Steel FAQs
Find answers to frequently asked questions about the materials and services offered by leading UK steel stockholder Hillfoot.
What is BS 970?
The national steel standard which contains many of the engineering grades of steel supplied by Hillfoot.
What is forged bar steel?
Bar which has been hot worked by forging, using either presses or hammers, to produce a final wrought structure of a given sectional size. It is typically adopted on section sizes greater than 300mm diameter, though can be produced in smaller sizes.
Forged products can be produced in a variety of shapes and sizes which are closer to net sizes, thus reducing machining time and volume of raw material.
What is rolled bar steel?
Bar which has been hot worked by passing through a series of profiled rollers, reducing the cross section to produce a final wrought structure of a given sectional size. It is typically adopted on section sizes up to 300mm diameter, though it is possible to produce greater diameters by rolling.
What is ground bar steel?
A method of producing bright bar, typically adopted on small diameter bar. Grinding produces very tight dimensional tolerance and high surface finishes.
What is peeled bar steel?
A method of producing bright bar, typically adopted on diameters under 4”, achieved by a bar passing through a peeling head containing multi-point radial cutting tools. This method is preferred over drawn bar for components requiring localised/induction hardening.
What is rough turned bar steel?
It is similar to turned bar but with a lesser surface finish and dimensional tolerance.
What is turned bar steel?
This is a method of producing bright bar steel typically used on diameters over 4” and achieved by turning between centres. The straightness of a bar is significantly improved when this method is utilised.
What is bright bar steel?
These are materials supplied by Hillfoot with subsequent machining to the outside surface following hot rolling or forging. This ensures all surface defects, oxides and decarburisation present from the rolling/forging process are removed from the surface, as well as improving dimension tolerance, resulting in less material removal being needed to achieve finished dimensions.
What is black bar steel?
These are materials supplied by Hillfoot with no subsequent machining to the outside surface following hot rolling or forging. Black bar exhibits minor surface defects from the hot working process.
What is non-destructive testing?
Testing which does not involve any mechanical destruction of material, such that tests may be carried out on the actual components. Tests include ultrasonic, magnetic particle and X-ray.
What is destructive testing?
Testing which involves the mechanical destruction of material, such that a separate test piece is required. Tests include tensile, impacts, Jominy and metallography.
Can Hillfoot organise third-party witness testing?
Yes, Hillfoot can arrange testing by a number of IACS members, including:
IACS Member | Abbreviation | Website |
Lloyds Register of Shipping | LR | |
Det Norske Veritas/ Germanischer Lloyd | DNV GL | |
American Bureau of Shipping | ABS | |
Bureau Veritas | BV | |
China Classification Society | CCS | |
Croatian Register of Shipping | CRS | |
Indian Register of Shipping | IRS | |
Korean Register of Shipping | KR | |
ClassNK | NK | |
Polish Register of Shipping | PRS | |
Rina Services | RINA | |
Russian Maritime Register of Shipping | RS |
What is third-party witness testing?
Witness testing and 3.2 release of material by IACS member organisations to verify material properties such as chemical analysis, mechanical properties and material integrity.
What is drawn bar steel?
A method of producing a bright bar, typically adopted on diameters under 4”, achieved by pulling bars through a series of consecutive dies in the cold state to reduce the section to the required size. Surface quality and dimensional tolerance is typically better than peeled bar.
What type of metallurgical services do Hillfoot provide?
Our services include product design for application and production improvements through material development.
Please contact us for full details.
What is solution anneal & aging?
A two or three-step heat treatment commonly applied to precipitation hardening steels to create high strengths. The first stage is to solution anneal which creates a readily machinable state, with the subsequent stage(s) creating high strength with the benefit of minimal material distortion.
What is stress relieve?
An optional heat treatment process most often carried out on quenched and tempered material. It is designed to remove internal stress inherent in the material from both the manufacturing and heat treatment stages, thus increasing dimensional stability during subsequent machining operations.
What is annealing?
The annealing process is similar to the normalising process except that the steel after heating and soaking is allowed to cool inside the furnace - at a much slower cooling rate. This slower cooling rate produces a coarser, softer structure and is often applied prior to machining.
What is quench & temper?
Quenching and tempering produces superior combinations of strength and ductility than other heat treatments. It involves a two stage process; an initial heating and rapid quenching to produce maximum hardness, followed by a tempering process to reduce brittleness and promote toughness.
What is normalising?
Normalising is a heat treatment applied to castings, forgings and other forms of wrought steel to refine their grain size and hence improve their mechanical properties.
Do Hillfoot offer steel honing services?
Yes, for tolerances typically less than 0.010” (0.254mm).
What facilities do Hillfoot have for boring?
Precision Boring to the following requirements:
- TOLERANCE: +-/0.020” (+/-0.508mm)
- TIR: 1/1000mm
- LENGTH: 10 MTR max
Rough Boring to the following requirements:
- TOLERANCE: +0/-2mm
- LENGTH: 10 MTR max
If you are looking for any other tolerance please contact us.
What steel forging services do Hillfoot offer?
We can provide open and closed die forgings to produce products near to net shape, thus minimising machining and waste. Bi-directionality can also be created within the material grain structure giving similar mechanical properties in all directions.
What billeting and sawing services do Hillfoot offer?
Band Saw - This is the market standard for billeted goods. Tolerance can vary based on diameter; please contact us for details.
Carbide Saw - This provides faster cutting for volume-based requirements, offering improved surface finish and dimensional tolerance. Typically -0/+0.5mm is achieved, but it is possible to offer a datum face with a -0/+0.1mm length tolerance.
What packaging solutions do Hillfoot use?
We typically use pallets, sacks, shrink wrapping, bespoke crates and re-usable stillages.
If you are looking for any other requirements please contact us.
What is Future One?
The process we use to ensure a strategically managed approach on contractual business.
Click here to find out more about Future One.
Which approvals do Hillfoot have?
Hillfoot carry approvals from major global OEMs in Oil & Gas, Mining, Defence, Off Highway, Automotive and Rolls-Royce.
Please contact us for further information.
We are also ISO 9001 Quality Management, ISO 14001 Environmental Management and OHSAS 18001 Health & Safety Management accredited.
Click here to download copies of Hillfoot’s ISO 9001, ISO 14001 and OHSAS 18001 certificates.
What type of supply chain solutions do Hillfoot offer?
We offer full or partial supply chain management solutions that provide commercial, operational and technical improvements for you and your subcontractors.
What export services do Hillfoot offer?
Hillfoot have an established international metals supply service and can deliver materials anywhere in the world. Read full details.
What is sub-critical annealing / process annealing / spheroidising?
Sub-critical / process annealing is similar to the annealing process but is performed at a lower temperature. It restores some of the ductility of cold worked steels and is often performed as intermediate treatment to prevent cracking and allow further shaping.
It can be also used on medium-high carbon and alloy steels to improve machinability by reforming their structure (spheroidising).
Can Hillfoot offer JIT (line-side delivery)?
Yes, we have experience of just in time delivery for Kanban where customers need line side timed deliveries for lean manufacturing processes.
What is consignment stock?
Stock held at customer site specifically for contractual requirements. This can be standard grades of material or product designed to meet a particular customer’s needs or application.
What is bespoke / dedicated customer stock?
Stock held by Hillfoot for specific contractual requirements. As part of our services, we can hold standard grades of steel or product designed to meet the customer’s particular needs or application.
What turning / peeling services do Hillfoot offer?
NOMINAL SIZES | TOLERANCES | ||||||
| Tolerances in Millimetres. The total tolerance is taken as MINUS. | ||||||
| i.e. 45mm dia h9 = -0.062 | ||||||
mm | h13 | h12 | h11 | h 10 | h9 | h8 | h7 |
> 1 to 3 | 0.140 | 0.100 | 0.050 | 0.040 | 0.025 | 0.014 | 0.010 |
> 3 to 6 | 0.180 | 0.120 | 0.075 | 0.048 | 0.030 | 0.018 | 0.012 |
> 6 to 10 | 0.220 | 0.150 | 0.090 | 0.058 | 0.036 | 0.022 | 0.015 |
> 10 to 18 | 0.270 | 0.180 | 0.110 | 0.070 | 0.043 | 0.027 | 0.018 |
> 18 to 30 | 0.330 | 0.210 | 0.130 | 0.084 | 0.052 | 0.033 | 0.021 |
> 30 to 50 | 0.390 | 0.250 | 0.150 | 0.100 | 0.062 | 0.039 | 0.025 |
> 50 to 80 | 0.460 | 0.300 | 0.190 | 0.120 | 0.074 | 0.046 | 0.030 |
> 80 to 120 | 0.540 | 0.350 | 0.220 | 0.140 | 0.087 | 0.054 | 0.035 |
> 120 to180 | 0.630 | 0.400 | 0.250 | 0.160 | 0.100 | 0.063 | 0.040 |
Can we help?
Anything from trade accounts, to delivery options - drop us an enquiry and we’ll be straight back to you.
Alternatively, you can always just call us!