Step 1: Confirm the type of compensator you are using – metal, non-metal, or rubber?
Don't get started in a hurry, first find out which gods are installed on your pipes. Compensators looked similar in looks, but they were made of different materials, and their temper and temperament were far different. What do you haveMetal hose、Universal corrugated expansion jointStillCorrugated expansion joint for power station industry？ YesNon-metallic expansion joint (fabric fiber expansion joint)Stillrubber compensator？ Or the one with PTFERubber PTFE compensator？
How to distinguish? Just take a glance with your eyes: metal (such asHigh temperature axial expansion joint、External pressure single axial expansion joint) The surface is bright, hard to the touch, and usually rippled. Non-metallic (likeRectangular non-metallic expansion joint) It feels like thick cloth, soft and flanged. The rubber one is more direct, dark, elastic, and deformable when pinched. If you seeSleeve type pipe expansion jointThat's another structure-compensated by sleeve sliding. Before determining the type, don't do any maintenance actions, otherwise it will be easy to make jokes.
Step 2: Daily inspection-four-step method of seeing, listening, listening, touching and measuring
A daily stroll at work doesn't take much time, but it saves money on major repairs. Come on, do it:
- look: Eye sweep. Metallic (such asDirect buried (fully buried) type expansion joint) Any rust spots, cracks, deformations? Non-metallic (esp.Non-metallic expansion joint) Is there delamination, peeling, scratching by something? Rubber type (rubber compensator) Are there any bulging, aging and sticky?Flue gas baffle door、Desulfurization flue gas baffle doorThese with baffles, look at the sealing surface for any air leak signs.
- Listen: Prick up your ears. The compensator should not make abnormal noise during normal operation. The hissing may be air leakage, and the clicking may be bellows and guide tubes (yes, that'sexpansion joint guide tubeThat thing) collided. Two days ago, a client said hisDouble hinge expansion joint for air-cooled island vacuum pipelineOld ring, it turned out that the tie rod nut was loose.
- Touch: Touch with gloves (be careful of scalds or frostbite). Is it right to touch the surface temperature? Such asSteam pipelineOn the compensator, a certain section suddenly cools, which may be internal scaling or blockage. Feel the vibration amplitude again, and put your hand on the flange connection to feel it. If you shake badly, there is a problem.
- measure: Take a ruler and measure. Measure the installation length of the compensator and compare it with the original data. Such asCurved tube pressure balance expansion jointOrCompound hinge transverse expansion jointIf the displacement exceeds the design value, it must be adjusted quickly.
Tips:The frequency of inspection depends on the working conditions. High temperature and high pressure (power station, chemical industry) recommended once a day; Normal temperature and low pressure (ventilation, dust removal) twice a week is sufficient. Don't be lazy or overdo it, or you won't remember whether or not there has been any change.
Step 3: Regular maintenance-cleaning, lubrication, tightening and tie rod adjustment
Maintenance is not a one-time thing, it has to be stuck at a time. What should I do in three months, half a year and one year?
Cleaning (every 3 months)
Take a brush or compressed air to blow off dust and oil. Focus on cleanupMetal rectangular expansion jointThe corrugated gap, where corrosive media are most likely to be hidden. Non-metallic (e.g.Rectangular non-metallic expansion joint) Don't flush with water, wipe with a dry cloth. Rubber compensator is more delicate, don't touch oil solvents.
Lubrication (every 6 months)
The parts that need to be lubricated are mainlySleeve type pipe expansion jointA sliding surface,Rotary compensatorThe rotating parts, and variousexpansion joint tie rodThe thread of. Use molybdenum disulfide grease, don't use ordinary engine oil, it will carbonize when baked at high temperature.
Fastening (every 6 months)
Check all bolts, nuts. Focus on the flange connections, andLarge tie rod expansion jointBoth ends of the tie rod. Use a torque wrench to screw to the specified value, don't rely on the feel. Take a look by the wayexpansion joint guide tubeThe fixing bolts are loose, the thing falls off, the medium directly washes the bellows, and the life is discounted in half.
Tie rod adjustment (when required)
“How to adjust the tie rod nut of expansion joint？” I'll go straight to the steps: first confirm whether the pipe is in a cold state. Loosen the locking nut and rotate the adjustment nut so that the tie rod is in the "pre-stretched" or "pre-compressed" position-see the design drawings for details. After adjusting it, lock it tightly. Notice,Universal corrugated expansion joint、Straight pipe pressure balanced expansion jointThese have tie rods, and the displacement should be checked after adjustment. If you don't understand, just turn the standards. Don't play fool.
Step 4: Quick judgment and handling of common faults
Don't panic when the fault comes. Judge before you start. Here's a quick check list for you:
- Air/water leakage: 80% of the corrugated pipe is broken or the flange gasket fails. Metallic (likeMetal hose、PTFE-lined hose) may be fatigue cracks; Non-metallic may be fabric layer wear. Emergency treatment: Clamp it with a clamp, but it still has to be replaced. Long-term use? Don't think about it.
- abnormal noise: There is a high probability that the guide tube is loose or the tie rod nut is loose. Disassemble and see. If the guide tube falls off, re-weld or rivet it back. IfCompound straight pipe bypass pressure balanced expansion jointThe internal structure is messed up, so you have to contact the manufacturer.
- Stuck/not moving: Generally, there are debris stuck inside, or the guide structure is broken. Such asElectric plug-in insulation door、Manual plug-in insulation doorThese with plug boards, if there is any dust on the track, it has to be cleared. If you can save it, clean it directly, and if you can't save it, change it as a whole.
- Deformation/bulge: Overpressure or overtemperature. Stop the car quickly and check the operation records. LikeHigh temperature axial expansion jointIf the deformation is serious, it means that the material has exceeded the tolerance limit and is directly scrapped.
Step 5: Lifespan is up? These points tell you it's time to replace
Compensators are not perpetual motion machines, they have to retire. I've seen many customers figure to save money, hold on to use, and as a result, the pipe interface is cracked. So when should I change it? Here are a few hard indicators:
- Appearance: Metal bellows have visible cracks, penetrating corrosion holes, or wall thickness reduction exceeding the design value by 30%. Large area delamination, burning and holes appear in non-metallic expansion joints. The rubber compensator is seriously aged, sticky, bulging and bursting.
- Performance: The amount of compensation is not enough. Such asDirect buried (fully buried) type expansion jointIt should have absorbed 30mm displacement, but now it can only move 10mm. The internal bellows may have been plastically deformed, and it won't take a few days to support it.
- temporally: According to the Q&A mentioned "Service life of expansion joint"- -The design life of general metal compensator is 15-20 years, and the actual use is 8-10 years depending on the working conditions; Nonmetals have a short lifespan, 3-5 years; The rubber needs to be inspected in 2-4 years. You have to have a figure in mind, and don't endure according to the design lifespan.
In addition,Gas bellows(For example, the kind on gas pipelines) The state has a mandatory requirement: it is usually changed once every eight years. Never overdue.
Okay, after these five steps, you are basically a half-assed compensator maintenance master. If you are unsure of anything, look through the product information on our website, such asMetal expansion joint weight table、Metal hose size comparison tableCheck it against the model number. If it doesn't work, just call the manufacturer and ask it-but don't ask the nonsense of "How long can I use this?" Only by reporting the inspection data can people give you accurate advice.