Mounting Kit Namur Interface D20 Series

Actual product may differ from above image. Product details should be verified before purchase.

Used where the sealing face of the valve extends beyond the mounting surface
Options include M5, 10-24 or 10-32 bolts

Product Overview

The Automatic Valve Mounting Kit provides the hardware required to complete the mechanical interface between a NAMUR-pattern solenoid pilot valve and its target actuator or valve body when the sealing face of the solenoid valve extends beyond the standard mounting surface. The NAMUR interface, defined by VDI/VDE 3845, is the industry-standard bolt pattern for mounting solenoid pilot valves directly onto pneumatic actuators for process control applications, eliminating external tubing and reducing installation complexity.

In standard NAMUR configurations, the valve sealing face aligns flush with the actuator mounting boss. However, in D20 Series and other extended-body configurations, the valve body geometry causes the sealing face to project beyond the nominal mounting surface. Without the proper mounting kit, this offset makes it impossible to achieve correct seal compression and bolt engagement simultaneously. The Series mounting kit resolves this misalignment with the correct hardware stack-up, including the appropriate-length bolts and any required spacer or seal components.

Available in two models, the series supports the A8021-339 configuration with M5, 10-24, or 10-32 threaded bolt options, and the D20-114 kit for the D20 valve series. This flexibility allows the same mounting kit concept to serve both metric and inch-threaded actuator mounting bosses, covering the full range of pneumatic actuator manufacturers used in process control, oil and gas, power generation, and water treatment applications.

For system designers and MRO procurement teams, the series mounting kit eliminates the need to source individual hardware components separately. Each kit is assembled and supplied as a matched set to ensure dimensional correctness for the specific valve-actuator interface, reducing the risk of installation errors and the time spent sourcing individual parts.

Key Engineering Features

NAMUR Interface Compatibility - Designed to the VDI/VDE 3845 NAMUR mounting standard, ensuring mechanical compatibility with the full range of pneumatic actuators and process control valve bodies that conform to this widely adopted interface specification.
Extended Face Configuration Support - Specifically engineered for applications where the solenoid valve sealing face extends beyond the actuator mounting surface, providing the correct hardware geometry to achieve proper seal compression and bolt engagement.
Multiple Bolt Options - Available with M5, 10-24, and 10-32 bolts to match both metric and inch-threaded actuator mounting boss configurations, covering international actuator manufacturers across global installations.
Two Model Variants - Model A8021-339 serves the A8021 valve series interface requirements, while model D20-114 is configured for the Automatic Valve D20 Series solenoid pilot valve, providing exact hardware match for each application.
Complete Hardware Package - Each kit includes all required mounting hardware as a pre-matched assembly, eliminating the need to source bolts, seals, and spacers individually and reducing assembly errors.
Leak-Free Sealing Geometry - The kit hardware ensures that the O-ring or face seal between the pilot valve and actuator port is correctly seated and compressed to the specified interface sealing geometry, preventing pilot air leakage at the valve-actuator interface.
Quick Installation and Replacement - Kits are designed for fast field installation and replacement, supporting scheduled maintenance programs on process control valve actuators without extended downtime.

Technical Specifications

General Specifications

Parameter	Specification
Series	Mounting Kit - NAMUR Interface D20 Series
Models Available	A8021-339; D20-114
Interface Standard	NAMUR (VDI/VDE 3845) solenoid valve mounting interface
Application	Used where the sealing face of the valve extends beyond the mounting surface
Bolt Options	M5, 10-24, or 10-32 (metric and inch threaded configurations)
Compatible Valve Series	Automatic Valve D20 Series NAMUR pilot valves; A8021 Series valves
Kit Contents	Mounting bolts, seals, and required hardware for extended face installation
Media	Filtered compressed air; compatible with standard pneumatic actuator media

Certifications & Compliance

Certification/Standard	Detail
NAMUR Interface Compliance	Conforms to the VDI/VDE 3845 NAMUR solenoid valve mounting interface specification for dimensional compatibility with compliant actuators.
CE Compliance	Suitable for use in CE-marked valve and actuator assemblies when installed per manufacturer instructions within rated operating parameters.

Typical Applications & Industries

Process Control and Oil and Gas

Pneumatic actuated on/off and control valves in oil and gas production facilities, refineries, and petrochemical plants where NAMUR-mounted pilot valves are the standard method for instrument-grade solenoid valve installation.
Emergency shutdown (ESD) valve actuators where the solenoid pilot valve must be directly mounted to the actuator without external tubing to minimize response time and eliminate potential leak paths in the instrument air circuit.
Wellhead and pipeline control valve actuators where NAMUR pilot valve mounting is mandated by facility standards or IEC 61511 safety system design requirements.

Water and Wastewater Treatment

Large-diameter butterfly and ball valve actuators in water treatment plants and pumping stations where NAMUR-mounted solenoid pilots control actuator cycling for process flow management.
Wastewater digester gas handling systems with pneumatically actuated control valves that require direct-mount NAMUR solenoid pilot valves for compact, low-maintenance control.
Desalination plant process valve actuators using NAMUR-interface pilot valves for high-cycle isolation and control duty in corrosive seawater environments.

Power Generation

Steam and gas turbine control valve actuators where solenoid pilot valves must be directly mounted to minimize tubing and reduce the risk of instrument air leaks in high-stakes control loops.
Boiler feedwater and fuel gas control valve actuators in combined-cycle power plants requiring NAMUR-mounted pilot valves for compact installation in congested equipment areas.
Nuclear and conventional power plant process isolation valve actuators where NAMUR interface standardization simplifies maintenance and replacement procedures.

Chemical and Pharmaceutical Manufacturing

Reactor feed and product isolation valves in chemical manufacturing plants using pneumatic actuators with NAMUR-interface pilot valves for hazardous area installations.
Pharmaceutical batch process control valves with NAMUR-mounted pilot valves where hygienic design and minimal leak path design are critical for process integrity.
Solvent and chemical transfer valve actuators where NAMUR-mounted pilot valves eliminate instrument tubing runs that could create potential leak sources in classified areas.

Pulp, Paper, and Mining

Large actuator valve installations in pulp and paper mills where NAMUR-mounted pilot valves control liquor flow, steam, and process air valves in dusty, high-humidity environments.
Mining process plant pneumatic actuated valves in slurry handling and reagent dosing systems where compact NAMUR mounting reduces valve-to-actuator interface complexity.

Industrial Automation and Machinery

Machine builder applications where a pneumatic actuator manufacturer specifies NAMUR-interface solenoid pilot valve mounting as the standard control method for their actuator product line.
Fluid power system integrators specifying Automatic Valve D20 pilot valves on third-party NAMUR-compatible actuators, requiring the series kit to achieve correct installation geometry for extended face valve bodies.

Ordering and Model Number Configuration

Select the mounting kit model that corresponds to your Automatic Valve pilot valve series and the thread specification of your NAMUR actuator mounting boss.

Specify the correct bolt thread option (M5, 10-24, or 10-32) when ordering A8021-339 to match the actuator mounting boss thread specification.

Consult the actuator manufacturer technical data to confirm the NAMUR boss thread size and depth before ordering the mounting kit.

Contact Automatic Valve at (248) 474-6761 to confirm compatibility between the series mounting kit and your specific pilot valve and actuator combination.

A product catalog with dimensional details is available on the Automatic Valve website for download.

Mounting Kit Model Selection

Model Number	Description	Price (USD)	Bolt Options
A8021-339	Mounting Kit - NAMUR Interface, A8021 Series	$8.00	M5, 10-24, or 10-32
D20-114	Mounting Kit - NAMUR Interface, D20 Series	$14.25	Per D20 series specification

Accessories

Product Catalog

A product catalog is available for the series Mounting Kit. Visit automaticvalve.com/series/223-mounting-kit to access the catalog download link for dimensional drawings and detailed installation specifications.

Frequently Asked Questions (FAQ)

Q: What is the NAMUR interface and why is a mounting kit needed?

A: The NAMUR interface (VDI/VDE 3845) is an industry-standard specification for mounting solenoid pilot valves directly onto pneumatic actuators without external tubing. A mounting kit is required when the valve sealing face extends beyond the standard actuator mounting surface geometry, as in D20 Series configurations. The kit provides the correct bolt length and hardware to achieve proper seal compression and bolt engagement in this extended face arrangement.

Q: What bolt thread options are available for the A8021-339 kit?

A: The A8021-339 mounting kit is available with M5, 10-24, or 10-32 bolt options to match both metric and inch-threaded NAMUR actuator mounting bosses. Specify the correct thread when ordering to ensure compatibility.

Q: How do I determine which kit model I need?

A: The correct kit model depends on the Automatic Valve pilot valve series being installed. The A8021-339 kit is designed for A8021 Series pilot valves, while the D20-114 kit is for D20 Series pilot valves. Contact Automatic Valve at (248) 474-6761 if you are unsure which model applies to your installation.

Q: Does the mounting kit include O-rings or seals?

A: Yes, the series mounting kit includes the required seals and hardware as a complete assembly. This ensures that all interface components are dimensionally matched to the pilot valve sealing face geometry and actuator mounting port.

Q: Can I use metric-threaded actuators with inch-threaded pilot valve kits?

A: No. The bolt thread in the mounting kit must match the actuator mounting boss thread specification. Always confirm the actuator boss thread before selecting the bolt option for model A8021-339. Do not mix metric and inch hardware in the same assembly.

Q: What is the maximum pressure rating for the valve-actuator interface using this mounting kit?

A: The pressure rating of the interface is governed by the lower-rated component between the solenoid pilot valve and the pneumatic actuator. The mounting kit hardware itself is not the pressure-limiting element. Refer to the specific pilot valve and actuator datasheets for the working pressure ratings.

Q: Can the mounting kit be used with non-Automatic Valve actuators?

A: The kit is designed to the VDI/VDE 3845 NAMUR standard, making it compatible with any NAMUR-compliant actuator mounting boss of the correct thread size. Physical compatibility with the actuator boss geometry should be confirmed before installation.

Q: Is the mounting kit suitable for hazardous area (ATEX/IECEx) applications?

A: The mounting kit itself is a mechanical hardware assembly. For hazardous area applications, verify that the solenoid pilot valve being mounted carries the required ATEX or IECEx certification for the hazardous zone classification.

Q: How many mounting kits do I need per valve installation?

A: One mounting kit is required per pilot valve installation on a NAMUR-interface actuator. Order one kit per valve-actuator pair.

Q: Where can I find dimensional drawings for the series mounting kit?

A: A product catalog with dimensional details is available for download at automaticvalve.com/series/223-mounting-kit. Contact Automatic Valve at (248) 474-6761 for additional technical support.

Q: What is the typical lead time for the series mounting kit?

A: Standard inventory items typically ship within 1 to 3 business days. Contact Automatic Valve or your authorized distributor for current availability and lead time information.

Q: Can I reuse the mounting kit hardware after removing the pilot valve?

A: Inspect all hardware and seals before reuse. Bolts may be reused if they are not damaged or stripped. Seals and O-rings should be replaced with new components at each reinstallation to ensure a leak-free interface.

Installation & Maintenance Guidelines

Depressurize and lockout/tagout the actuator and associated pneumatic circuit before installing or removing any pilot valve or mounting hardware.
Verify the actuator NAMUR boss thread specification (M5, 10-24, or 10-32) before selecting and ordering the correct mounting kit bolt option.
Clean the actuator NAMUR mounting surface and pilot valve sealing face before installation. Remove any existing sealant, debris, or corrosion.
Inspect all kit components upon receipt. Do not install damaged bolts, deformed O-rings, or components showing signs of manufacturing defects.
Position the pilot valve squarely over the NAMUR boss and seat the sealing face against the actuator mounting surface before threading any bolts.
Thread all bolts by hand before applying torque to ensure even seating. Tighten bolts in a cross pattern to the torque value specified in the pilot valve installation instructions.
Do not over-torque mounting bolts. Excess clamping force can damage the seal or distort the pilot valve body.
After installation, apply instrument air at operating pressure and verify there are no leaks at the pilot valve-actuator interface using leak detection solution or ultrasonic detection.
Document the installation, including valve model, kit model, and torque values applied, in the maintenance record for the actuator.
Replace seal components in the mounting kit whenever the pilot valve is removed for inspection or maintenance.

Warranty & Global Support

Automatic Valve products are backed by a one-year warranty covering defects in material and workmanship from the date of purchase.

Technical support is available through Automatic Valve at (248) 474-6761 or via the contact form at automaticvalve.com.

Automatic Valve is a member of the ROSS Controls global family, with support resources available through ROSS Global offices worldwide.

For replacement kits, additional hardware, and compatible pilot valves, visit automaticvalve.com or contact your authorized Automatic Valve distributor.

Product Catalog - NAMUR Interface Valves: https://www.automaticvalve.com/documents/5554/NAMUR_Interface_Valves_AV-NAMUR_en.pdf

Instructions - 4-Way to 3-Way Conversion: https://www.automaticvalve.com/documents/413/NAMUR_Interface_Valves_4-Way_to_3-Way_Valve_Conversion.pdf