pressure, to complete the tubular shape. After testing the weld's integrity, the tubing is cut to length for further processing
Seamless tube construction
The production process for seamless tube begins by heating a steel billet to about 2250° F. The red-hot billet is rotated and drawn by rolls over a piercing rod, or mandrel. The action of the rolls causes the metal to flow over and about the mandrel to create a hollow tube shell. After reheating, the shell is moved forward over a support bar and is hot-rolled in several reducing/sizing stands to the desired wall thickness and diameter. The tube, which has grown significantly in length during the piercing and sizing processes, is then cut into sections and conveyed across a cooling bed to cool slowly in the air. It then receives whatever finishing processes are needed to meet customer requirements.
Steel tubing is usually supplied in one of the following forms:
Seamless Tube.
This is expensive and specialized stuff. It IS NOT the commonly used (and misreferenced) DOM tubing, as DOM tubing does indeed have a seam (albeit, almost invisible - more details below). True seamless tubing is uncommon in 4x4 and automotive use. It is seamless because it is manufactured by a process know as "extrusion" where a solid bar of steel is pierced down the center with a die, at unthinkable pressures, to form a tube. The process looks similar to how hollow pasta (macaroni etc) is made. There are 2 sub-types of seamless tube:
Cold Drawn Seamless (CDS) Tube is normally drawn to O.D. and I.D. dimensions and produced to standard dimensional tolerances (this differs from most other types of tubing except DOM) . It is normally made from SAE 1018 and is considered good quality.
Hot Finished Seamless (HFS) Tube is lower in cost than cold drawn and most applicable where precise dimensions and surface quality are of secondary importance. It is manufactured to O.D. and wall dimensions from SAE 1026 steel and is scaly, less dependable and not as strong as cold drawn tube.
Electric Resistance Welded (ERW) Tube
ERW is the most economical and readily available type of mechanical tuning. It is produced by taking a flat bar of steel and rolling it into a tube shape (picture rolling up a newspaper - but without any overlap) and then welding the seam - by, you guessed it - electric resistance - hence the name. Electric resistance welding is somewhat like a long, continuous spot weld. It's often computer controlled and extremely consistent. ERW is normally SAE 1010 (for wall thickness < 16 ga) or SAE 1020. ERW tube comes in 2 flavours:
Hot Rolled ERW (HREW)
HREW is rolled into a tube at elevated temperatures, usually way above room temperature. This produces a tubing that is more malleable and therefore easier to form but that is also not as strong, is supplied covered with scale, and not as uniform in dimension as cold rolled. It is also quite a bit cheaper than cold rolled.
Cold Rolled ERW (CREW)
CREW is manufactured by a process in which a steel bar is rolled into a tube and the seam welded, usually at room temperature. Compared to hot rolled, CREW is stronger - (greater yield strength) - because of the improvement in the crystal lattice structure from improved grain size, shape, and orientation imparted by being worked at cold (room) temperatures), straighter, has a much smoother and more uniform surface finish, and is made to much tighter, more consistent dimensions. It is the best economical choice for tube work, and because of the better surface finish and tighter dimensional tolerances it is much nicer to work with than HREW.
Drawn Over Mandrel (DOM)
Strong and well-finished DOM is an electric resistance welded tube tested for soundness of weld and drawn through a die and over a mandrel. This process imparts significantly improved mechanical properties to the tube, due to the cold working process. It is considered a high quality tube, and is normally constructed from SAE 1020 or 1026 steel. Note that, technically DOM refers to the process by which the tube is finished after having started as an ERW tube. Technically, DOM is not a type of steel tube, but rather a process. As so often happen though - in common use the term has become accepted to mean a specific type of tubing rather than a process. In this case, when people say "DOM" they normally mean an ERW tube drawn over a mandrel at (close to) room temperature and made from SAE 1020 steel. It is normally drawn to O.D. and I.D. dimensions. Here is what the Steel Tube Institute of North America has to say about DOM:
The DOM Manufacturing Process
The manufacturing process for DOM tubing begins with coils of steel, which are slit to the proper width for the desired tube size. The strip is cold formed and passed through an electric resistance welder which joins the edges together, under pressure, to complete the tubular shape. After testing the weld's integrity, the tubing is cut to length for further processing.
The cold-drawing process creates a uniform, precision product with substantially improved tolerances, surface finish and tensile strength, increased hardness and good machinability. In this process, the tube is cleaned and annealed, and one end of each length is squeezed to a point so it can be gripped by the drawing mechanism. The tube is then drawn through one or more dies and over mandrels. This reduces the diameter of the tube and thins its walls to the required dimensions in a controlled fashion to provide the qualities desired in the finished product. Metallurgically, drawing improves the tube's concentricity, tensile strength, hardness and machinability. Close dimensional accuracy is achieved through tight control of both outside and inside diameters.
kushKrawlin
Well-Known Member
Well put.. . The only reason i started this thread was to find out why i never see chassis made out of CREW and MOST of the time its HREW, i had no clue that this is a subject that has apparently been discussed and bickered about many times, :****: i just really appreciate the info, i learn alot from you guys on here. So when The guy at the metal shop asked why not use CREW on a roll cage , and it through me off, i tried to look it up but after a tryin to get through a couple pirate threads i fukin gave up and asked here, where i knew i could get good info.. Thanks again fellas.pholmann said:
bgredjeep
Well-Known Member
- Joined
- Jul 1, 2011
- Messages
- 719
AdamF said:
That drag race example is nice, but I'd like to think my cage in the Jeep won't be a one time use item.
For chromoly, it's not just the material (something like $8+/FT last I checked), but also the process required to properly build with it that makes it cost prohibitive. TIG welding and heat treating a chassis is $$$ if it's done by someone who's worth doing it. If you don't TIG and heat treat, then you wasted your money on the tube in the first place.
Re: Help settle this Cold verses hrew question
It's important Kush. What some folks see as incomplete info can be as bad as wrong info. This thread shows the "differing" opinions on the subject!
If the discussion of the two rew tubing was seen by someone, they might think those were the only two to consider.
It's important Kush. What some folks see as incomplete info can be as bad as wrong info. This thread shows the "differing" opinions on the subject!
If the discussion of the two rew tubing was seen by someone, they might think those were the only two to consider.
infamous1
Well-Known Member
Re:
Machen4x4 thanks for posting that, it answers alot of the questions I had but didn't want to feel stupid asking.
Sent from my Z750C using Tapatalk
Machen4x4 thanks for posting that, it answers alot of the questions I had but didn't want to feel stupid asking.
Sent from my Z750C using Tapatalk
crawlin85cj
Barco Motorsports
Re: Help settle this Cold verses hrew question
After having several trail rigs a couple race cars and literally beating them all within an inch of their life I can say from experience there is a hell of a lot more to building a chassis than material type. Strategic location of filler tubes plays a huge part in longevity.
1.75 x .120 DOM will dent and bend easier than expected unless supported properly. HREW tubing even more so. I've now had 3 buggies with .250 wall subframes and .188 wall overheads. All are supported in key locations and they maintain integrity after being put through a wrestling match with rocks at the mercy of my size 9 Nike. I destroyed the roof line and subframe of my first U4 car in under a year because it wasn't supported right and it took the lesser of the ass whipping. I had to align the axles every time out because things moved around in the subframe constantly. I swore I would do everything to never do that again. WFO is proof that a properly supported chassis with good material will deliver results. After 15 months I threw a tape on it and the axles are still aligned just as they were when it rolled out of WOD.
My current U4 car has been beat on now by 2 of us and everything is still right where it should be. WFO has been relentlessly beat by me and as a rental with nothing out if place. I would be willing to bet an experienced chassis builder could easily start with a mix of .250 wall, .120 wall and .095 wall HREW and build a solid chassis that would last years for the vast majority of owners.
My question is why? 1020 DOM tube is a better material and in the grand scheme of things the cost isn't that much more. The integrity of the chassis forms the foundation of a buggy and is key to a solid end result unless cosmetics are the only concern.
Just my opinion and experience. I have had bad results with both, mainly from inferior design work. Expensive lessons bring solid results later! My next car will be chromoly for added insurance.
2010 Jim' Garage U4 car
2013 Wide Open Design WFO
Looking for a JK!!!!
After having several trail rigs a couple race cars and literally beating them all within an inch of their life I can say from experience there is a hell of a lot more to building a chassis than material type. Strategic location of filler tubes plays a huge part in longevity.
1.75 x .120 DOM will dent and bend easier than expected unless supported properly. HREW tubing even more so. I've now had 3 buggies with .250 wall subframes and .188 wall overheads. All are supported in key locations and they maintain integrity after being put through a wrestling match with rocks at the mercy of my size 9 Nike. I destroyed the roof line and subframe of my first U4 car in under a year because it wasn't supported right and it took the lesser of the ass whipping. I had to align the axles every time out because things moved around in the subframe constantly. I swore I would do everything to never do that again. WFO is proof that a properly supported chassis with good material will deliver results. After 15 months I threw a tape on it and the axles are still aligned just as they were when it rolled out of WOD.
My current U4 car has been beat on now by 2 of us and everything is still right where it should be. WFO has been relentlessly beat by me and as a rental with nothing out if place. I would be willing to bet an experienced chassis builder could easily start with a mix of .250 wall, .120 wall and .095 wall HREW and build a solid chassis that would last years for the vast majority of owners.
My question is why? 1020 DOM tube is a better material and in the grand scheme of things the cost isn't that much more. The integrity of the chassis forms the foundation of a buggy and is key to a solid end result unless cosmetics are the only concern.
Just my opinion and experience. I have had bad results with both, mainly from inferior design work. Expensive lessons bring solid results later! My next car will be chromoly for added insurance.
2010 Jim' Garage U4 car
2013 Wide Open Design WFO
Looking for a JK!!!!
Neal3000
Well-Known Member
Was your first U4 car that white Jimmy's 4x4?
blacksheep10
XBJRA champ/ 555 and team Nasty codriver
I am going to say yes.Neal3000 said:
