Sealing Systems & Seal Engineering HubSuptex • Kastaş • Polilas • ISO

ISO 3601 O-Rings, Suptex Rotary Shaft Seals and Kastaş Hydraulic Rod / Piston Seal Calculations

O-Ring Gland Conforming & Sealing Safe (ISO 3601 PASSED)

Squeeze: %22.1 | Gland Fill: %74.6 | Radial Gap g: 0.07 mm | Backup Ring: Not Required

1. O-Ring Cord & Diameter Selection

ISO 3601 / AS 568
O-Ring Inside Diameter (d₁):50 mm
5 mm100 mm250 mm

2. Operating Conditions & Gland Type

Polilas / ISO Standards
Operating System Pressure:25 bar
0 bar (Vacuum)50 bar (Backup Ring Threshold)250 bar

Recommended Surface Finish (ISO 3601-2)

Dynamic Sliding Surface:Ra 0.20 - 0.40 μm (Rz ≤ 1.6 μm)
Static Surface:Ra 0.80 - 1.60 μm (Rz ≤ 6.3 μm)
Groove Flanks / Side Walls:Ra 1.60 - 3.20 μm (Rz ≤ 10 μm)
Lead-in Chamfer Angle:15° - 20° (Burr-free)
ISO 3601 Gland Section & Deformation AnalysisW = 3.53 mm | b = 4.77 mm | H = 2.75 mm
COUNTER SURFACE (CYLINDER BORE / HOUSING) — Ra 0.4 μm15°–20° Lead-in ChamferGLAND BODY (PISTON / ROD) — ISO 3601-2Free: Ø3.53 mmO-RINGS = %22.1P = 25 bar(Fluid Pressure)b = 4.77 mm +0.10H = 2.75g = 0.07 mmR₁ = 0.4–0.8 mmISO 3601-2 RADIAL GLAND SECTIONNBR 70 Shore A (Standart Nitril - Hidrolik/Hava) | d₁ = Ø50 mm | W = Ø3.53 mmSQUEEZE%22.1GLAND FILL%74.6BACKUP RINGNOT REQ.SCALE: 1:2 | SURFACE FINISH: DYNAMIC Ra 0.2-0.4 μm / STATIC Ra 0.8-1.6 μm
Squeeze Ratio
%22.1

Target: %15-%28

Gland Fill
%74.6

Maximum: %85

Gland Depth (H)
2.75 mm

Machining Tol.: +0.05

Gland Width (b)
4.77 mm

Machining Tol.: +0.10

Extrusion Clearance Gap & Backup Ring (Engineering Criterion)

Backup Ring Not Required

At 25 bar pressure, maximum allowed radial gap is 0.28 mm. Under current operating pressure and standard H8/f7 or H7/g6 tolerances, there is no extrusion hazard.