What is the correct procedure to adjust the opening pressure on the Pressure limiting bypass valve with GW BSP, type VM80 without causing leaks or damage?

To correctly adjust the opening pressure on the Pressure limiting bypass valve with GW BSP, type VM80 without causing leaks or damage, follow these steps: 1. Prepare system and safety - Relieve system pressure and stop the pump. Ensure the hydraulic circuit is depressurized before any adjustment. - Wear appropriate PPE and have a clean drip tray and clean cloths ready. 2. Access the adjustment screw - Locate the adjustment screw (Allen key type) on the Pressure limiting bypass valve with GW BSP, type VM80. Remove any protective cap. 3. Locking nut - Loosen the counter nut slightly to allow adjustment, but do not remove it. 4. Make small adjustments - Using the correct size Allen key, turn the adjustment screw slowly and in small increments. Clockwise typically increases opening pressure; counter-clockwise decreases it. Do not force the screw beyond its travel. 5. Re-pressurize and test - Reapply system pressure gradually. Cycle the system while monitoring pressure with a calibrated gauge at the P connection. Verify the valve opens at the desired setpoint and flows correctly to T without external leakage. 6. Fine-tune and secure - If required, make further small adjustments repeating step 5 until the correct pressure is achieved. Once set, tighten the counter nut securely to lock the adjustment, taking care not to over-torque and damage threads or deform the screw. 7. Check seals and fittings - Inspect valve body, connections and sealing (NBR) for leaks at operating pressure up to the valveâs maximum of 260 bar. Ensure operating temperature is within -20Â°C to +90Â°C. Notes and cautions - Avoid rapid or large turns of the screw; this risks overshooting the setpoint or damaging internal components/seals. - Do not exceed the valveâs maximum operating pressure (260 bar) during testing. - If persistent leaks or abnormal operation occur, stop and service the valve.do not overtighten fittings or screws. Following this procedure will allow safe, accurate adjustment of the Pressure limiting bypass valve with GW BSP, type VM80 without causing leaks or damage.

How often should the Pressure limiting bypass valve with GW BSP, type VM80 be inspected and retested for proper opening pressure and sealing?

Pressure limiting bypass valve with GW BSP, type VM80 should be inspected and functionally tested at regular intervals to ensure correct opening pressure and sealing. For typical hydraulic systems with a maximum operating pressure of 260 bar and NBR seals, a common recommended schedule is: - Visual inspection and leak check: monthly to quarterly. - Functional opening-pressure test and sealing verification: every 6 months. - Full bench retest (set pressure calibration, leak-tightness, component wear): annually or after any abnormal event (overpressure, contamination, shock). Adjust intervals shorter when operating in harsh conditions (high temperature cycling, contamination, heavy duty or safety-critical applications). Record results and recalibrate/set screw as needed.

Can the Pressure limiting bypass valve with GW BSP, type VM80 be installed in series with other relief valves without affecting its set opening pressure?

Yes. the Pressure limiting bypass valve with GW BSP, type VM80 can be installed in series with other relief valves without changing its set opening pressure, provided the installation follows these conditions: - Ensure free flow between the P connections is not restricted: the VM80 is designed to allow free flow between P ports; any added series components must not create backpressure or flow restrictions upstream of the VM80 P connection. - Avoid pressure rise at the valve inlet due to downstream restrictions: if downstream piping or valves create pressure spikes or backpressure when the VM80 opens, the effective inlet pressure may shift and affect operation. Give sufficient pipe diameter and minimal flow losses. - Set each valve independently and lock settings: VM80 opening pressure is mechanically set with an Allen key and secured with a counter nut; adjust and lock each valve separately to preserve settings. - Consider cumulative system dynamics: transient events, pump pressure limits and interactions between reliefs can cause brief pressure overshoots. Use appropriate damping or sequencing if needed. - Respect ratings and materials: do not exceed VM80 maximum operating pressure (260 bar) or temperature range (-20Â°C to +90Â°C); ensure compatibility of fluid with NBR seals and materials. - Proper mounting and orientation: use the provided mounting holes and solid mounting to prevent mechanical stress that could alter adjustment. When installed with correct piping, independent adjustment and within specified limits, the Pressure limiting bypass valve with GW BSP, type VM80 will maintain its set opening pressure in series installations.

Pressure limiting bypass valve with GW BSP, type VM80

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Additional information

Material	AL – aluminum

VM80 relief valve limiting maximum oil pressure in hydraulic systems. Allows free flow of fluid between P connections. When pressure exceeds the set value, the T path opens and excess oil drains to the tank. The opening pressure value is set using a screw (adjustment with an Allen key, locked with a counter nut). Valve equipped with mounting holes. Body material: aluminum. Valve material: galvanized steel. Sealing: NBR. Maximum operating pressure: 260 bar. Operating temperature: from -20°C to +90°C.

List of product variants

Article number	Product variant name	DN	BAR	Availability	Actions
DC-VM80-00-08	VM80 relief valve with 1/2" BSP thread, 80 l/min, 5-50 bar	-	260	In stock	Enquiry
DC-VM80-00-12	VM80 relief valve with 3/4" BSP thread, 80 l/min, 5-50 bar	-	260	In stock	Enquiry
DC-VM80-10-08	VM80 relief valve with 1/2" BSP thread, 80 l/min, 30-260 bar	-	260	In stock	Enquiry
DC-VM80-10-12	VM80 relief valve with 3/4" BSP thread, 80 l/min, 30-260 bar	-	260	In stock	Enquiry

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VM80 relief valve limiting maximum oil pressure in hydraulic systems. Allows free flow of fluid between P connections. When pressure exceeds the set value, the T path opens and excess oil drains to the tank. The opening pressure value is set using a screw (adjustment with an Allen key, locked with a counter nut). Valve equipped with mounting holes. Body material: aluminum. Valve material: galvanized steel. Sealing: NBR. Maximum operating pressure: 260 bar. Operating temperature: from -20°C to +90°C.