Product Description & Application
The Henry Technologies High Pressure Range of pressure relief valves (PRVs) are
designed for installation on pressure vessels containing group 2 refrigerant gases and
(5700 and 5702-type models only) group 1 refrigerant gases compatible with the materials
of manufacture. Henry PRVs are certified for gas service only and therefore should not be
used to protect against liquid overpressure.
High Pressure PRV Range valves are classified as 'conventional back pressure
dependant' and are therefore required to discharge to atmospheric pressure, with zero
superimposed back-pressure and a maximum of 10% built-up back-pressure during
discharge. Upstream pressure must not exceed 3% due to piping. The valves are designed
to ensure that pressure accumulation above the set point is limited to a maximum of 10%.
Once a PRV has discharged, it is recommended to replace it as the set pressure can no
longer be guaranteed. All PRVs should be replaced every five years (or earlier if other
regulations apply). All valves are designed, manufactured and certified to the ASME BPV
Section XIII Code except the 5702LF, which is designed to the intent of the same Code.
The 5701 models are additionally certified to EN ISO 4126-1. All models are certified as
Group IV safety devices under the EU PED and UK PE(S)R.
Warnings
1.
The application, selection and installation of a relief valve should be undertaken by only suitably qualified or experienced personnel.
2.
The system should be de-pressurised before removing a PRV, unless using a three-way dual shut-off valve. Consult the appropriate three-way
valve operating instructions to ensure proper isolation of the PRV to be removed. Failure to do so could result in serious bodily injury.
3.
Do not obstruct the outlet of the relief valve or discharge piping. The provided plastic caps are intended to protect the threads during transit only.
4.
Do not exceed pressure and temperature limitations indicated on the PRV.
5.
If flammable or toxic refrigerant is used, additional measures should be employed to ensure joint integrity, leak-tightness and adequate system
leak detection. For flammable refrigerant, proximity to ignition sources shall also be considered.
6.
If being used in an R744 (CO
Recommended PRV Selection Method
1.
Determine the maximum required capacity of the valve using an appropriate standard eg. EN 13136 or ASME XIII.
2.
Calculate the rated capacity of the valve at the system conditions and ensure the valve is adequate for protecting of the system. The de-rated
coefficient of discharge (K
3.
The relief valve should be selected taking into account all processes that could result in an unexpected increase in system pressure.
4.
The use of a Henry Sentry safety device assembly is recommended to allow replacement of PRVs and to ensure hermetic sealing of the system.
5.
Gross over-sizing of a relief valve (required system capacity less than 25% of the rated PRV capacity) is not recommended.
6.
It is recommended to select the PRV setting (which must not exceed the design working pressure of the vessel) at least 25% higher than the
maximum operating pressure for the refrigerant used, to avoid accidental discharge during operation.
Installation
1.
Connect the PRV or Sentry safety device assembly directly to the pressure vessel (if using piping, ensure pressure-drop is limited to a maximum
of 3%) at a location above the liquid refrigerant level, in the vapour space. Stop valves shall not be located between the vessel and the PRV
except the three-way dual shut-off valve included in the Sentry assembly. Relief valves should be mounted as vertically as possible to avoid the
possibility of liquid refrigerant or oil pooling at the valve inlet.
2.
The discharge from the PRV shall be vented in accordance with an appropriate standard; ensuring back-pressure is limited to a maximum of 10%.
3.
EN 13136 is recommended as a reference for pressure drop calculation in both the upstream and downstream lines.
4.
Care should be taken to avoid water ingress or pooling inside the valve; particularly outdoors.
5.
Thread sealing compounds used to install PRVs should be applied with care to external threads only to avoid internal contamination.
6.
Do not lift or discharge the PRV intentionally (PRVs should be isolated or removed during the system pressure test) as this will affect the set point.
7.
Inlet and discharge pipe work must not impose loads onto the relief valve. The valve is not intended as a support.
ASME rated
Part No.
k
Slope
dr
(SCFM/PSIA)
5700
0.81
0.223
5701AX/GX
0.71
0.808
5702LF
0.52
N/A
5702/A/B/C
0.81
2.016
The table is intended for reference purposes only. Selection of a PRV should be carried out in accordance with an appropriate standard
IF IN DOUBT, CONTACT
HENRY TECHNOLOGIES
For local contact details,
select the "Contact Us" option at;
www.henry-group.net
Created on: 5/10/22, using Template: Henry IS TemplateB revA
) application, consideration should be given the risk of solid refrigerant forming downstream of the PRV.
2
), flow area (A) and ASME rated slope for all models are given below.
dr
Valve Selection Parameters & Reference Capacities (kg Air/min @ 20°C)
Flow Area,
31.0
A
450
2
9.62 mm
3.9
2
0.015 in
2
39.59 mm
N/A
2
0.061 in
2
86.59 mm
22.4
2
0.134 in
2
86.59 mm
34.9
2
0.134 in
DECLARATION OF CONFORMITY
To view and download the Declaration of Conformity for your PRV, visit:
www.henry-group.net/technical/united-kingdom
Select Products Manufactured in the UK > Pressure Relief Valves, and
open the folder matching the ID Code on your valve. Use the Model
Number (e.g. 5701AX) and Set Pressure (e.g. 120 barg) to locate, open
Pressure Relief Valves – High Pressure Range
www.henry-group.net
English
Pressure Setting (barg / PSIg)
40.0
42.0
45.0
580
609
653
5.0
5.2
5.6
N/A
N/A
N/A
28.7
30.1
32.2
44.7
46.9
50.2
or scan the QR Code opposite:
and download your DoC.
INTELLIGENT MANUFACTURING. INTELLIGENT PRODUCTS.
Application & Installation Instructions
6-025-5029 revA / ECN: S22-1948
Key
1. Inlet
2. Outlet
2
1
46.0
60.0
80.0
667
870
1160
5.7
7.4
9.8
20.5
26.7
35.4
32.9
42.7
56.7
51.3
66.5
88.4
100.0
120.0
130.0
1450
1740
1885
12.2
14.7
15.9
44.2
52.9
57.3
70.8
84.8
91.8
110.2
132.1
143.0
