SF- 1P Reciprocating motion bearings, are based on the structure of the SF-1 material, according to the special conditions a total of reciprocation and design novel formulations, its performance and foreign DD2 similar. Because it does not lead, it is in line with the environmental requirements.
Reciprocating MotionComposite StructureOilless Plain BearingDrawing Based Supply
140Dynamic load N/mm²
3.6PV limit N/mm²·m/s
280Max temp °C
Product OverviewReciprocating duty selection note
The SF-1P DD2 bushing is a composite plain bearing configured for reciprocating motion, where the lubrication film is repeatedly interrupted and rebuilt within each stroke. The construction combines a steel backing, a sintered bronze interlayer, and a PTFE based sliding layer with a formulation adjusted for short stroke oscillation and reversing direction. Dynamic load capacity reaches 140 N/mm² with a maximum PV of 3.6 N/mm²·m/s, and the friction coefficient typically falls between 0.04 and 0.18. Because reciprocating motion concentrates wear at stroke reversal points, the lining thickness and bronze interlayer porosity are controlled to maintain a continuous transfer film across the full stroke length. Bushings are produced to drawing for inner diameter, outer diameter, wall thickness, length, chamfer, and plating, and can be supplied with additional lubrication features for mixed lubrication duty.
AStroke Reversal ZonesWear concentrates at the two ends of the stroke. Lining thickness and transfer film continuity are controlled across the full stroke length.
BFilm RebuildingEach reversal interrupts the lubricant film. PTFE transfer to the shaft restores the low friction layer at the start of each stroke.
CHeat AccumulationShort strokes at high frequency raise surface temperature. The sintered bronze interlayer conducts heat away from the contact zone.
DContamination ControlReciprocating shafts draw dust into the bore. Wiper or seal provisions are recommended in dusty environments.
Core Advantages
Lining formulation adjusted for reversing motion and short stroke dutyDry running removes lubricant supply from the assemblySteel backing maintains bore geometry under reversing loadsStable friction from -200°C to 280°COptional lubrication features for mixed lubrication dutyBatch geometry control supports automated press fit
Product Characteristics
Structure: steel backing, sintered bronze, PTFE based liningFriction coefficient: 0.04 to 0.18Static load capacity: up to 250 N/mm²Dynamic load capacity: up to 140 N/mm²Maximum PV value: 3.6 N/mm²·m/s dry runningBore tolerance: ISO H7 to H8 by size class
Supply and CustomizationBushings are produced to drawing for inner diameter, outer diameter, wall thickness, length, chamfer, lubrication groove or hole positions, and surface treatment. Production batches are supported with dimensional inspection records covering bore tolerance, wall thickness variation, and lining adhesion. Prototype quantities and volume orders are both accepted, and packaging can be aligned with line side presentation.
ID: 3-300mmWall: 0.5-5mmGrooves or Holes: OptionalDocuments: On Request
Frequently Asked Questions
Reciprocating motion interrupts the lubricant film at each stroke reversal, and wear concentrates at the two ends of the stroke. The SF-1P lining formulation and interlayer structure are controlled so that a PTFE transfer film is rebuilt quickly after each reversal, reducing edge wear and friction spikes at the turning points.
Short strokes with high cycle frequency accumulate heat and load the reversal zones more heavily. For short stroke duty, the allowable PV should be reduced below the 3.6 N/mm²·m/s dry running limit. Stroke length, cycle frequency, and load should be reviewed together during selection.
Yes. The PTFE based lining is designed for dry running. In pneumatic cylinders, the lubricant present in the air supply is generally sufficient as a supplemental medium. Where the air supply is fully oil free, the dry running PV limit applies.
Recommended shaft hardness is 200 to 600 HV with surface roughness Ra 0.2 to 0.4 micrometers. A smoother finish reduces transfer film disruption. Where dust is present, a wiper or rod seal ahead of the bushing is recommended to prevent abrasive ingress.
Replace when the PTFE lining is worn through and the bronze interlayer becomes visible, when radial clearance exceeds the assembly limit, or when friction and operating noise increase noticeably. Because wear concentrates near the stroke reversal points, inspect the bore ends rather than the center.
SeriesSF-1P / DD2
StructureSteel / Bronze / PTFE
Motion TypeReciprocating
Dynamic Load140 N/mm²
CustomizationDrawing Based
Max. load
Static
250N/mm²
Very low speed
140N/mm²
Rotating oscillating
60N/mm²
Max.PV(dry running)
Short-term operation
3.6N/mm²•m/s
Continuous operation
1.8N/mm²•m/s
Temp. limit
-195℃~+280℃
Friction coefficient
0.05~0.20μ
Max. speed
Dry running
2m/s
Hydrodynamic operation
>2m/s
Thermal conductivity
42 W(m•k)-1
Coefficient of thermal expansion
11×10-⁶•K-1
Features - Design: Based on SF - 1 structure, designed for reciprocating motion - Performance: Similar to foreign DD2 - Eco - friendly: Lead - free, meets environmental needs
Applications - Machinery: For equipment with reciprocating - motion parts like engines and compressors
Zhejiang Shuangnuo Bearing Technology Co., Ltd. is China SF-1P Reciprocating Motion Composite Bushing, DD2 Oilless Plain Bearing Suppliers and Wholesale SF-1P Reciprocating Motion Composite Bushing, DD2 Oilless Plain Bearing Company, we are a manufacturer specializing in producing various self-lubricating copper alloy products using centrifugal casting, continuous casting, metal mold casting, and other processes. Its main products include brass, aluminum bronze, tin bronze, and others produced according to national standard grades. It processes and produces various solid inlaid self-lubricating bearing products on this basis
. At the same time, it uses sintering technology to produce bimetallic products and many other types of products. Since its establishment nearly 10 years ago, the company has focused on the research development, and production of various new self-lubricating bearings.
In the process of product production, our company has always insisted on independent casting production of raw materials to ensure the quality of products from the source; during the casting process, the whole process is monitored, and the finished product is tested by spectrometer three times before, in and after the furnace to confirm the material composition of the product. The national testing agency is regularly commissioned to test the material composition and mechanical properties of the product, and authoritative test reports can be provided to customers in need; the company implements integrated production from material to finished product processing and has more than 80 sets of advanced CNC machine tools, CNC lathes, machining centers, and other major equipment. The strong production capacity ensures that the material production is organized for customers for the first time, shortening the production cycle.
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Establishment
Founded in 2014, Shuangnuo has 10 years of experience in the industry.
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Advanced Equipment
Strong production capacity ensures that we can organize material production for customers as soon as possible and shorten the production cycle.
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Happy Clients
There are more than 5,000 cooperative customers around the world.