BURKERT 346868 Type 8640 modular valve island is designed to solve diverse and complex control problems due to its systematic modular construction and combination of pneumatic and electrical interfaces. By putting together a row of pneumatic modules with different numbers of valves, multiple valve functionalities may be realized on one valve unit. Electrical connectivity is achieved by either fieldbus interfaces, common connection (parallel connection technique), or multipin interfaces. Bodies and connection modules are made of high-quality plastic (polyamide) and are easy to assemble by means of the built-in snap connectors.

The 346868 configuration features a 19 mm width per station, utilizing Type 5470 solenoid valves. It offers a compact design, higher flexibility in the control cabinet, and simple exchange of valves.

General Technical Data

Product properties	Type 8640 (19 mm / Type 5470 configuration)
Body Material	PA (polyamide)
Seal Material	NBR
Width per station	19 mm
Manual override	Standard
Number of valve slots	Max. 24
Pressure range	2...10 bar (SKU 346868 specific: 2-8 bar)
Flow rate $Q_{Nn}$ value air	300 l/min measured at +20 °C, 6 bar pressure at valve inlet and 1 bar differential pressure
Nominal operating mode	Continuous operation (100% duty cycle)
Operating voltage	24 V DC (±10% tolerance)
Operating medium	Oil-free or lubricated compressed dry air, neutral gases (5 μm filter recommended)
Compressed air quality	ISO 8573-1: 2010, Class 7.4.4
Degree of protection	IP20 (IP65 in closed control cabinets / with cable plug)
Ambient temperature	0 °C...+ 55 °C

Structure and Description

The valves consist of a 3/2-way pilot valve (Type 6106) with different electrical connection variants, a valve body with diaphragm, seat seals, and A/B connection plates. The working ports 2 (B) / 4 (A) as well as supply connection and exhaust port 1 (P) / 3 (R) are available with internal thread, plug-in coupling, or pointed hose nipples.

Connections:

• 1: Pressure port
• 2 and 4: Working port
• 3: Exhaust port

Manual Override

To operate the valve manually, press the manual override and turn it 90° clockwise (until it stops). The manual override is locked and does not reset automatically. Only operate the manual override when the power is off.

Circuit Functions

Symbol	Description
C	3/2-way valve. In rest position, pressure port 1 (P/NC) closed, working port 2 (A/OUT) open after port 3 (R/NO).
D	3/2-way valve. In rest position, pressure port 1 (P/NO) open after working port 2 (B/OUT), port 3 (R/NC) closed.
G	4/2-way valve. In rest position, pressure port 1 (P) open after working port 2 (A), working port 4 (B) open after port 3 (R).

Installing Multiple Blocks

1. Begin installation with the connection module on the left.
2. Check modules for complete installation with 2 O-rings each. Lightly oil or grease all O-rings before engaging.
3. Engage the lower latch hooks of the module to be attached in the latch grooves of the preceding module. Make sure that the O-rings are properly seated.
4. Press the module to be locked upwards slightly and engage the upper latch hook.
5. Insert 3 O-rings into the recess on the back of the valve and ensure that the seal is properly fitted.

WARNING

Crushed O-rings and profile seals lead to leaky blocks. Fasten each valve to the base module with 2 screws. Recommended tightening torque 0.6 ±0.1 Nm.

Valve Block Installation

Standard rail installation:

• Hook the valve block with the upper groove into the standard rail (35 x 15 or 35 x 7.5 EN 50022).
• Snap the lower clamping pieces into the standard rail.
• Tighten the screws on the clamping pieces.

Wall installation:

• Fasten the valve block directly to the wall with M4 screws.

Safety Instructions

Risk of injury due to high pressure and escaping medium. Switch off the pressure before working on the device or system. Vent or drain the pipes.

Risk of injury due to electric shock. Switch off voltage before working on the device or system. Secure against reactivation. Observe any applicable accident prevention and safety regulations for electrical devices.