HZ-20 Boundary Lubricated Bearings Manufacturers

What the HZ-20 Range Is and Where It Fits

HZ-20 bearings are boundary-lubricated plain bearings. The POM sliding layer carries the shaft while the oil pits retain a grease film that is replenished slowly during oscillation or rotation, so friction and wear stay low even when re-lubrication intervals are long. The construction replaces conventional solid bronze sleeves in many positions, reducing material cost and simplifying replacement.

The series suits normal ambient temperatures and moderate surface speeds. Typical duty is swinging or rotating motion under heavy load at low speed, which is exactly the working pattern found on rolling mill stands, commercial truck axles, brake and suspension pivots, forging machine tools, mining and engineering machinery, hydropower linkages, textile machinery and printing and dyeing equipment.

HZ-20 Product Range

We supply four standard HZ-20 variants that share the same layered structure and differ in backing material, filler colour and filler chemistry. Each can be ordered as a straight bush, a flanged bush, a thrust washer or a machined special.

Where a project needs a different balance of load, speed or environment, our wider plain bearing range covers HZ-10 self-lubricating bearings, HZ-800 bimetal composite bearing and HZ-JDB graphite copper sleeve options, so we can match the material to the duty rather than force one series into every position.

Technical Parameters

The published limits below apply to the standard HZ-20 construction and define the working envelope we use when checking an application.

• Maximum dynamic load: 70 MPa
• Maximum static load: 140 MPa
• Operating temperature: -40 °C to +120 °C
• Maximum linear speed: 2.5 m/s
• Maximum PV value: 2.8 MPa·m/s
• Friction coefficient: 0.06–0.12
• Sliding layer thickness: 0.3–0.5 mm, precision machinable to improve accuracy

Because the POM layer does not absorb water or oil, dimensions remain stable in humid or oily surroundings. The sliding layer can be supplied with oil holes or grooves so that grease can be introduced on a planned schedule where the duty requires it.

Configuration and Customization

We build HZ-20 bearings to the shaft and housing dimensions of the assembly, not only to catalogue sizes. Standard configurations include straight cylindrical bushes, flanged bushes for axial location, thrust washers for face contact, and split or machined variants for retrofit work.

• Bore, outer diameter, length and wall thickness to drawing
• Flange diameter, flange thickness and corner radii
• Oil holes, oil grooves or plain sliding surface
• Filler colour and chemistry, including Pb-free grades for environmental requirements
• Chamfers and lead-in radii for press fitting
• Machined bore or face after forming where tighter accuracy is required

Installation and Maintenance Notes

HZ-20 bearings are normally press-fitted into a machined housing. A correct interference holds the bush without crushing the POM layer, and a light grease film at assembly helps the first running-in cycles. Shaft surface finish and hardness influence service life as much as the bearing itself, so we review both when a position shows repeated wear.

Once installed, the oil pits release lubricant gradually and extend the interval between grease applications. On rolling mills this reduces refuelling frequency and simplifies replacement procedures. Where a line runs continuously, we recommend a defined inspection interval based on the actual load, speed and temperature rather than a fixed calendar schedule.

Manufacturing and Quality Approach

Zhejiang Huazhou Technology operates from Nanxun, Huzhou, with a production area of 30,000 m², more than 280 sets of special equipment and 50 automatic production lines. Our process covers coiling, punching, automatic chamfering, automatic coiling and raw material sintering, supported by a large mould inventory and more than 150 technical staff. Sample production is typically completed in three days, with daily output of 500,000 pieces.

We hold IATF 16949 automotive quality certification, national high-tech enterprise status and a quality management system certificate, and our products are used by automotive and machinery manufacturers in China and exported to Russia, Malaysia, Romania, Iraq and other markets.

Information We Use to Configure Your Solution

To prepare a proposal and quotation we need the working point and the interface, not a general description. The following inputs let us confirm the model, dimensions and any machining step.

Frequently Asked Questions

What is the difference between HZ-20 and a solid bronze bushing?

HZ-20 uses a thin steel backing with a sintered bronze interlayer and a POM sliding surface instead of solid bronze. It carries similar low-speed, medium-load duty at lower material cost, and the oil pits extend the interval between grease applications.

Can HZ-20 bearings run without any lubrication?

They are boundary-lubricated, not fully dry-running. A grease film is required, but the oil storage pits release it gradually so re-lubrication intervals are longer than for a conventional bronze sleeve.

Which filler grade should be used where lead is restricted?

HZ2B (blue) and HZ2Y (yellow) use Pb-free fillers and suit applications with environmental restrictions. HZ2X (black) uses a leaded filler and is intended for automotive chassis, forging, metallurgy and mining positions.

Can you produce non-standard sizes and flanged versions?

Yes. We machine to customer drawings, including flanged bushes, thrust washers, split bushes and special bore or flange dimensions, and we can add oil holes or grooves to suit the lubrication plan.

How quickly can samples be supplied?

Sample production is typically completed within three days of drawing confirmation. Our daily output capacity is 500,000 pieces, which supports both prototype builds and volume production orders.