API 570 Pipework Inspection
In-service inspection of process piping systems to API 570, from thickness monitoring at condition monitoring locations through to the next inspection interval.
About API 570 inspection
API 570 is the code for the in-service inspection of process piping systems. It covers the pipe itself along with the flanges, valves, fittings and pipe racks that make up a live line, and it sets out how that pipework should be examined, monitored and assessed while it stays in service.
We inspect pipework to API 570 to build a clear picture of wall condition across a system and to catch the localised problems that cause most piping failures. Thickness is monitored at agreed condition monitoring locations and trended over time, so wall loss is measured and tracked rather than assumed.
Small-bore lines, dead legs and injection points get particular attention, because these are where corrosion often concentrates and where a general survey can miss it.
Inspection scope
An API 570 inspection combines the survey work with the trending and calculations that show how a piping system is holding up.
- External visual inspection of lines, supports and pipe racks
- Thickness monitoring at condition monitoring and thickness monitoring locations
- Corrosion mapping to assess the extent of wall loss
- Corrosion under insulation surveys on insulated lines
- Small-bore and dead-leg assessment
- Injection point inspection
- Weld examination and non-destructive testing
- Remaining life calculation and the next inspection interval
Why API 570 inspection matters
Failures are local
Most piping problems are localised, so monitoring locations are chosen to sit where damage is likely, not spread evenly.
Dead legs and injection points
Stagnant legs and injection points corrode faster than the main line and are inspected as the higher-risk features they are.
Trended, not one-off
Readings are trended against previous surveys so corrosion rates and remaining life are based on real wall loss.
Insulation covered
CUI surveys check for wall loss hidden beneath lagging, a common cause of unexpected pipework leaks.
Reporting and recommendations
Every API 570 inspection produces a clear report rather than a raw data dump. We set out the condition of the system, the damage mechanisms identified and the readings taken, alongside recommendations that are proportionate to the risk.
Thickness data is presented against previous surveys where records exist, with calculated corrosion rates, a remaining life assessment and the recommended next inspection interval for each line or circuit. Any repairs and re-examination are called out and prioritised.
The findings support the pipework element of your written scheme of examination under the Pressure Systems Safety Regulations, and give the competent person a defensible basis for keeping lines in service.
A note on regulatory context
Process pipework in Great Britain falls under the Pressure Systems Safety Regulations in the same way as vessels, and it must be covered by a written scheme of examination and examined by a competent person. API 570 gives the recognised method for that examination, setting out where to monitor thickness, how to interpret the readings and how to set an inspection interval that reflects the real corrosion rate. Following it helps operators meet their statutory duties while keeping lines running.
Related inspection services
Need an API 570 pipework inspection?
Talk to our inspection team about thickness monitoring, corrosion mapping and inspection planning for your process piping.