Seal Installation and Storage Specifications
I. Core Installation Requirements
1. Strictly Prohibit Damaging the Sealing Surfaces or Sealing Lips on the Seal Surface
The sealing performance of flat seals relies entirely on the two upper and lower flat, smooth end faces. The end faces must be free of scratches, depressions, and burrs to ensure tight fit with the sealing surface and prevent medium leakage. The sealing effect of hydraulic seals (such as oil seals, O-rings, composite seals, etc.) depends on the lip line that fits precisely with the hole or shaft. The lip must be intact, smooth, free of tears, wear, and deformation.
These key sealing parts are made of special materials, mainly including graphite, various rubber and plastic materials (such as nitrile rubber, fluororubber, silicone rubber), fiber composites, etc. Although such materials have the characteristics of temperature resistance, corrosion resistance, aging resistance, softness and high resilience, their physical strength is low and they are easily damaged. Therefore, special protection and careful care must be given during the entire process of handling, installation and storage of seals: when handling, they should be wrapped with special tools or clean soft cloth to avoid directly grabbing the sealing surface/lip with hands; during installation, impurities and burrs in the installation position should be cleaned to avoid scratching by sharp objects; during storage, they should be placed separately to avoid contact with hard objects. Once the sealing surface or lip line is damaged, even a slight scratch will destroy the sealing integrity, leaving a leakage hidden danger at the sealing part. In severe cases, it may lead to equipment shutdown, medium waste, and even safety accidents.
2. Prohibit Forced Installation to Avoid Damaging the Prefabricated Structure
Some seals (such as packing seals, composite seals, special-shaped seals) need to be installed in special grooved stuffing boxes or installation grooves. Most of these seals and installation grooves are designed for tight fit to ensure no looseness after installation and guarantee the sealing effect. During construction, rough and brutal operation methods are strictly prohibited, and the seal must not be forced to be squeezed or smashed into the installation position - forced installation will directly damage the original prefabricated structure of the seal, leading to deformation, tearing and lip damage of the seal. It is just like breaking precast concrete and filling it into the required position, which will inevitably lose its original strength and function and cause sealing failure "disaster".
For such tight-fit seals, installation must be done carefully, meticulously and step by step: first, check whether the size and finish of the installation groove meet the requirements, and clean the impurities and burrs in the groove; second, a small amount of lubricating grease compatible with the medium (avoid using corrosive lubricants) can be applied to the seal surface and the inner wall of the installation groove to reduce installation resistance; finally, adopt the method of step-by-step embedding, gently press the seal to ensure that it is stably and completely embedded in the installation groove without distortion, wrinkles or damage.
3. Ensure Balance and Symmetry During Installation, and Do a Good Job in Follow-up Fastening
During installation, the seal must be accurately placed in a position that exactly clings to the effective sealing surface (or lip line), ensuring that the seal is completely attached to the sealing surface and installation groove, with uniform force and no offset or inclination. If the installation position is offset, it will cause uneven force on the sealing surface and excessive local pressure, which will easily accelerate the wear and aging of the seal during long-term use, and then lead to leakage.
After the system is put into use, the installation work is not over. Further observation and follow-up fastening work of the seal are also required: after starting the system, first conduct low-load and low-pressure trial operation to observe whether there is micro-leakage, abnormal heating and other conditions at the sealing part; after running for a period of time, check and fine-tune the fastening parts of the seal (such as gland, bolt) according to the working conditions to prevent the seal from loosening due to changes in working conditions (such as pressure fluctuation, temperature rise, equipment vibration) during the system operation, which will cause micro-leakage. If the micro-leakage is not handled in time, long-term accumulation will lead to seal collapse and serious leakage accidents.
II. Specifications for Idle Storage of Seals
When the seals are not in use temporarily, proper storage is the key to extending their service life and ensuring the subsequent use effect. The following 3 requirements must be strictly followed to avoid seal failure due to improper storage and inability to use normally.
1. Do a Good Job in Anti-aging Protection and Strictly Control the Storage Environment
The rubber, plastic, fiber and other materials of the seal are prone to aging under the influence of light, humidity and temperature, leading to the material becoming hard, brittle and losing elasticity, and then losing the sealing performance. Therefore, during storage, the following requirements must be met: ① Store in a dark place, avoid direct sunlight or strong ultraviolet radiation, and can be placed in a cool and ventilated warehouse. The storage container should be an opaque sealed box or packaging bag; ② Prevent moisture, the relative humidity of the warehouse should be controlled at 40%-60%, avoid mold and corrosion of the seal caused by a humid environment, and prohibit placing it on the water-accumulated, humid ground or corner; ③ Place flatly, the seal should be laid flat on a clean shelf or base plate, avoid stacking and squeezing to prevent deformation; ④ Keep away from cold and heat sources, avoid placing in high temperature (exceeding the upper limit of the material's temperature resistance), low temperature (below the lower limit of the material's temperature resistance) environment, and keep away from boilers, heating, air conditioning air outlets, refrigeration equipment, etc., to prevent thermal expansion and contraction of the material and accelerated aging.
2. Avoid Applying External Force and Keep in a Naturally Relaxed State
The sealing performance of the seal depends on its own resilience. During the idle period, it must be kept in a naturally relaxed state. Any external force (such as extrusion, bending, stretching) is strictly prohibited to avoid changing its original physical shape. It is forbidden to store the seal by winding or folding, place heavy objects on the seal, or bind the seal with ropes, iron wires, etc. - external pressure or deformation will cause permanent deformation of the seal. Even if it is installed and used later, it cannot restore the original elasticity and cannot achieve effective sealing.
3. Clear Classification and Labeling for Easy Management and Retrieval
There are many types of seals. Some seals have similar shapes but different materials, use positions, applicable standards, specifications and sizes, and purchase dates. If stored mixedly, it is easy to cause wrong retrieval, which not only affects the installation efficiency, but also may lead to sealing failure due to improper selection. Therefore, it is necessary to do a good job in classification and labeling: ① Classify and store according to shape, material, specification and size, and place different types of seals separately in special containers or shelves; ② Paste clear labels on each storage container or shelf, indicating the name of the seal, material (such as fluororubber, graphite), specification and size, use position (such as hydraulic system, pipeline interface), applicable standard (such as national standard, industry standard), purchase date, shelf life and other information; ③ Establish a storage account, record the in-out warehouse situation of the seal, check regularly, and give priority to using the seal with an earlier purchase date to avoid aging and failure due to long-term idleness.
III. Supplementary Notes
1. Before installation, check the integrity of the seal, confirm that there is no damage, aging or deformation, and the specification and size match the installation position, so as to avoid using unqualified seals;
2. During installation, it is forbidden to use sharp tools (such as screwdrivers, pliers) to directly contact the sealing surface or lip. If auxiliary installation is needed, special soft auxiliary tools should be selected;
3. After the seal is installed, clean the excess lubricant and impurities in the installation position to avoid impurities affecting the sealing effect;
4. Idle seals should be inspected regularly (it is recommended to inspect once a month). If aging, deformed or damaged seals are found, they should be cleaned in time to avoid mixing with qualified seals;
5. Seals of different materials should be stored separately to avoid chemical reactions between materials leading to damage of the seals.