Hydraulic Buffer Device (Control Box) YHCX Equipment Classification

1

Hydraulic Buffer Device (control box)

Hydraulic Buffer Device (control box), YHCX

Control Box Body: Carbon Steel Q235B (Welded, Anti-Corrosive Powder Coated); Internal Bracket: Alloy Steel 40Cr (Quenched and Tempered)

1. Deformation of the box body caused by impact from heavy objects in the industrial operation site; 2. Corrosion of the powder coating in humid or corrosive industrial environments, leading to base metal rust; 3. Fatigue cracking of the weld caused by long-term high-frequency vibration; 4. Damage to the box body seal caused by improper opening and closing, leading to dust and moisture intrusion.

1. Install a protective baffle around the control box to avoid direct impact from heavy objects; 2. Inspect the powder coating monthly, and touch up with matching anti-corrosive paint if peeling or rust is found; 3. Conduct non-destructive testing (NDT) of the box body welds every 6 months to check for fatigue cracks; 4. Ensure the box door is closed tightly after operation, and replace the box body seal if it becomes aging or damaged to prevent dust and moisture intrusion.

2

Handle

Handle, YHCX-05

Handle Body: Aluminum Alloy 6063-T6; Grip Sleeve: Nitrile Rubber (NBR)

1. Wear and aging of the rubber grip sleeve caused by long-term manual operation and friction; 2. Loosening of the handle connection caused by vibration; 3. Deformation of the aluminum alloy handle body caused by excessive operating force; 4. Corrosion of the aluminum alloy surface in humid environments.

1. Replace the rubber grip sleeve every 12 months or when obvious wear (such as thinning or cracking) is found; 2. Check the handle connection fasteners weekly and re-tighten if loose; 3. Standardize the operation force, avoiding excessive force exceeding the handle's rated load; 4. Clean the aluminum alloy handle body regularly and apply anti-corrosive spray to prevent oxidation.

3

Front pannel

Front pannel, YHCX-06

Cold-Rolled Steel Sheet SPCC (Surface Electrostatic Sprayed); Observation Window: Tempered Glass

1. Scratches on the sprayed surface caused by dust and debris in the environment; 2. Cracking of the tempered glass observation window caused by impact; 3. Deformation of the panel caused by uneven stress during installation; 4. Corrosion of the edge of the panel caused by moisture intrusion.

1. Clean the panel surface with a soft cloth to avoid scratching the sprayed layer; 2. Avoid collision with the observation window; replace the glass immediately if cracks are found; 3. Ensure uniform force during panel installation, using gaskets to adjust uneven stress; 4. Apply anti-rust oil to the panel edge every 3 months to prevent moisture corrosion.

4

Pannel A

Pannel A, YHCX-07

Cold-Rolled Steel Sheet SPCC (Surface Electrostatic Sprayed)

1. Wear of the sprayed surface caused by long-term contact with tools or materials; 2. Deformation of the panel caused by impact; 3. Loosening of the panel fixing screws caused by vibration, leading to unevenness; 4. Corrosion in humid or corrosive industrial environments.

1. Avoid placing tools or materials on the panel to prevent wear and impact; 2. Inspect the panel for deformation monthly; correct or replace it if necessary; 3. Check the fixing screws regularly and re-tighten if loose; use anti-loosening washers if needed; 4. Clean the panel surface regularly and re-spray the coating every 2 years to maintain anti-corrosion performance.

5

Pannel B

Pannel B, YHCX-09 B

Cold-Rolled Steel Sheet SPCC (Surface Electrostatic Sprayed)

1. Same as Panel A: sprayed surface wear, impact deformation, fixing screw loosening, and environmental corrosion; 2. Damage to the wiring holes on the panel caused by improper wiring operation.

1. Refer to the maintenance measures for Panel A for wear, deformation, loosening, and corrosion prevention; 2. Use cable glands when passing wires through the panel wiring holes to avoid scratching the wires and damaging the hole edges; 3. Inspect the wiring holes regularly for burrs and smooth them if found to prevent wire insulation damage.

1

High pressure rubber hose61-500(one end is 90°)

High pressure rubber hose61-500(one end is 90°), JB 1885-77

Inner Tube: Nitrile Rubber (NBR) (Oil-Resistant, High-Pressure Resistant); Reinforcement Layer: High-Strength Steel Wire Braid; Outer Cover: Chloroprene Rubber (CR) (Wear-Resistant, Anti-Aging)

1. Aging and cracking of the rubber layer caused by long-term contact with high-temperature hydraulic oil and air oxidation; 2. Wear of the outer cover caused by friction with surrounding metal components or ground; 3. Fatigue damage of the steel wire reinforcement layer caused by repeated high-pressure cycles; 4. Leakage at the joint caused by vibration loosening or O-ring aging; 5. Damage caused by excessive bending beyond the minimum bending radius.

1. Replace the high-pressure rubber hose every 18 months or when obvious aging (cracking, hardening) or wear is found; 2. Avoid friction between the hose and metal components or ground; use protective sleeves at easily worn positions; 3. Ensure the system pressure does not exceed the hose's rated pressure (61MPa); install a pressure relief valve to prevent overpressure; 4. Check the joint tightness weekly and replace the O-ring at the joint every 6 months; 5. Avoid excessive bending during installation and use, ensuring the bending radius is not less than 10 times the hose outer diameter.

2

Pressure gauge (0~25Mpa)

Pressure gauge (0~25Mpa), YN-60 ZT

Case: Iron (Surface Spray-Painted); Movement: Copper Alloy; Dial: Aluminum Alloy; Bourdon Tube: Phosphor Bronze

1. Damage to the Bourdon tube caused by overpressure exceeding the gauge's measurement range; 2. Vibration damage to the internal movement, leading to inaccurate readings; 3. Corrosion of the copper alloy components in humid or corrosive environments; 4. Damage to the dial and glass caused by impact; 5. Blockage of the pressure interface caused by hydraulic oil impurities.

1. Install a pressure limiting valve at the gauge inlet to prevent overpressure (set pressure not exceeding 25MPa); 2. Install a vibration damper between the gauge and the pipeline to reduce the impact of system vibration; 3. Regularly calibrate the pressure gauge every 12 months to ensure accurate readings; 4. Avoid impact on the gauge; replace the glass immediately if broken; 5. Clean the pressure interface every 3 months to remove hydraulic oil impurities; 6. In corrosive environments, use a protective cover to shield the gauge.

1

Screw M4x10

Screw M4x10, GB65-85

Carbon Steel 4.8 Grade (Zinc Plated)

1. Thread wear caused by repeated disassembly and assembly during maintenance; 2. Corrosion of the zinc plating layer in humid environments, leading to thread seizure; 3. Cross-threading caused by improper installation; 4. Loosening caused by long-term vibration; 5. Shear failure caused by excessive tightening torque.

1. Use a torque screwdriver to control the tightening torque within 1.5-2.0 N·m; avoid over-tightening; 2. Apply anti-seize lubricant to the threads before installation to reduce wear during disassembly; 3. Inspect the zinc plating layer regularly; replace the screw if severe corrosion is found; 4. Use anti-loosening washers (such as spring washers) with the screw to prevent vibration loosening; 5. Ensure the screwdriver bit matches the screw head to avoid slipping and damaging the thread.

2

Screw M6x10 (GB65-85)

Screw M6x10, GB65-85

Carbon Steel 4.8 Grade (Zinc Plated)

1. Similar to Screw M4x10: thread wear, zinc layer corrosion, cross-threading, vibration loosening, and over-tightening shear failure; 2. Deformation of the screw head caused by excessive torque.

1. Use a torque screwdriver to control the tightening torque within 4.5-5.5 N·m; 2. Refer to the maintenance measures for Screw M4x10 for wear, corrosion, cross-threading, and loosening prevention; 3. Avoid using worn screwdriver bits to prevent damaging the screw head.

3

Screw M6x10 (GB818-85)

Screw M6x10, GB818-85

Carbon Steel 4.8 Grade (Zinc Plated)

1. Same as Screw M6x10 (GB65-85); 2. Wear of the cross slot caused by long-term use, leading to difficulty in disassembly.

1. Refer to the maintenance measures for Screw M6x10 (GB65-85) for torque control, wear, corrosion, and loosening prevention; 2. Regularly inspect the cross slot for wear; replace the screw if the slot is severely worn to avoid disassembly difficulties; 3. Use a cross screwdriver with a matching specification to ensure full contact with the slot.

4

Bolt M8x20

Bolt M8x20, GB5781-86

Carbon Steel 8.8 Grade (Zinc Plated)

1. Thread wear caused by repeated disassembly; 2. Corrosion of the zinc plating layer in humid or corrosive environments; 3. Fatigue loosening caused by long-term high-frequency vibration; 4. Shear failure caused by overloading or excessive tightening torque; 5. Damage to the bolt shank caused by impact.

1. Use a torque wrench to control the tightening torque within 18-22 N·m; 2. Apply anti-seize lubricant to the threads before installation; 3. Use double nuts or lock washers to enhance anti-loosening performance; 4. Inspect the bolt for corrosion and wear monthly; replace if defects are found; 5. Avoid impact on the bolt shank; install protective sleeves if necessary.

5

Screw M8x25

Screw M8x25, GB68-85

Carbon Steel 8.8 Grade (Zinc Plated)

1. Thread wear and cross-threading caused by improper installation and disassembly; 2. Corrosion of the zinc plating layer leading to thread seizure; 3. Vibration loosening; 4. Shear failure caused by excessive torque; 5. Wear of the countersunk head caused by friction.

1. Use a torque wrench to control the tightening torque within 20-24 N·m; 2. Ensure the installation hole is countersunk properly to fit the screw head; 3. Refer to the maintenance measures for Bolt M8x20 for wear, corrosion, and loosening prevention; 4. Clean the countersunk hole before installation to remove debris, avoiding uneven force on the screw head.

6

Nut M10

Nut M10, GB6170-86

Carbon Steel 8.8 Grade (Zinc Plated)

1. Thread wear caused by repeated disassembly; 2. Corrosion of the zinc plating layer leading to thread seizure; 3. Thread stripping caused by over-tightening; 4. Loosening caused by vibration; 5. Deformation caused by impact.

1. Use a torque wrench to control the tightening torque matching the mating bolt (usually 32-36 N·m for M10 bolts); 2. Apply anti-seize lubricant to the threads; 3. Use spring washers or lock washers to prevent vibration loosening; 4. Inspect the nut for corrosion and thread damage monthly; replace if necessary; 5. Avoid impact on the nut; use a protective cover in harsh environments.

7

Nut M8

Nut M8, GB41-86

Carbon Steel 4.8 Grade (Zinc Plated)

1. Thread wear, corrosion, over-tightening thread stripping, vibration loosening, and impact deformation; 2. Poor contact with the washer caused by unevenness of the nut bearing surface.

1. Use a torque wrench to control the tightening torque within 18-22 N·m; 2. Refer to the maintenance measures for Nut M10 for wear, corrosion, and loosening prevention; 3. Ensure the nut bearing surface is flat and free of burrs; clean it before installation to ensure good contact with the washer.

8

Grower washer 8

Grower washer 8, GB93-87

Spring Steel 65Mn (Heat Treated, Zinc Plated)

1. Elastic fatigue caused by long-term compression and vibration, leading to loss of anti-loosening performance; 2. Corrosion of the zinc plating layer causing rust; 3. Deformation or breakage caused by excessive tightening torque; 4. Wear of the contact surface caused by friction.

1. Replace the grower washer every 12 months or when obvious fatigue (flattening, loss of elasticity) is found; 2. Do not use the washer beyond its elastic limit; control the tightening torque according to the matching bolt; 3. Inspect the zinc plating layer regularly; replace if severely corroded; 4. Ensure the washer is installed in the correct direction (the open end faces the nut) to ensure anti-loosening effect.

9

Washer 8

Washer 8, GB93-87

Spring Steel 65Mn (Heat Treated, Zinc Plated)

1. Same as Grower washer 8: elastic fatigue, corrosion, over-tightening deformation/breakage, and contact surface wear.

1. Refer to the maintenance measures for Grower washer 8 for replacement cycle, torque control, corrosion prevention, and correct installation; 2. Distinguish between grower washers and plain washers during installation to avoid incorrect use.

10

Copper washer

Copper washer, YHCX-02

Red Copper (T2)

1. Deformation and damage caused by excessive tightening torque; 2. Corrosion caused by long-term contact with hydraulic oil and moisture; 3. Wear of the sealing surface caused by repeated disassembly; 4. Oxidation of the copper surface leading to reduced sealing performance.

1. Control the tightening torque within the range that ensures sealing without excessive deformation (usually 10-15 N·m for matching M8 bolts); 2. Replace the copper washer every time it is disassembled to ensure sealing performance; 3. Store unused copper washers in a dry environment to prevent oxidation; 4. Clean the sealing surface of the washer and the mating part before installation to remove oil stains and debris.

1

Upper pivot shaft

Upper pivot shaft, YM-10-11-02.04

Alloy Steel 40Cr (Quenched and Tempered, Surface Nitriding)

1. Wear of the shaft surface caused by long-term rotational friction with the matching bearing/bushing; 2. Fatigue cracking caused by long-term alternating stress from rotation and vibration; 3. Corrosion of the nitrided layer in humid environments, leading to base metal rust; 4. Bending deformation caused by impact load; 5. Wear of the shaft end caused by contact with fixing components.

1. Apply lubricating grease to the shaft surface every 2 weeks to reduce rotational friction; 2. Conduct magnetic particle testing (MPT) for fatigue cracks every 6 months; replace the shaft immediately if cracks are found; 3. Inspect the nitrided layer thickness annually; re-nitriding or replacing the shaft if the thickness is less than 0.1mm; 4. Avoid impact on the pivot shaft; install a protective cover at the shaft end if necessary; 5. Check the shaft for bending deformation monthly; correct or replace it if the runout exceeds 0.02mm.

2

Below pivot shaft

Below pivot shaft, YM-10-11-02.03

Alloy Steel 40Cr (Quenched and Tempered, Surface Nitriding)

1. Same as Upper pivot shaft: rotational friction wear, fatigue cracking, nitrided layer corrosion, impact bending deformation, and shaft end wear; 2. Increased wear caused by uneven load bearing.

1. Refer to the maintenance measures for Upper pivot shaft for lubrication, crack detection, nitrided layer inspection, impact prevention, and deformation correction; 2. Ensure uniform load distribution on the lower pivot shaft; avoid single-point load bearing; 3. Check the matching clearance between the shaft and the bearing/bushing regularly; replace the bushing if the clearance exceeds 0.05mm.

3

O-ring 8x1.9

O-ring 8x1.9, GB1235-76

Nitrile Rubber (NBR) (Oil-Resistant, Temperature-Resistant ≤ 120℃)

1. Aging and hardening caused by long-term contact with high-temperature hydraulic oil and air oxidation; 2. Cracking and tearing caused by excessive compression deformation; 3. Wear caused by friction with the mating groove; 4. Damage caused by contact with sharp edges of the groove; 5. Swelling and failure caused by contact with incompatible hydraulic oil.

1. Replace the O-ring every 6 months or when obvious aging (hardening, cracking) is found; 2. Control the compression ratio within 15-25% to avoid excessive deformation; 3. Ensure the mating groove is smooth and free of sharp edges; chamfer the groove edges if necessary; 4. Use hydraulic oil compatible with NBR rubber; avoid using incompatible synthetic oils; 5. Store unused O-rings in a sealed, dark, and dry environment to avoid oxidation and contamination.

4

Straps

Straps, YHCX-01.02.00

Stainless Steel 304 (Band); Buckle: Carbon Steel (Zinc Plated)

1. Wear of the stainless steel band caused by friction with hoses or pipelines; 2. Corrosion of the zinc-plated buckle in humid environments; 3. Loosening of the buckle caused by vibration; 4. Fatigue fracture of the band caused by repeated tightening; 5. Damage caused by excessive tightening beyond the band's tensile strength.

1. Use rubber gaskets between the strap and the hose/pipeline to reduce friction; 2. Inspect the buckle for corrosion monthly; replace the strap if the buckle is severely corroded; 3. Check the strap tightness weekly and re-tighten if loose; 4. Avoid repeated tightening of the same strap; replace the strap if the band shows signs of fatigue (such as deformation); 5. Control the tightening force to avoid exceeding the strap's rated tensile strength.

5

Pin connector &protecting cap NPT1

Pin connector &protecting cap NPT1, P25.13 SP25.03

Connector Body: Carbon Steel (Zinc Plated); Sealing Ring: Nitrile Rubber (NBR); Protecting Cap: Polypropylene (PP)

1. Leakage caused by aging of the sealing ring; 2. Corrosion of the zinc-plated connector body in humid or corrosive environments; 3. Thread wear caused by repeated disassembly; 4. Damage to the protecting cap caused by impact or aging; 5. Loosening of the connector caused by vibration.

1. Replace the sealing ring every 6 months; 2. Apply anti-seize lubricant to the threads before installation; 3. Check the connector tightness weekly and re-tighten if loose; 4. Keep the protecting cap installed when the connector is not in use to prevent dust and moisture intrusion; 5. Replace the protecting cap if it is cracked or damaged; 6. In corrosive environments, apply anti-corrosive spray to the connector body.

6

Pin connector &protecting cap NPT1/4

Pin connector &protecting cap NPT1/4, P06.13 SP06.03

Connector Body: Carbon Steel (Zinc Plated); Sealing Ring: Nitrile Rubber (NBR); Protecting Cap: Polypropylene (PP)

1. Same as Pin connector &protecting cap NPT1: sealing ring aging, connector corrosion, thread wear, protecting cap damage, and vibration loosening; 2. Thread damage caused by improper use of tools during installation.

1. Refer to the maintenance measures for Pin connector &protecting cap NPT1 for sealing ring replacement, lubrication, tightness check, and protecting cap maintenance; 2. Use a wrench with a matching specification to avoid damaging the thread during installation and disassembly.

7

Pin connector &protecting cap NPT3/8

Pin connector &protecting cap NPT3/8, P10.13 SP10.03

Connector Body: Carbon Steel (Zinc Plated); Sealing Ring: Nitrile Rubber (NBR); Protecting Cap: Polypropylene (PP)

1. Same as Pin connector &protecting cap NPT1.

1. Refer to the maintenance measures for Pin connector &protecting cap NPT1 for all maintenance items.

8

Pin connector &protecting cap NPT3/4

Pin connector &protecting cap NPT3/4, P20.13 SP20.03

Connector Body: Carbon Steel (Zinc Plated); Sealing Ring: Nitrile Rubber (NBR); Protecting Cap: Polypropylene (PP)

1. Same as Pin connector &protecting cap NPT1; 2. Increased stress on the connector caused by improper pipeline support, leading to deformation.

1. Refer to the maintenance measures for Pin connector &protecting cap NPT1 for sealing ring replacement, lubrication, tightness check, and protecting cap maintenance; 2. Install pipeline supports near the connector to reduce stress on the connector body.