Send us your old parts, photos, dimensions, and operating conditions, and we'll directly adjust the materials, dimensions, and grooves to ensure stable operation.
I clearly replaced the O-ring, so why is it still leaking?
We've tried several different materials, so why is the service life still so short?
The dimensions clearly match the original specifications, so why isn't it sealing properly when installed?
Whether it’s a failure, material, operating environment, or compatibility with media/solvents, we can assess all these factors together. Send us photos of the on-site conditions, the old parts, or the equipment, and we’ll work together to pinpoint the problem.
Every decision boils down to one outcome: equipment that remains airtight, lasts longer, and is easier to maintain.
We will identify the root cause by analyzing failure traces—such as flattening, swelling, cracking, hardening, cuts, and extrusion—and cross-referencing them with the medium, temperature, pressure, and operating conditions, thereby restoring stable operation to the equipment.
We select the most suitable material from NBR, EPDM, FKM, HNBR, FFKM, and silicone based on the medium, temperature, pressure, and chemical compatibility, ensuring that the O-ring is truly suited to the operating conditions and provides stable, long-lasting performance.
We don’t just look at the inner diameter (ID) and wire diameter (CS); we also verify the tolerances, elongation, and compression to ensure the dimensions are truly compatible with the equipment, so that once installed, the fit is airtight.
We will verify the groove depth, width, compression ratio, fill ratio, and clearance to ensure that the O-ring fits the equipment structure properly and maintains a stable seal once installed.
We determine whether a backup ring is needed based on pressure, clearance, and hardness to ensure that the O-ring remains intact under high pressure, allowing the equipment to continue operating stably.
We take into account the medium, temperature, pressure, cleaning conditions, and actual operating environment to make seal life more predictable, allowing for better planning of maintenance, spare parts, and downtime.
First, determine which type of O-ring you need, then select the material based on the medium, temperature, pressure, and operating environment—only then will you choose the right specifications.
First, examine the equipment, grooves, and intended use to determine the structural requirements for the O-ring.
Suitable for the most common static sealing applications; first, verify the inner diameter, wire diameter, groove, and compression conditions.
View O-Ring Specifications →
If a larger contact area or a different groove fit is required, a square cross-section can be used instead to ensure a tighter seal.
Suitable for special groove and contact requirements
When pressure is high or the clearance is too large, adding a backup ring provides support, making the O-ring more stable and less likely to be squeezed out.
View High-Voltage Support Solutions →
If standard sizes are not suitable, we can develop custom specifications suitable for prototyping based on existing parts, drawings, dimensions, and operating conditions.
You can start with existing parts, dimensions, and drawingsEven for the same type of O-ring, the media it can withstand, the temperature range, and its service life will vary significantly depending on the material.
Common Oils and General Industrial Equipment
Oil-Resistant | General-Purpose
Water, Steam, and the Outdoor Environment
Water-resistant | Weather-resistant
High Temperatures, Oils, and Various Chemical Media
High-Temperature Resistance | Chemical Resistance
Requirements for higher temperatures and higher mechanical strength
Oil-resistant | High-temperature-resistant
Food, Medical, and Wide Temperature Ranges
Food-Grade | Temperature-Resistant
Extreme Chemical Conditions and Harsh High-Temperature Environments
Exceptional Chemical Resistance | Extreme EnvironmentsFirst, examine the actual conditions, then select materials and designs that will ensure long-term performance.
Under pressure cycling, O-rings in hydraulic cylinders, valve bodies, and pipe fittings are continuously subjected to compression and changes in clearance.
Since the pump body, valve cover, and piping come into contact with oils, solvents, acids, alkalis, and various other fluids, material compatibility is the first consideration.
Fuel, lubricants, and high-temperature environments can have a long-term impact on the elasticity and service life of rubber.
If the wrong material is selected for use with acids, alkalis, solvents, or corrosive media, O-rings may degrade rapidly within a short period of time.
CIP/SIP, steam, cleaning agents, and repeated disassembly and reassembly can accelerate the aging of seals.
Vacuum, plasma, specialty gases, and ultra-clean environments place even higher demands on material purity, chemical resistance, and outgassing characteristics.
FTIR material comparison, along with dimensional and visual inspections and material documentation, ensures that the O-rings you receive are verifiable and traceable, making it easier to integrate them into your internal quality control processes.
FTIR Material Comparison
We verified the feedstock material through spectral analysis, and it matched the specifications.
Test reports are traceable
The comparison results and inspection records are retained and can be provided upon request.
With the documentation in place, it’s easier to verify that the specifications have been met.
Material certification and compliance documentation are provided based on manufacturer or third-party documents, including requirements such as REACH, RoHS, FDA, COA, PFAS, and PFOS.
Simultaneous Verification of Dimensions and Appearance
Incoming materials undergo FTIR material verification, and their dimensions and appearance are checked simultaneously to ensure that the materials, specifications, and actual delivery match.
Ultimately, all of the above considerations boil down to the same outcome: fewer failures, more reliable seals, and easier maintenance.
The customer’s hydraulic equipment had been experiencing recurring leaks for some time. After re-evaluating the O-ring material, dimensions, and actual operating conditions, we proceeded with the necessary replacements and adjustments.
Food processing equipment must not only provide a proper seal, but the materials and compliance documentation must also be properly accounted for. Chengxin assists in selecting O-rings based on operating conditions and provides the corresponding material documentation.
In the face of high temperatures, high pressure, and extended operating conditions, we reevaluate material compatibility, compression, and groove conditions to ensure that O-rings truly meet the equipment’s requirements.
Whether it's old parts, photos, dimensions, part numbers, or operating conditions—just send us the information you have, and we'll consolidate it into specifications that can be processed in the next step.
