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High Performance Pressure Regulators  Series PRHM

 

 

plastic pressure regulatorFeatures: Series PRHM design incorporates a poppet seat, double u-cups, large area rolling diaphragm and one piece body construction. A pressure balanced shaft assures smooth and stable control, while the valve design provides excellent flow performance.

• Pressure setting is infinitely adjustable from 5 psi to 125 psi 
• Maximum inlet pressure is 150 psi 
• Non-rising adjusting bolt. 
• High performance, heavy-duty design with optional gauge ports. 
• Designed for low maintenance and easy to adjust.

Materials and Piping Connections

Standard body materials offered are in Geon PVC, Corzan CPVC, Natural Polypropylene, or Kynar PVDF. Some Kynar PVDF components are used in the Natural Polypro models for strength. Standard seal materials are EPDM or FKM (Viton). Corrosion-resistant design has no wetted metals and is also excellent for high purity and water applications. Springs and fasteners (not wetted) are stainless steel. Optional Xylan coated springs and fasteners available; consult factory.

The standard connections are female NPT threaded ports. Socket, flanged, spigot, flare, BSP, DIN, JIS and custom connections are also available.

Design

Plast-O-Matic Pressure Regulators are designed to handle corrosive and ultra-pure liquids with inlet pressures up to 150 PSI at 75°F. Standard down-stream set pressure range is 5 to 125 PSI. The normally-open regulators incorporate a poppet seat at the valve orifice to prevent sticking and affecting the sensing of the downstream line pressure. Also, one piece body construction and dual U-cup shaft seals help to eliminate internal leakage that could cause the set pressure to creep beyond a safe limit. A unique, large surface, rolling diaphragm seal isolates the spring chamber from downstream pressure sensing liquid.

This unique design, in conjunction with a pressure balanced shaft, assures smooth performance and stable control. It is important to avoid quick closing valves downstream of a regulator to eliminate “water hammer” shock that can cause breakage to the rolling diaphragm.


Above right: PRHM in Geon PVC (Grade 1, Type 1). At left: PRHM with natural homopolymer polypropylene body. The spring housing is glass-filled polypro. Photos are representative; appearance may vary based on size and materials.


 

 

 

Dimensions and Performance Curves — Flow Capacity vs. Pressure Drop-off

Drop-off is the difference between the pressure regulator set pressure and the actual downstream pressure. Data obtained under laboratory conditions; your results may vary.

In the selection of a liquid pressure regulator, flow capacity with minimum system pressure loss are critical criteria, but it should be recognized that all similar-size competitive regulators do not provide similar performance levels. Plast-O-Matic PRHM regulators provide not only higher set pressures and flow capacities with each model, but these are achieved with less pressure losses than with similar size competitive regulators. These lower pressure drop-offs can be seen from the performance curve charts shown below.

 

 


flow performance curves of series prhm pressure regulator versus competitive valves


flow performance curves of series prhm pressure regulator versus competitive valves


flow performance curves of series prhm pressure regulator versus competitive valves


flow performance curves of series prhm pressure regulator versus competitive valves


flow performance curves of series prhm pressure regulator versus competitive valves


 

Dimensional Drawing & Part Number Reference Chart

 

For 1/4″, 3″, 4″ and all Series PRH regulators please click here.

 

pressure regulator dimensional drawing

Series PRHM Dimensions, Maximum Flow Rates, Part Numbers

Pipe Size
NPT (Spigot)

A
B
C
D
Maximum Flow*
NPT Model Number
in
mm
in
mm
in
mm
in
mm
GPM
LPM
1/2″ (20 mm)
3.19
80.96
8.75
222.25
2.13
53.98
4.94
125.41
10
37.85
PRHM050V-PV
3/4″ (25 mm)
5.50
139.70
10.12
255.00
2.38
60.33
8.81
223.84
35
132.49
PRHM075V-PV
1″ (32 mm)
5.50
139.70
10.12
255.00
2.38
60.33
9.06
230.10
50
189.27
PRHM100V-PV
1 1/2″ (50 mm)
6.06
153.99
11.94
303.21
3.00
76.20
10.00
254.00
70
264.98
PRHM150V-PV
2″ (63 mm)
6.56
166.69
11.94
303.21
3.00
76.20
10.88
276.23
100
378.54
PRHM200V-PV

 

*Note:The generally accepted safe velocity in plastic piping is five feet (5’/1.5m) per second. These maximum flow rates exceed that velocity.

PRHM(series) 050(size) V(seal material) – PV(body material)

Series Prefix: PRHM 5-125 PSI set range. 

Materials: The model numbers shown are PVC with FKM seals. To order Corzan CPVC, change -PV suffix to -CP, example: PRHM050V-CP. For Natural Polypro, change suffix to -PP; for Kynar PVDF change suffix to -PF. For EPDM seals change V- to EP-, for example, PRHM050EP-CP. Custom seal materials available; please consult factory. Minimums apply. 

For 1/4″, 3″, 4″ and other sizes not shown, as well as PTFE body materials, please refer to Series PRH, which are machined-body pressure regulators with similar dimensions and virtually identical performance.

CAD Files

PRHM 1/2″ STEP File

PRHM 3/4″ STEP File

PRHM 1″ STEP File

PRHM 1 1/2″ STEP File

PRHM 2″ STEP File

PRHM PDF Catalog 

 

Additional Info

Backpressure Valves
The pressure regulators described above are used to control downstream pressure. If you actually need to control pressure upstream, or “backpressure,” please click on this link.

Valve Pressure Loss & Flow – Q&A and Equations
(Explains Cv and Delta P, how to better specify valves, etc.)