Dicrest HIC Resistant Steel

High Pressure Production Trap made of Dicrest 5 HIC Resistant Steel

High Pressure Production Trap made of Dicrest 5 HIC Resistant Steel

HIC Resistant Steel is designed to operate in a sour service environment, that is where the oil or gas has a high H2S. In a sour service environment hydrogen induced cracking can cause failure in normal boiler plates such as ASTM A516 Grade 70. HIC Resistant Steel that is resistant to these effects. It is normally specified by TM0284 or EN10229 with the acceptance classes specified in EN10028-3.

We have one of the largest stocks of Dicrest HIC Resistant steel in Europe with plate thicknesses up to 100mm. The plates are ASTM/ASME A516 grades 60/65/70 (triple certified) and are all from Dillinger Hutte in Germany.

Dicrest is a pressure vessel steel that is specifically designed to be resistant to HIC (Hydrogen Induced Cracking) for sour service use in the oil and gas industry. It meets or exceeds the requirements of the majority of oil majors and national oil companies. It is a reliable and approved choice for sour service use.

HIC resistant steel is a carbon steel plate, such as A516 grade 70, which has been further tested to demonstrate that it is resistant to hydrogen induced cracking.

The HIC resistant steel plate must meet all the standard requirements of the grade – such as chemical composition and have the same mechanical properties – but the manufacturing process has been developed so that when the steel is tested the cracks that form have certain maxima. This gives designers the confidence to use carbon steel boiler plate in sour service avoiding much more expensive stainless steel plate.

It is mainly used for pressure vessel and boiler manufacture in the oil and gas and petrochemical industries where the oil has high sulphur content – known as sour service. Whilst more expensive than normal carbon steel boiler plate, it is significantly cheaper than stainless steel whilst having improved cracking resistance helping to reduce maintenance and full life costs – as well as improved safety over standard boiler plate.

When steels are evaluated for resistance (not immunity) to HIC one of the key factors is the level of sulphur in the steel and typically maximum allowable levels are 0.003% in plates if the acceptance tests in TM0284 are to be met.

Dicrest HIC Resistant Steel Technical Specifications

Chemical Composition

Dicrest Steel Chemical Composition

Steel Grade
Thickness
C
Si
Si (Min)
Mn
Mn (Min)
P
S
A516 60≥100 and ≤200mm0.270.450.131.30.790.0350.035
A516 60>200mm0.270.450.131.30.790.0350.035
A516 60≤12.5mm0.210.450.130.980.550.0350.035
A516 60≥12.5 and ≤50mm0.230.450.131.30.790.0350.035
A516 60≥50 and ≤100mm0.250.450.131.30.790.0350.035
A516 65 Dicrest only≥100 and ≤200mm0.290.450.131.30.790.0350.035
A516 65 Dicrest only≥12.5 and ≤50mm0.260.450.131.30.790.0350.035
A516 65 Dicrest only≤12.5mm0.240.450.131.30.790.0350.035
A516 65 Dicrest only>200mm0.290.450.131.30.790.0350.035
A516 65 Dicrest only≥50 and ≤100mm0.280.450.131.30.790.0350.035
A516 70≥50 and ≤100mm0.30.450.131.30.790.0350.035
A516 70≥100 and ≤200mm0.310.450.131.30.790.0350.035
A516 70≤12.5mm0.270.450.131.30.790.0350.035
A516 70>200mm0.310.450.131.30.790.0350.035
A516 70≥12.5 and ≤50mm0.280.450.131.30.790.0350.035
This table provides the main features of the chemical composition of different grades as required by the relevant standards. It is not complete as we have not included many of the minor use cases. These may have a major impact in your application so please use this for reference purposes only and refer to your original and upto date copy of the relevant standard

 

EN 10028–3 – Annex A Requirements

These set out the acceptance criteria for plate that is for sour service use. Dicrest is designed for sour service use and the whole manufacturing process from steel making, to casting to rolling is designed to make it the best HIC plate available. This gives it a significant quality advantage over standard pressure vessel plates that are rolled and then tested to see if they meet the requirements. (You can buy a copy of EN10028-3 here)

CSR = Crack to Length Ratio

CTR – Crack to Thickness Ratio

CSR – Crack Sensitivity Ratio

Type of HIC Resistant Steel Plate

There are three acceptance classes for HIC plates under EN 10028–3. Each acceptance class sets requirements for the maximum permissible % of the crack to length ratio (CLR), the crack to thickness ratio (CTR) and the crack sensitivity ratio (CSR).
Acceptance class I is the most resistant, followed by II and then III.
The table below shows the acceptable test results using Test Solution A (pH3).
Acceptance Class
Grade Offered
CLR %
CTR %
CSR %
IDicrest 5≤ 5≤ 1.5≤ 0.5
IIDicrest 10≤ 10≤ 3≤ 1
IIDicrest 15≤ 15≤ 5≤ 2

 General

HIC plate is a carbon steel plate, such as A516 grade 70, which has been further tested to demonstrate that it is resistant to hydrogen induced cracking.

The steel plate must meet all the standard requirements of the grade – such as chemical composition and have the same mechanical properties – but the manufacturing process has been developed so that when the steel is tested the cracks that form have certain maxima. This gives designers the confidence to use carbon steel boiler plate in sour service avoiding much more expensive stainless steel plate.

It is mainly used for pressure vessel and boiler manufacture in the oil and gas and petrochemical industries where the oil has high sulphur content – known as sour service. Whilst more expensive than normal carbon steel boiler plate, it is significantly cheaper than stainless steel whilst having improved cracking resistance helping to reduce maintenance and full life costs – as well as improved safety over standard boiler plate.

When steels are evaluated for resistance (not immunity) to HIC one of the key factors is the level of sulphur in the steel and typically maximum allowable levels are 0.003% in plates if the acceptance tests in TM0284 are to be met.

You can get HIC resistant plate in the following ASTM grades. A516 gr 70, A516 gr 65 and A516 gr 60 in fact all our Dicrest HIC steel plates are triple certified to A516/60/65/70 + HIC

For customers in Europe Dicrest can be ordered direct from Dillinger or from stock from AncoferWaldram