Back Pressure Regulator

(VDBPR Series)

Features ──────────────────────

• Designed for accurate regulation under low flow conditions.
• Diaphragm seal kit is replacement part.
• Handle and panel mounting type is standard.
• Various spring ranges are available.
• Fail safe relief function.

Technical Data ──────────────────

Temperature Range -20 to 150°F (-29 to 66°C)
Back Pressure Range 0 to 5, 15, 25, 35, 50 and 125 psig
End Connection Female NPT 1/4″

Application ────────────────────

• DK-LOK Back Pressure Regulator(VDBPR) is used to maintain a set pressure on upstream of the VDBPR.
• Applicable fluid is gas, vapor or other liquid.
• Applicable to chemical analysis of water and steam sampling system.

Operation ─────────────────────

• In the general operation, there always be a little flow from the outlet.
• If the back pressure rises above the set pressure, the diaphragm kit is lifted allowing the plug to open.
• The over pressure flows through the exhaust port until the back pressure is reduced to the set pressure.

Materials of Construction ──────────────────────

No Description Material Remark
 Stainless Steel Brass
1 Body ASTM A351 CF8M Brass Wetted Part
2 Body Seat PTFE  Wetted Part
3 Nozzle ASTM A479/A276 TYPE316  Wetted Part
4 Plug spring Stainless Steel 302  Wetted Part
5 Nozzle Retaining Nut ASTM A479/A276 TYPE316  Wetted Part
6 Pfug  ASTM A479/A276 TYPE316  Wetted Part
7 Diaphragm Assembly  Refer to Replacement Parts  Wetted Part
8 Bolts(6)   Stainless Steel
9  Range Spring   Stainless Steel 302
10  Bonnet   Aluminum
11  Spring Plug  Brass
12  Panel Nuts(2)   Stainless Steel
13  Handle Stem   ASTM A479/A276 TYPE316
14  Lock Nut   Stainless Steel
15  Handle   Nylon with Brass Insert
16  Set Screw   Stainless Steel

• Handle & Panel Mounting Type

• ” – (Minus)” Groove & No Panel Mounting Type

VDBPR  –  A  –  4N  –  T  –  S
ⓛ               ②     ③      ④     ⑤

Title Spring Range End Connection Type Body Material
DKLOK Back
Pressure Regulator
A : 0 to 5 psig           B : 0 to 25 psig
C : 0 to 50 psig        D : 0 to 125 psig
 4N : Female NPT 1/4″ Nil : Handle & Panel Mounting
T : ” – “Groove
S : Stainless Stee
B : Brass

Flow Characteristics ──────────────────────

Replacement Parts ──────────────────────

Part No No Description Material
VDBPR-DIA 7.1 Rivet Stainless Steel
7.3 Rubber Seat Viton
7.4 Rivet Plate Stainless Steel
7.5 Rivet Gland Stainless Steel

Factory Test ──────────────────────

Every back pressure regulator is factory tested for set pressure.
The test is to determine if the valve is relieving prior to reaching the desired set pressure.
The test will also confirm the valve is relieving pressure beyond the desired set pressure as well.

Cleaning ───────────────────────────

Every back pressure regulator is cleaned and packaged in accordance with the requirements of our cleaning standard of DC-01.

Safe Valve Selection ────────────────

The selection of a valve for any application or system design must be considered to ensure safe performance.
Valve function, valve rating, material compatibility, proper installation, operation and maintenance remain the sole responsibility of the system of the system designer and the user.
Dk Tech accepts no liability for any improper selection, installation, operation or maintenance.

Copyright ⓒ All Right Reserved by Filson Engineering Co.