Bright Bars

Cold finished stainless steel round bar, 5 mm to 115 mm, held to h7 through h11, k12 and k13

5 mm - 115 mm Up to 6.5 metres EN, DIN, JIS, ASTM, BS, ASME, GOST, AISI

OVERVIEW

Product Description

Stainless steel bright bar is hot rolled bar that has been cold finished at room temperature to a stated tolerance class and surface condition. Laxcon Steels draws, peels, turns and grinds round bright bar from 5 mm to 115 mm in lengths up to 6.5 metres, from steel melted and rolled in its own works. The bar is supplied to h7, h8, h9, h10, h11, k12 or k13, or to the ASTM A484 tolerance, with a surface finish of Ra 0.2 micron and straightness up to 0.5 mm per metre. AISI, EN, DIN and JIS are grade designation systems; ASTM A484 is the standard that sets the dimensional tolerance.

The finishing route sets the tolerance class and the price: centreless grinding holds h7 and h8, drawing and peeling hold h9 and h10, and a straightened, lightly finished bar holds h11 and the k classes. Bars are supplied as drawn or annealed after drawing, and the delivery condition on the test certificate names which applies. Eddy current testing is carried out where the order calls for it, positive material identification with a handheld spectrometer confirms the grade, and every bar is declared free of radioactive, mercury and lead contamination. Ends are chamfered at 30, 45 or 60 degrees or supplied plain.

Sizes above 115 mm are supplied as proof machined bar. The same finish in other sections is on the square bright bar, hexagonal bright bar and cold drawn flat bar pages, and bar held to a shaft fit and a straightness limit is precision shaft quality bar.

Grade chemistry, and the AISI, EN, DIN and JIS names for the same steel, are set out in the grade reference. Weight per metre by diameter is in the round bar weight chart, and the weight calculator works a bundle out from size, length and quantity.

Stainless steel bright bars produced by Laxcon Steels

SPECIFICATION

Bright Bars Supply Conditions

Size range: 5 mm - 115 mm (3/16" - 4-1/2")
Length: Up to 6.5 metres
Cold Drawn: Centreless Ground, Peeled & Polished, Rough Peeled or Smooth Turned Bars
Tolerances: h7, h8, h9, h10, h11, k12, k13, ASTM A484
Surface finish: Ra 0.2-micron (8.7 RMS)
Straightness: Up to 0.5 mm per metre
Grit polish: K240,K320 or as per customer’s requirement
Bars End Finish: Chamfered ends, 30°,45°,60° and Plain Ends without Burrs or Sharp Edges
Heat treatment: Soft Annealing, Solution Annealing, Oil & Water Quenching, Tempering & Aging
Specifications: as per EN, DIN, JIS, ASTM, BS, ASME, GOST, AISI (NACE MR0175, MR0103)

Eddy current tested as per customers requirement
Free from Radioactive elements, Mercury & Lead contamination
Grade confirmation through PMI testing with Handheld Spectrometers
Weight per metre for every listed size: metal weight calculator

Governing standards

EN 10088-3: Stainless steels: technical delivery conditions for semi-finished products, bars, rods, wire, sections and bright products for general purposes. Composition, heat treatment condition and mechanical properties per grade.
EN 10278: Dimensions and tolerances of bright steel products: the h and k tolerance classes for drawn, turned, peeled and ground bars.
ASTM A276/A276M: Stainless steel bars and shapes: composition, condition, mechanical properties and finish designations for hot-finished and cold-finished bar.
ASTM A484/A484M: General requirements for stainless steel bars, billets and forgings: permissible variations in dimensions, straightness, weight and length, and the test and marking requirements every bar order inherits.
ASTM A479/A479M: Stainless steel bars and shapes for use in boilers and other pressure vessels: the bar specification a pressure-part drawing calls for.
ISO 286-1 and 286-2: The ISO code system for tolerances on linear sizes: the IT grades and the fundamental deviations behind h7, h9, h11, k12, k13, j6, f7 and f8.
EN 10204: Metallic products, types of inspection documents: the 2.2 test report and the 3.1 and 3.2 inspection certificates a purchase order can call for.

Tolerance by size, ISO 286

Nominal diameter (mm)	h7	h8	h9	h10	h11	k12	k13
over 3 to 6	0 / -0.012	0 / -0.018	0 / -0.030	0 / -0.048	0 / -0.075	0 / +0.120	0 / +0.180
over 6 to 10	0 / -0.015	0 / -0.022	0 / -0.036	0 / -0.058	0 / -0.090	0 / +0.150	0 / +0.220
over 10 to 18	0 / -0.018	0 / -0.027	0 / -0.043	0 / -0.070	0 / -0.110	0 / +0.180	0 / +0.270
over 18 to 30	0 / -0.021	0 / -0.033	0 / -0.052	0 / -0.084	0 / -0.130	0 / +0.210	0 / +0.330
over 30 to 50	0 / -0.025	0 / -0.039	0 / -0.062	0 / -0.100	0 / -0.160	0 / +0.250	0 / +0.390
over 50 to 80	0 / -0.030	0 / -0.046	0 / -0.074	0 / -0.120	0 / -0.190	0 / +0.300	0 / +0.460
over 80 to 120	0 / -0.035	0 / -0.054	0 / -0.087	0 / -0.140	0 / -0.220	0 / +0.350	0 / +0.540

Deviations in millimetres from the nominal size, ISO 286-1 and ISO 286-2. An h class permits no plus material and the full grade below nominal; the k12 and k13 classes of EN 10278, used for peeled and turned bars, permit the full grade above nominal and none below.

Finishing route and tolerance class

Cold drawing pulls the annealed and pickled hot rolled bar through a die and holds h9 to h11 on diameter with a surface roughness of about 0.8 to 1.6 micron Ra. Peeling and smooth turning remove the rolled skin with a cutting tool and are supplied to the k12 and k13 classes of EN 10278, which put the whole tolerance above nominal so that a subsequent grinding pass still has material to remove. Centreless grinding holds h7 to h9 and brings the surface to 0.2 to 0.4 micron Ra; polishing to K240 or K320 grit follows grinding where a decorative or hygienic surface is specified.

Straightness is held to 0.5 mm per metre on the finished bar, measured as total indicator reading over the length. Ends are supplied plain, or chamfered at 30, 45 or 60 degrees, without burrs. A bar that will be further ground by the customer is ordered peeled to k12; a bar that goes straight into a machining centre is ordered drawn or ground to the h class the fit requires.

Weight per metre

Diameter (mm)	kg per metre	Metres per tonne
5	0.16	6,446.4
6	0.22	4,476.7
8	0.40	2,518.1
10	0.62	1,611.6
12	0.89	1,119.2
16	1.59	629.5
20	2.48	402.9
25	3.88	257.9
32	6.35	157.4
40	9.93	100.7
50	15.51	64.5
63	24.63	40.6
80	39.71	25.2
100	62.05	16.1
115	82.06	12.2

Density 7.90 g/cm³ (d² x 0.006205). A 304 bar at 7.93 g/cm³ runs 0.4 percent heavier, a 316 bar at 7.98 g/cm³ 1 percent heavier. Sizes are the published range at the nominal diameters shown.

Bright bar against hot rolled bar

A hot rolled round bar leaves the mill with the rolling skin on, to the tolerances of EN 10060 or ASTM A484, and is the lower-cost choice wherever the customer machines every surface in any case. A bright bar carries the same chemistry and heat number and adds a finishing pass that fixes the diameter to an ISO 286 class and the surface to a stated roughness, so it goes into a lathe, a grinder or a bearing seat with no preparatory cut. The hot rolled range runs 16 to 125 mm; the bright range runs 5 to 115 mm, and below 16 mm bright is the only route Laxcon supplies.

For a rotating shaft with a specified straightness and a j6, f7 or f8 fit, the precision shaft quality bar is the next step up from bright: the same finishing routes, held to tighter straightness and to the fit classes rather than the plain h classes.

Frequently Asked Questions

What stainless steel bright bar sizes does Laxcon manufacture?

Laxcon manufactures stainless steel bright bars from 5 mm to 115 mm, in lengths up to 6.5 metres.

Which tolerances and finishes are available for bright bars?

Stainless steel bright bars can be supplied to h7, h8, h9, h10, h11, k12, k13 or ASTM A484 tolerances. Finishing routes include cold drawing, centreless grinding, peeling and polishing, rough peeling and smooth turning, with surface finish down to Ra 0.2 micron.

What testing and end-finishing options are available?

On stainless steel bright bars, PMI grade confirmation is standard product information, eddy-current testing is available on request, and ends can be supplied plain or chamfered at 30, 45 or 60 degrees.

How can stainless steel bright bars be packed and traced?

Laxcon packs stainless steel bright bars in standard bundles of 500 to 1,000 kg with HDPE or LDPE wrapping and two lifting slings. ISPM 15 wooden boxes and fibre-tube packing are available, and every bundle is marked with heat number, grade, size, and net and gross weight.

What should an RFQ for stainless steel bright bars include?

An enquiry for stainless steel bright bars is quotable when it states the grade, governing standard, metric size or profile, tolerance, finish or heat-treatment condition, length, quantity, test or inspection requirement, and delivery destination.

CATALOGUE