I. Model-by-digit Explanation (D633-313B)

D633: D633 series direct-acting servo valve (DDV), NG6 (03) mounting surface

313:

3: Flow code → 75 L/min (Δp=35 bar)

1: Electronic / Frequency response → High frequency response (120–150 Hz), analog input, position closed-loop

3: Y port / Seal → With Y port (leakage), NBR seal, -20 to +80°C; T/Y port 350 bar high pressure

B: Standard type, without special coating, standard voltage version

In one sentence: D633-313B = NG6 + 75 L/min@35bar + 350bar full port high pressure + direct actuation without pilot valve + 120–150Hz high frequency response + with Y port (high-pressure return oil) + NBR seal

II. Core Parameters (Δp=35 bar)

Rated flow: 75 L/min (maximum of D633 series)

Maximum pressure: 350 bar (P/A/B/T/Y) (full port high pressure)

Hysteresis: <0.2%

Resolution: <0.1%

Frequency response (±100%): 120–150 Hz (high frequency gear, twice that of 312B)

Step response: ≈8 ms

Zero leakage: ≈0.8 L/min (210 bar)

Seal / Temperature: NBR (-20 to +80°C)

Drive: 24VDC, ±10V or 4–20mA

Filter: ISO 4406 15/12

Features: No pilot hole, extremely strong anti-pollution ability, independent of dynamic and pressure, spring alignment in case of power failure, with Y port high-pressure return oil, unique combination of high-frequency response + maximum flow for D633 series

III. Comparison of D633-313B and 312B (Key Differences) Table

Project D633-312B D633-313B

Flow rate 75 L/min 75 L/min (same)

Frequency response 60–90 Hz (standard) 120–150 Hz (high frequency)

Step response ≈ 12 ms ≈ 8 ms (fast approximately 30%)

Y port / pressure With Y, 350 bar With Y, 350 bar (same)

Positioning Large flow standard dynamic Large flow + high frequency response top-level dynamic

In one sentence: 313B = 312B's upgraded version with high frequency response, the same flow rate, dynamic doubled, D633 series dynamic ceiling

Four. Application scenarios

NG6 small installation surface, 75 L/min large flow + 350 bar full port high pressure + 120–150 Hz high frequency response

T/Y port high-pressure return oil (≤ 350 bar), Y port must leak externally

High-speed, high-response precise control: high-speed presses, dynamic bending machines, high-frequency fatigue testers, metallurgical high-speed gap control, precise injection molding high-speed injection

Installation space limited but requires extreme flow rate + top-level dynamic high-pressure system