Pressure regulators
Pressure regulators are designed to enhance system performance by keeping the pressure constant, or below a certain limit, within a fluidic system. A constant back pressure will often improve pump check valve efficiency and thus flow rate consistency, and it also tends to limit issues with outgassing and bubble formation.
When pressure regulators are applied to limit the total pressure within a fluidic system, they are called pressure relief valves. In these assemblies, the pressure regulators are configured via a three-way connector to divert fluid flow from the main path when the inline pressure exceeds the set limit.
Biotech Fluidics provides range of back pressure regulator (BPR) products, including a wide selection of BPR Cartridges with different opening pressures for conventional flow system sizes, plus an Adjustable BPR, and a set of Ultra-Low Volume BPRs for microfluidic systems.
The range of BPR Cartridges fits into BPR Holders of different materials, to form a wide range of BPR Assemblies for a variety of different flow system designs and requirements. Each BPR Assembly item includes a preset BPR Cartridge within a BPR Holder plus fittings for 1/16″ OD tubing.
Back Pressure Regulator Assemblies
Each of the Back Pressure Regulator (BPR) Assemblies in the comprehensive line of Biocompatible and Stainless Steel BPR Assemblies, comes complete with a replaceable, factory preset cartridge (except the 5 and 20 psi versions, which cannot be replaced). The BPR Assemblies create incremental back pressures ranging from 5 to 1,000 psi (0.3 to 69 bar). The Biocompatible BPR Assemblies feature a PEEK holder; polymer-based fittings; biocompatible BPR cartridges and wrenches for tightening. Stainless Steel BPR Assemblies feature the same biocompatible BPR cartridges with a 316 stainless steel holder and polymer fittings.
The recommended operating flow rate range for our BPR Assemblies is 0.1 mL/min up to 10 mL/min. Within this range, the amount of back pressure created by the BPR Cartridges and Assemblies will not vary more than ±10%. Lower or higher flow rates may result in larger pressure fluctuations.
| Prod. No.* | Pressure Setting | Holder Material | Includes | Swept Volume |
|---|---|---|---|---|
| P-790 | 5 psi (0.3 bar) | PEEK | P-215 (2), P-200 (2) | 134 µL |
| P-791 | 20 psi (1.4 bar) | PEEK | P-215 (2), P-200 (2) | 134 µL |
| P-785 | 40 psi (2.8 bar) | PEEK | P-761, P-215 (2), P-200 (2) | 131 µL |
| P-786 | 75 psi (5.2 bar) | PEEK | P-762, P-215 (2), P-200 (2) | 131 µL |
| P-787 | 100 psi (7 bar) | PEEK | P-763, P-215 (2), P-200 (2) | 131 µL |
| P-788 | 250 psi (17 bar) | PEEK | P-764, P-235 (2), P-200 (2) | 102 µL |
| P-789 | 500 psi (34 bar) | PEEK | P-765, LT-115 (2), P-250 (2) | 96 µL |
| P-455 | 1,000 psi (69 bar) | PEEK | P-766, LT-115 (2), P-250 (2) | 89 µL |
| U-605 | 40 psi (2.8 bar) | SST | P-761, P-201 (2), P-200 (2) | 129 µL |
| U-606 | 75 psi (5.2 bar) | SST | P-762, P-201 (2), P-200 (2) | 129 µL |
| U-607 | 100 psi (7 bar) | SST | P-763, P-201 (2), P-200 (2) | 129 µL |
| U-608 | 250 psi (17 bar) | SST | P-764, P-201 (2), P-200 (2) | 99 µL |
| U-609 | 500 psi (34 bar) | SST | P-765, P-201 (2), P-200 (2) | 93 µL |
| U-610 | 750 psi (52 bar) | SST | P-795, LT-115 (2), P-250 (2) | 91 µL |
Back Pressure Regulator Holders
The P-465 PEEK and U-469 Stainless Steel BPR Holders work with any of our replacement BPR Cartridges. Each holder comes with fittings for 1/16” OD tubing (see below). The U-469 Holder is surface-treated to prevent galling, a potential problem with large, threaded metal parts.
Please Note that these BPR Holders are designed to allow each cartridge to operate at its stated pressure setting when tightened to 20 in–lbs. of torque. To approximate this level of torque, first finger tighten the Holder, then tighten an additional 1/8 –1/4 turn with the supplied wrenches.
| Prod. No.* | Pressure Setting | Holder Material | Includes | Swept Volume |
|---|---|---|---|---|
| P-761 | Biocompatible BPR | PEEK | P-250 (2), LT-115 (2) | 7 µL |
| P-762 | High Pressure BPR | Stainless-steel | F-300 (2) | 4 µL |
Back Pressure Regulator Cartridges
The BPR Cartridges are constructed from PEEK, ETFE, perfluoroelastomer, and gold-plated stainless steel. These replacement cartridges will operate in any of the standard BPR holders shown on this webpage. These cartridges create back pressures of 40, 75, 100, 250, 500, 750, and 1,000 psi, respectively.
The recommended operating flow rate range for our BPR Cartridges is 0.1 mL/min up to 10 mL/min. Within this range, the amount of back pressure created by the BPR Cartridges and Assemblies will not vary more than ±10%. Lower or higher flow rates may result in larger pressure fluctuations.
| Prod. No.* | Pressure Setting | Body Color | End-Cap Color | Swept Volume |
|---|---|---|---|---|
| P-761 | 40 psi (2.8 bar) | Tan | Blue | 125 µL |
| P-762 | 75 psi (5.2 bar) | Tan | Yellow | 125 µL |
| P-763 | 100 psi (7 bar) | Tan | Red | 125 µL |
| P-764 | 250 psi (17 bar) | Tan | White | 95 µL |
| P-765 | 500 psi (34 bar) | Tan | Green | 89 µL |
| P-795 | 750 psi (52 bar) | Black | Blue | 87 µL |
| P-796 | 1,000 psi (69 bar) | Black | Green | 83 µL |
Pressure Relief Valves
The Pressure Relief Valves from Biotech Fluidics are ideal for preventing system over-pressurization. These products protect system components by diverting fluid flow automatically when inline pressure exceeds the set limit. Choose between preset 100 psi (7 bar) and 5 psi (0.3 bar) assemblies, both shipped with Flangeless Fittings. The 100 psi version is a good, general purpose valve, while the 5 psi version is perfect for protecting syringe and peristaltic pump systems. The void volume of both relief valves is low due to the small 0.020” (0.50 mm) thru-holes in the valve tee body.
If you wish to have the Pressure Relief Valve open at a different pressure than 5 or 100 psi, simply combine one of the other replacement Back Pressure Regulator Assemblies with the P-612 Pressure Relief Valve Tee.
| Prod. No.* | Description | Pressure Setting | Tubing OD | Includes | Swept Volume |
|---|---|---|---|---|---|
| U-455 | Pressure Relief Assembly | 5 psi (0.3 bar) | 1/16” | P-201 (2), P-200 (2) | 148 µL |
| U-456 | Pressure Relief Assembly | 100 psi (7 bar) | 1/16” | P-201 (2), P-200 (2), wrenches | 139 µL |
| P-612 | Pressure Relief Tee Only | - | 1/16” | P-201 (2), P-200 (2) | 14 µL |
Ultra-Low Volume Back Pressure Regulators
The Ultra-Low Volume Back Pressure Regulators (BPRs) were developed to minimize swept volume, which is especially important for multi-detector applications. With a maximum swept volume of only 6 µL, it is nearly impossible to detect these BPRs as part of your fluid pathway. To minimize the swept volume added to your flow path, we recommend trimming the length of the attached tubing. Full biocompatibility is assured since the flow path is completely polymeric.
Please note that our Ultra-Low Volume Back Pressure Regulators cannot be used as check valves due to their unique internal design. For such applications we recommend the Micro-Volume Inline Check Valves instead.
| Prod. No.* | Back Pressure Setting | Flow Rate Recommendations | Recommended Pressure Range | For Tubing | Swept Volume | Includes |
|---|---|---|---|---|---|---|
| M-410 | 100 psi (7 bar) @ 0.5 mL/min | Optimal: 0.1–1 mL/min Max.: 4 mL/min | 40–150 psi (3–10 bar) | PEEK, 1/16" OD, 0.010” ID | 6 µL | P-230, P-200 |
| M-412 | 500 psi (34 bar) @ 0.5 mL/min | Optimal: 0.1–1 mL/min Max.: 4 mL/min | 250–525 psi (17–36 bar) | PEEK, 1/16" OD, 0.010” ID | 6 µL | P-230, P-200 |
| M-420 | 100 psi (7 bar) @ 5 mL/min | Optimal: 3–8 mL/min Max.: 10 mL/min | 40–150 psi (3–10 bar) | PEEK, 1/16" OD, 0.020” ID | 6 µL | P-230, P-200 |
Adjustable Back Pressure Regulator
The biocompatible P-880 High Pressure Adjustable BPR offers the flexibility to adjust your system back pressure between 2,000 – 5,000 psi (138 – 345 bar), independent of the flow. Only 10% fluctuation in pressure generally occurs with flow rates of 0.1–10 mL/min. Lower or higher flow rates will lead to greater fluctuations in pressure. To achieve the desired back pressure setting, simply turn the thumbscrew while monitoring your system pressure. Because this product creates such high back pressure, please check system component specifications prior to using to avoid damaging any sensitive components.
| Prod. No.* | Pressure Setting | Material | Includes | Swept Volume |
|---|---|---|---|---|
| P-880 | 2,000–5,000 psi (138-345 bar) | PEEK, PTFE, and perfluoroelastomer | F-120BLK (2) | 9 µL |
