HDBH Series Hydraulic Dual Block & Stop Safety Valve Systems Operating Instructions (RC-HDBH-OI)
Overview
The ROSS Controls HDBH Series Hydraulic Dual Block & Stop Safety Valve System is a safety component designed and manufactured in accordance with Machinery Directive 2006/42/EC and UKCA (UK Conformity Assessed) requirements. The HDBH system achieves Category 4, PL e / SIL 3 when properly implemented into a safety control and monitoring system — the highest available safety ratings for hydraulic safety valves.
The HDBH system is comprised of two direct-solenoid-operated spool valves in a redundant design. It allows or blocks flow between the directional valve and its associated cylinder by opening both ports to permit movement, or by closing both ports to stop movement. This is a Block & Stop function — both the A and B ports are blocked simultaneously to stop cylinder motion.
The HDBH is intended for tasks that are routine, repetitive, and integral to production. Block and Stop functions are for momentary stopping of actuators — not for long-term hydraulic holding. The current HDBH model HDBHDC3BAEXA is an ISO D03 size with external monitoring, weighing 15.0 lb (6.80 kg). ROSS Controls, founded in 1921, brings over 100 years of fluid power expertise to hydraulic safety. Contact ROSS at 1-800-GET-ROSS or visit www.rosscontrols.com.
Key Features
Highest Safety Ratings: Cat. 4, PL e / SIL 3
The HDBH Series achieves Category 4, PL e per ISO 13849-1:2015 and SIL 3 when properly integrated. CE Conformity Declaration and UKCA (UK Conformity Assessed) certification are provided, confirming compliance with both EU and UK machinery safety requirements. Third-party certification is pending per the operating instructions.
Redundant Spool Valve Design
The HDBH comprises two direct-solenoid-operated spool valves. Redundancy is achieved through dual independent elements, each monitored by the external safety system. The redundant design means a single valve element failure is detected and the system is locked out before an unsafe condition can develop.
Flow Doubling In-Line Mounting Option
The HDBH can be mounted in sandwich configuration or converted to a single-line blocking valve using the Flow Doubling In-Line Mounting Kit. When configured with the In-Line Mounting Kit, both valve ports are connected in parallel to double the flow capacity while providing single-line blocking. This configuration flexibility allows the HDBH to serve a broader range of hydraulic circuit applications.
Tamper-Resistant Bracket and Safety Design
The HDBH includes a tamper-resistant bracket that helps prevent unauthorized removal or modification of the safety valve in service. Overall dimensions: approximately 10.0 inches (255 mm) in one direction, with mounting bracket and connection bar details per the dimensional drawing in the operating instructions.
Technical Specifications
Specifications from HDBH Series operating instructions (RC-HDBH-OI):
- Safety Category: Cat. 4, PL e per ISO 13849-1:2015
- Safety Integrity Level: SIL 3
- Construction Design: Redundant valve system, spool type
- ISO Valve Size: D03
- Supply Voltage: 20–32 V DC
- Voltage Ripple: ≤ 10%
- Model Number (current): HDBHDC3BAEXA
- Monitoring: External
- Weight: 15.0 lb (6.80 kg)
- Overall Dimensions: Approx. 10.0 in. (255 mm) length; 5.5 in. (140 mm) width; 4.5 in. (115 mm) height
- Tamper-Resistant Bracket: Included
- Certification: CE Conformity Declaration; UKCA (UK Conformity Assessed)
- Third-Party Certification: Pending
Applications
Hydraulic Machine Safety — Permissive Dual Block and Stop
The HDBH is a permissive safety device for hydraulic machine safety circuits. It is positioned between the directional valve and the cylinder, allowing hydraulic flow during normal operation. When the machine safety system activates (e.g., guard open, emergency stop), the HDBH closes both ports simultaneously to block flow in both directions and stop cylinder motion. The Cat. 4, PL e / SIL 3 performance satisfies the most stringent hydraulic machine safety requirements.
Routine Production Safety Interlocking
The HDBH is specifically intended for tasks that are routine, repetitive, and integral to production — such as point-of-operation guarding interlock circuits that must cycle rapidly and reliably. For maintenance tasks, full lockout/tagout procedures per applicable regulations must be followed to relieve hazardous energy and prevent unexpected startup.
Safety and Compliance Standards
- ISO 13849-1:2015 — Safety Function per ISO 13849: Category 4, PL e
- IEC 62061 — SIL 3
- Machinery Directive 2006/42/EC — CE Conformity Declaration provided
- UKCA — UK Conformity Assessed certification provided
- WARNING: Block and Stop is for momentary stopping — not long-term hydraulic holding
- Maintenance tasks require full lockout/tagout per OSHA 29 CFR 1910.147 / EN 1037
Installation and Setup Guide
Pre-Commissioning Inspection
Before commissioning, the installation must be carefully inspected by a qualified, trained professional. Verify that the technical specifications match the operating criteria of the machine and the hydraulic system. Confirm supply voltage is within the 20–32 V DC range with ≤ 10% ripple.
Mounting Configuration Selection
The HDBH can be sandwich mounted between the directional valve and manifold, or converted to in-line mounting using the optional Flow Doubling In-Line Mounting Kit. Select the mounting configuration based on the hydraulic circuit layout and required flow capacity. The In-Line Mounting Kit converts the HDBH to a single-line blocking valve with doubled flow capacity.
Safety Warnings for Operation
No maintenance work may be performed on the hydraulic system while under hydraulic pressure or with power not switched off. Before maintenance, depressurize all accumulators. Note the load pressures and any applied loads. Unusual noises, vibration, defects, or damage must be remedied immediately. Do not modify the unit in any non-authorized manner.
Why Choose ROSS Controls
ROSS Controls has been a leader in safety valve technology since 1921. The HDBH Series extends ROSS's proven redundant valve architecture to hydraulic dual block-and-stop applications, achieving Cat. 4, PL e / SIL 3 with CE and UKCA certification. ROSS offers a complete hydraulic safety valve family (HBB, HBH, HDBH, H L-O-X®) backed by global technical support. Contact ROSS at 1-800-GET-ROSS or visit www.rosscontrols.com.
Download This Document
The official HDBH Series Hydraulic Dual Block & Stop Safety Valve Systems Operating Instructions (RC-HDBH-OI) are available as a free PDF download.
PDF Download URL: https://ross-admin-global-us-east.s3.amazonaws.com/production/uploads/document_language_file/file/329/Hydraulic_Dual_Block-and-Stop_HDBH_Series_ROSS-HDBH-OI.pdf
Related Products and Resources
- HBB Series — Hydraulic Block and Bleed Safety Valve Systems
- HBH Series — Hydraulic Block & Stop Safety Valve Systems
- H L-O-X® Series — Hydraulic Lockout Valves
- ROSS Pneumatic L-O-X® Lockout Valves — energy isolation for pneumatic systems
- DM2® Series D — Pneumatic press clutch/brake safety valves (Cat. 4, PL e)
- ROSS M35 Series — Pneumatic safety exhaust double valves
Frequently Asked Questions
Q: What is the difference between HDBH and HBH?
A: Both are block and stop valves. The HDBH (Hydraulic Dual Block & Stop) is a dual spool valve system targeting Cat. 4, PL e / SIL 3 with CE and UKCA certification. The HBH targets Cat. 3, PL d. The HDBH is the higher-safety-category option for the most demanding hydraulic block-and-stop applications.
Q: What is the ISO valve size of the HDBH?
A: The current HDBH model (HDBHDC3BAEXA) is ISO D03 size.
Q: What supply voltage is required?
A: 20–32 V DC with a maximum voltage ripple of ≤ 10%.
Q: Can the HDBH be used for long-term hydraulic holding?
A: No. The HDBH uses spool-type valves with normal spool leakage. It is intended for momentary blocking and stopping of actuators in routine, repetitive production tasks. For long-term holding, incorporate PO checks, counterbalance valves, or mechanical locking devices.
Q: What certifications does the HDBH carry?
A: CE Conformity Declaration per Machinery Directive 2006/42/EC and UKCA (UK Conformity Assessed) are provided. Third-party certification (e.g., DGUV) is pending per the operating instructions.
Q: What is the Flow Doubling In-Line Mounting Kit?
A: This optional kit converts the HDBH to an in-line single-line blocking configuration. When installed, both valve ports are connected in parallel, doubling the flow capacity of the valve compared to the standard sandwich mounting configuration.
Q: Is the HDBH suitable for maintenance lockout/tagout applications?
A: No. The HDBH is designed for routine, repetitive production safety interlocking. Maintenance tasks require following full lockout/tagout procedures per OSHA 29 CFR 1910.147 or EN 1037 to relieve hazardous energy and prevent unexpected startup.
Q: What safety warnings apply to the HDBH system?
A: Key warnings: no maintenance work while under hydraulic pressure; depressurize accumulators before maintenance; note load pressures and applied loads; address unusual noises, vibration, or defects immediately; do not modify the unit in any non-authorized manner.