About This Service
Hot Oil Flushing & Filtration for Superior System Cleanliness
Rays Technical Services provides Hot Oil Flushing and Filtration Services for critical hydraulic and lubrication systems in accordance with NAS 1638 / ISO 4406 cleanliness standards.
We ensure system reliability by removing contaminants, varnish, and debris that affect hydraulic performance. Our flushing rigs are equipped with certified filters and particle counters to deliver results up to NAS 5/6 cleanliness level.

Engineering Services
Flushing and Filtration. Clean Oil, Every System.
Rays Technical Services offers two structured oil cleanliness services, designed to protect hydraulic, lube, and control oil systems.
Hot Oil Flushing For Hydraulic, Lube & Control Oil Systems
A complete hot oil flushing and chemical cleaning service that removes contaminants, varnish, and debris affecting hydraulic performance, in accordance with NAS 1638 / ISO 4406 standards.
Suited to
- Hydraulic oil systems
- Hydraulic oil systems
Our flushing rigs are fitted with certified filters and particle counters, delivering results up to NAS 5/6 cleanliness level and restoring system reliability.
Filtration & Oil Analysis For On-Site & Workshop-Based Requirements
A flexible filtration service using certified filtration rigs, supported by oil sampling and condition analysis, delivered on site or in our workshop. Every job is monitored with real-time particle counts and closed out with complete flushing records.
Suited to
- High-velocity flushing with real-time monitoring
- High-velocity flushing with real-time monitoring
- High-velocity flushing with real-time monitoring
Our flushing rigs are fitted with certified filters and particle counters, delivering results up to NAS 5/6 cleanliness level and restoring system reliability.
How It Works
One process. Measured cleanliness. Complete records.
Clean oil is the fastest way to protect hydraulic performance. In many cases, a proper flush restores reliability before any costly component is replaced.
Assessment
System, oil condition, and target cleanliness are evaluated
Flushing
Hot oil flushing removes contaminants, varnish, and debris
Monitoring
Particle counts are tracked in real time throughout
Reporting
Flushing records are issued with a NAS report
How It's Delivered
Cleanliness is our responsibility. Every flush is professionally monitored and measured. Delivered on site or in our workshop using certified filtration rigs.
View DatasheetStandards & Compliance
- ISO 9001:2015 | ISO 4406
- NAS 1638
- DNV GL
- ADNOC HSE


