Four-column hydraulic press safety instructions: Key points from mold installation to using the two-hand button

1. Pre-operation safety checks

• Equipment status check

Mandatory inspection items:

Hydraulic oil level (above the center line of the oil window, free of contamination)

Pressure gauge (zeroed, free of damage)

Electrical system (emergency stop button and limit switches functioning properly)

Four-column lubrication (grease guide rails and columns)

• Mold installation check

Installation specifications:

Mold alignment: Ensure the upper and lower mold centers are aligned to avoid uneven loading (calibrate using a dial indicator).

Tightening bolts: Use high-strength bolts (grade 8.8 or higher) and tighten them gradually in a diagonal order.

Safety blocks: Place hardwood or special blocks between the molds during commissioning to prevent accidental closing.

Prohibited operations:

Starting the machine with the molds not secured

Using deformed or cracked molds

2. Two-handed button operation specifications

Function of the two-handed button

Preventing one-handed operation: Both buttons must be pressed simultaneously to start the press to avoid hand injuries. Safety Distance: Button spacing ≥ 260mm (compliant with ISO 13851).

Correct Operation Procedure

Standard Procedure:

Press the start button simultaneously with both hands (interval ≤ 0.5 seconds).

The slide will automatically return after descending to the set position.

Do not place hands in the work area while the slide is moving.

Common Mistakes:

Using an object to press a button for single-handed operation

Continuing to operate the machine without troubleshooting delayed button response

Safety Device Verification

Daily Test: Intentionally press a button to confirm that the machine does not start.

Monthly Inspection: Check for button contact wear (if travel difference > 1mm, replace).

3. Safety Precautions During Operation

• Pressure and Speed Control

Initial Pressure: Use a low speed (≤ 10mm/s) to avoid impact.

Dwell Time: Set according to material properties (usually 1-5 seconds). Excessive hold time may cause the oil temperature to rise.

• Workpiece Placement Requirements

Center-centered placement: Off-center loads will cause uneven force on the column, accelerating wear. Thickness detection: If the workpiece height difference is greater than 5mm, a backing plate is required for adjustment.

• Abnormal Situation Handling

4. Four-column hydraulic press maintenance guide

 Daily Maintenance (Every Shift/Daily)

1. Pre-Startup Inspection

Required Inspection Items:

Hydraulic Oil Level: Observe the oil window; the oil level should remain within the marked range (±2mm).

Pressure Gauge: The needle should be zero, with no vibration or sticking.

Lubrication System: Manually fill the lubrication points (2# lithium grease is recommended).

Fastener Inspection: Focus on the anchor bolts and column nuts.

2. In-Operation Monitoring

Key Parameter Alarm Values:

Oil Temperature: Normal: 35-45°C, Alarm Value: ≥60°C.

System Pressure Fluctuation: ≤±5% of rated pressure.

Noise Level: ≤75dB (measured 1m from the machine).

3. Post-Stop Maintenance

Work Surface Cleaning: Use a brass scraper to remove metal debris.

Hydraulic System Pressure Relief: Operate the unloading valve to return the pressure gauge to zero.

Mold Maintenance: Apply anti-rust oil to contact surfaces.

Regular Maintenance (Weekly/Monthly/Quarterly)

1. Hydraulic System Maintenance

Maintenance Key Points:

Weekly: Check for leaks in pipe joints (slight moisture is permitted, but no dripping is allowed).

Monthly:

Clean the suction filter (replace immediately if the contamination indicator turns red).

Check the oil cleanliness (NAS 1638 standard ≤ Grade 9).

Quarterly:

Replace the return filter (original filter element recommended).

Check the oil viscosity (46 ± 5 cSt at 40°C).

2. Mechanical System Maintenance

Column Guide Sleeve:

Check for wear monthly (radial clearance ≤ 0.08mm).

Replace grease quarterly (grease injection pressure ≤ 3 MPa).

Slider Guide Rail:

Clean the track surface weekly (using kerosene and fine sandpaper).

Adjust the preload monthly (a 0.02-0.05mm feeler gauge should not penetrate).

3. Electrical System Maintenance

Monthly Inspection:

Relay Contact Condition (Contact Resistance ≤ 0.1Ω)

Limit Switch Sensitivity (Actuation Travel 2 ± 0.5mm)

Annual Inspection:

Motor Insulation Resistance (≥ 5MΩ, 500V Megohmmeter)

Ground Resistance (≤ 4Ω)