APPLICATIONHollow Bars are both hollow bars and seamless tubes. Hollow Bars are manufactured specifically for production of radially machined components. Hollow bars are used in production of valves and actuators (flowmeters, valves, filters, manifolds); pumps and compressor (vacuum equipment, hydraulic cylinders, pump housings); axes and shafts (rolls, guides, bushings, clamps, bearings); mechanical gaskets (seals, spacers, rings); connection components (fittings, flanges, couplings, connectors); measuring instruments (sensors, solenoids, resistors).
All of the abovementioned products can be used in various industries, as general machinery, chemical and petrochemical industry, shipbuilding industry, automotive industry, paper and paperboard industry, textile industry, food industry, etc. The use of hollow bars minimizes material losses and reduces overall need in processing completely excluding operation of equipment for deep drilling. Chemical composition of steels used for manufacturing of hollow bars provides higher speed of cutting and long lifetime of cutting tools ensuring a defect-free surface after machining.
BASIC SIZE RANGE AND STANDARDS
Stainless Europe offers a range of standard sizes listed in the table most demanded by machine-building companies and equipment manufacturers. Requirements to hollow bars are in accordance with EN 10216-5 and ASTM A312. On the Customer’s request, the company imports an additional range of sizes and grades not included in the standards as well as production of hollow bars in accordance with the requirements of NF A 49-317 is possible.
TYPICAL MATERIAL SAVINGS
The blue line represents the loss of material `Z` involved when turning a solid round into a Mechanical Tube. Here 45 % of the solid round must be removed for this purpose. The dotted line illustrates the tube length factor `D` which indicates the extra length available for the mechanical parts production as opposed to solid rounds of the same weight. The example shows a 1.8-fold tube length increase, which means that almost twice as many parts can be made from the tubular weight of material.
TOLERANCES
Under Hollow Bars production permissible variations in OD are plus tolerance, in ID are minus tolerance. Tolerance for production is a critical parameter when ordering products. For Hollow Bar, OD tolerance is within the plus range and ID tolerance – within the minus range. Allowable wall thickness deviation is defined by the degree of cross-sectional center displacement; this is due to the effect of allowable tolerance for outside and inside diameter, wall thickness and center displacement. In case of tubes for machining (acc. to ASTM A511), tolerances for outside and inside diameters and wall thickness usually are within plus and minus range of nominal size. Thus, differences in tolerances between Hollow Bar and ASTM A 511 should be taken into account when ordering products for further machining
STANDARD STEEL GRADES
Hollow bars and Mechanical tubing are supplied in a range of specially selected stainless and acid-resistant standard grades chosen to cover the majority of corrosion and processing problems that occur in daily practice.
Stainless Europe Sp. z o.o. is a supplier of metallurgical products made of stainless steel. He offers products such as: stainless steel pipes and hollow bars, elbows, tees, reducers, sheets, stainless round bars etc. Over twenty grades of austenitic, ferritic, martensitic and duplex steels. Stainless Europe has on stock also heat-resistant bars and pipes.
All these products are available in the stainlesseurope.com online shop. Customers can choose from over 15,000 products – also in small retail quantities with quick delivery to the indicated personal address or to a parcel locker.
