Premier Control Technologies

Flow, pressure, level and temperature solutions

Drastar Pressure Regulators: Commonly Asked Questions

We offer a comprehensive range of Pressure Regulators from Drastar; Single Stage and Two-Stage Pressure Regulation, Low and High Pressure / Hydraulic and Gar Reducing Regulators, Auto Change Over Systems and pressure regulation for Ultra-High Purity Systems for corrosive gases.

Below are a few Q&A’s, and we do invite you to contact us if you have some specific questions about your application.

Question: How does a pressure reducing regulator work?

Answer: A very commonly asked question asked of both our pressure reducing valve and pressure regulator series. Please see our explanation written in a separate article called - How Does an Instrumentation Pressure Regulator Work?

Question: What is the difference between a single-stage and a two-stage pressure regulator?


Single-stage regulators

Single-stage regulators are commonly used as “line regulators” or Point of Use Regulators. They are used to reduce the pressure of a ring-main or common supply to whatever is required locally or for a particular machine or piece of equipment. The common supply pressure is kept both stable and relatively high to ensure that all users obtain their pressure/flow requirements. The single stage pressure reduction is very precise because the higher inlet pressure is itself stable.

Two stage regulators

Two stage regulators are used on gas cylinders to overcome the effects of the depleting pressure within the gas bottle. This is due to the changing balance of forces within a mechanical regulator whereby the outlet pressure of the first stage actually increases as the bottle pressure decreases. The second stage of regulation smooths out this intermediate pressure setting to lower it, and to precisely maintain, the lower set-point value. Our gas cylinder regulators or gas cylinder valves are available with brass or 316L stainless steel bodies and in ultra-high purity construction.

Question: Can your regulators be used to automatically switch from an empty bottle to a new one?

Answer: Yes. When a continuous process must never run out of gas then an auto-changeover regulator can be connected to two gas bottles even though only one is being used at a time. When cylinder one depletes to a given low set value the mechanism automatically changes to the second, full, cylinder. Cylinder one can now be replaced. Over time, cylinder two will also get depleted so it will in turn switch back to the now full cylinder one. Please see our Drastar AC700 and AC720 series.

Question: Can your regulators be used as water pressure regulators?

Answer: Yes, virtually all of our single-stage line regulators can be used for water service provided that they are pre-set with the correct trim. Depending on the application, customers can choose either a brass or a 316L stainless steel body with the former being very much more cost effective. Furthermore, many other liquids can be controlled depending on the compatibility of wetted parts and the calculation of the correct Cv. All liquids should be filtered and free of particulates.

Question: Can your regulators be used as Nitrogen Pressure Regulators?

Answer : Yes, our gas regulators are ideal for both industrial and ultra-high purity Nitrogen. We have solutions for very high pressure (10,000 psig, 700 bar), very low pressure (inches water column, mbar), both high flow and very low (zero) flow, high temperatures (700 C) down to low temperature (below -150 C).

Get in touch with your questions

If you have a quesiton which has not been covered in the above article please do get in touch and our specialist engineers will be able to assist you.