Overview

This document details the specifications, ordering codes, mounting options, technical data, and operational guidelines for double-acting hydraulic cylinders with tie rod construction, compliant with ISO 6020 standards and designed for 160 bar nominal pressure.

1. Product Description and Specifications

• Type: Double-acting cylinders (Standard: ZI; Double rod cylinders: ZIGL on request)
• Piston Diameter Range: 25 mm to 200 mm
• Piston Rod Diameter Range: 12 mm to 140 mm
• Stroke Length: Up to 3,000 mm (dependent on buckling load)
• Pressure Ratings: Nominal pressure 160 bar; Proof pressure 240 bar
• Hydraulic Fluid: Mineral oil per DIN 51524 (HL, HPL)
• Operating Temperature: -20°C to +80°C
• Viscosity Range: 2.8 to 380 mm²/s
• Stroke Velocity: Standard 0.5 m/s
• Installation Position: Arbitrary
• Stroke Length Tolerance: +1.5 mm for piston Ø up to 63 mm; +2 mm for piston Ø from 80 mm

2. Ordering Code Structure

The model code consists of nine elements specifying cylinder type, piston rod thread, piston diameter, piston rod diameter, stroke length, mounting type, cushioning, seal quality, and piston rod mounting. Example: ZI A - 100 / 70 - 250 - MP5 - DB - A - GK 63

3. Cylinder Mounting Types

Thirteen mounting options are available, including:

• Front and rear tapped holes (MX5, MX6)
• Foot mounting (MS2)
• Self-aligning clevis (MP5)
• Fork clevis (MP1)
• Rectangular flange front/rear (ME5, ME6)
• Trunnion mounting front/rear/middle (MT1, MT2, MT4)
• Tie rod extensions front/rear/both (MX1, MX2, MX3)

4. End Position Cushioning

• Adjustable cushioning options: front (DH), rear (DV), both sides (DB)
• Option for no cushioning (--)
• Self-regulating cushioning available on request

5. Seal Versions

• Standard seal (A)
• Servo quality seal with reduced friction (B)

6. Piston Rod Mounting Options

• Self-aligning clevis (GK, GD)
• Fork clevis (GU)
• Other piston rod mountings available on request

7. Technical Data Tables

Detailed tables provide dimensions and parameters for piston diameters, piston rod diameters, push and pull forces, piston and annulus areas, thread sizes, and mounting dimensions for each piston size. These include:

• Push and pull forces calculated at 160 bar pressure
• Thread sizes for piston rods and mounting bolts
• Dimensional data for various mounting types (clevis, flange, trunnion, tie rod extensions, foot mounting)

8. Buckling Load and Piston Rod Diameter Selection

Piston rods with relatively long lengths compared to their diameter must be checked for buckling. The permissible buckling load (FK zul) is calculated using Euler's formula:

FK zul = (π² × E × I1) / (S × SK²)

• E: Elastic modulus of piston rod material (210,000 N/mm²)
• I1: Moment of inertia of piston rod cross-section (π × dK⁴ / 64)
• S: Safety factor (typically 3)
• SK: Effective buckling length depending on installation and stroke length

A diagram is provided to select the minimum piston rod diameter based on buckling length, safety factor, and maximum axial force. Example: For a max force of 60,000 N, safety factor 3.5, and buckling length 1.10 m, the minimum piston rod diameter is 40 mm.

9. Position Monitoring System

The piston position is monitored by magnet-sensitive sensors interacting with a permanent magnet embedded in the piston. Sensors are adjustable along the cylinder groove to set the switching point freely.

• Sensor type: SH
• Voltage: 24 V DC
• Max current: 250 mA
• Output: PNP circuit
• Protection class: IP67 (DIN 40050)
• Cable: 3 x 0.25 mm², length 2,500 mm
• Operating temperature: -20 to +80 °C
• LED indication

10. Construction and Components

The cylinder consists of the following main parts:

• Head, rear end, barrel
• Piston rod, piston, piston nut
• Tie rods, air-vent screw, nuts
• Cushioning bush, adapter bush, covering
• Seal kit including wiper, rod seal, piston seal, O-rings, and backup rings

11. Standards and Compliance

• Mounting dimensions and types conform to ISO 6020 and DIN 24554
• Nominal pressure: 160 bar; proof pressure: 240 bar
• Hydraulic fluid per DIN 51524

12. Additional Notes

• Cylinders with parameters outside the specified ranges are available on request.
• Other mounting and piston rod fastening options can be provided upon inquiry.
• Data provided is for product description only and not legally guaranteed characteristics.

Contact Information

Watz Hydraulik GmbH
Auweg 8, 35457 Lollar, Germany
Tel: +49 6406 9102-0
Fax: +49 6406 9102-41
Email: [email protected]
Website: www.watzhydraulik.de