Vicente Reynal
Chief Executive Officer at Ingersoll Rand
Thank you, Vik. And moving to Slide 12. Starting with Industrial Technologies and Services. Overall, organic orders were up 41% and revenue up 17%, leading to a book-to-bill of 1.15. In addition, the team delivered strong adjusted EBITDA of 41% and adjusted EBITDA margin of 24.7%, up 250 basis points year-over-year, with incremental margin of 34%. Let me provide more detail on the order performance. Starting with compressors, we saw orders up in the mid-40%.
A further breakdown into oil-free and oil-lubricated products shows that orders for both were up above 40%. From a regional split for orders on compressors, in the Americas, North America performed strong at up low 40%, while Latin America was up in the mid-70%. Mainland Europe was up low 50%, while India, Middle East, saw continued strong recovery with order rates up in excess of 100%. Asia Pacific continues to perform well with orders up low 30% driven by low 30% growth in both China and high 20% across the rest of Asia Pacific.
From a vacuum and blower perspective, orders were up in mid-40s, on a global basis with strong double-digit growth across each of our regions. In power tools and lifting, the total business was up high 50% in orders and so continued positive growth driven mainly by our enhanced e-commerce capabilities and improve execution on new product launches. On the right-hand side, we're highlighting one of our new exciting products, which is a result of our continued commitment to organic investments in our portfolio.
In this case, during Q2, we completed the launch of our new line of refrigerated drive portfolio. That's a bit of a background. The basic function of the air dryer is to remove moisture from the air by cooling it with a refrigerant. Does the water vapor is condensed and the air can be easily compressed. The result is dry compressed air, which can be used in compressed air equipment without causing any damage. Air dryer technology is sold as an accessory to all rotary oil-lubricated and oil-free air compression technology. So it is a great adjacent technology that increases the total quality of air provided to the customer.
This is a very important requirement, especially in oil-free compression where customers demand high air quality in terms of dryness and particulate. It is also good to note that it is a great aftermarket generator as the filters or desiccant need to be changed often. In this case, we leverage a technology developed at [Indecipherable], which was accompanied owned by legacy Ingersoll Rand. Since the merger of Gardner Denver and IR, not only we have accelerated our organic investments in new products [Indecipherable], but we're now leveraging the technology in order to serve Gardner Denver, Ingersoll Rand and in the future, even our champion compressor customers.
The even more exciting piece here is that we're doing this while helping the environment. This new driver portfolio is 20% more energy-efficient and reduces greenhouse gas emissions by over 50%. Moving to Slide 13 and the Precision and Science Technology segment, overall, organic orders were up 20% driven by, i.e., the Medical and Dosatron businesses, which serve lab, life science, water and animal health markets. These businesses were up double digits. And we also saw strong performance in our ARO and Milton Roy product lines.
The momentum in our Haskel Hydrogen Solution business continues to build, and we saw some strong funnel activity. Revenue was up 12% (sic) [13%] organically, which is encouraging, as we have some tough comps due to COVID-related orders and revenue in Q2 2020 for the Medical business. Additionally, the PST team delivered strong adjusted EBITDA of $71 million, which was up 20%. Adjusted EBITDA margin was 30.7%, up 40 basis points year-over-year, with incremental margins of 33%.
Today, we want to highlight our hydrogen refueling business to give you an update on where we are and investments we're making. As we have discussed before during our Q4 earnings call, we made investments in developing a hydrogen dispensing unit leveraging our Haskel high-pressure technology, and we're now ready to capture the growth in this business. We have line of sight to about $45 million in organic investments over the next five years to both build out our capacity and fund ongoing product development in the hydrogen refueling space, with approximately $10 million of this investment expected in the next 12 months.
Since our last call, we have seen our funnel grow 3 times to over $250 million in potential projects. And we still feel confident that this is a business where we will see meaningful growth for years to come, driving our decision to expand two of our factories in Europe to support anticipated growth. In addition, we want to highlight that Ingersoll Rand is designing and developing a state-of-the-art hydrogen refueling stations to support the power and remote joint venture. Moving to Slide 14. Given the comp performance in Q2 and continued strong outlook, we're increasing guidance for 2021. Our guidance excludes both the High Pressure Solutions and the Specialty Vehicle Technology segments as well as the pending acquisition of Seepex and Maximus.
Our prior revenue guidance was up low double digits on a reported basis, comprised of high single-digit organic growth across both of our segments. And we're now open guiding up to be mid-teens in total with low double-digit organic growth across both segments. This reflects approximately 250 to 300 basis point growth in organic growth for the total company as compared to prior guidance.
FX is expected to continue to be a low single-digit tailwind, and based on these revenue assumptions, we're increasing 2021 adjusted EBITDA guidance to $1.15 billion to $1.18 billion, which represents approximately a $30 million improvement from power guidance at the midpoint of the range. We also highlight that these also includes the increased corporate cost of approximately $6 million per quarter for both Q3 and Q4 as compared to prior guidance, as mentioned on the right-hand side of the slide. In terms of cash generation, we expect free cash flow to adjusted net income conversion to remain greater than or equal to 100%. capex is expected to be approximately 1.5% of revenue.
And finally, we expect our adjusted tax rate for the year to be approximately 20%, and this does include a $35 million benefit due to a tax restructuring plan that was recently completed, that is reflected approximately 40% in the Q2 rate with the balance in the second half of the year. Moving now to Slide 15. As we wrap today's call, Ingersoll Rand brand is in an outstanding place. 2021 is poised to be a great year. To our employees, I want to say thank you for how we come together every day to be there for our customers, solve problems, lean on each other and collaborate. We take our role as sustainably-minded industry leader seriously, and our employees eagerly embrace IRX to put us in that leadership position. I am confident we will continue to transform Ingersoll Rand and deliver increased value to all of our shareholders.
So with that, I'll turn the call back to the operator and open for Q&A.
