The previous 60 serial papers mainly focus on fixed large-scale titanium heating equipment deployed in workshops, pipelines and reaction vessels, establishing a complete full-lifecycle anti-corrosion governance system covering design, manufacturing, operation, maintenance, intelligent supervision, talent training, emergency disposal and international standardization. However, with the rapid development of modular skid-mounted chemical processing, field mobile emergency heating, on-site pilot test and portable experimental heating scenarios, a large number of mobile skid-mounted and small portable titanium heating devices have been widely applied in field oil and gas exploitation, emergency wastewater treatment, outdoor mobile pilot projects, geological exploration and field laboratory operations. Such equipment has prominent characteristics of frequent relocation, complex alternating environmental conditions, intermittent short-cycle operation, limited on-site operation and maintenance conditions and imperfect fixed monitoring infrastructure. Directly copying the anti-corrosion specifications formulated for fixed equipment often leads to either excessive high-cost redundant protection or obvious anti-corrosion loopholes induced by frequent environmental switching and irregular transportation vibration. Based on the existing theoretical framework of the 60 previous research achievements, this paper carries out supplementary targeted research on mobile skid-mounted and portable small titanium heating equipment, forms differentiated anti-corrosion technical clauses adapted to mobile service scenarios, perfects the working condition coverage of the whole technical system, and realizes the seamless expansion of the original anti-corrosion specification library from fixed industrial equipment to mobile field devices.
1. Typical Corrosion Failure Characteristics and Inducements of Mobile Titanium Heating Equipment
Different from fixed heating equipment with stable operating environment and relatively single stress form, mobile skid-mounted and portable small titanium heating devices face multiple superimposed corrosion risk factors in the whole lifecycle of factory prefabrication, road transportation, frequent site transfer, intermittent field operation and temporary idle storage, and present unique failure characteristics: First, long-distance road transportation and hoisting loading and unloading will produce continuous vibration, impact and alternating stress, which is extremely easy to induce fretting corrosion at pipeline flange connection positions, pipe clamp fixing points and equipment frame contact parts; surface passive film is repeatedly scratched by friction and collision, forming a large number of corrosion-sensitive micro-defects. In the process of cross-regional transfer, equipment will alternately experience coastal salt fog, inland dust, alpine low temperature, industrial acid gas and other complex atmospheric environments, and condensed water mixed with various corrosive pollutants adheres to the outer surface of titanium components, accelerating the occurrence of atmospheric pitting corrosion. Second, mobile equipment mostly adopts intermittent short-cycle startup operation mode, frequent cold and hot alternation easily triggers thermal shock cracking of the passive film under rapid temperature rise and fall; the field circulating medium is unstable in water quality, chloride and sulfide fluctuate greatly, and temporary pipeline dead zones are easy to form during equipment relocation and pipeline temporary docking, resulting in local medium enrichment and crevice corrosion. Restricted by field power supply and installation conditions, most mobile devices cannot be equipped with full-set online multi-parameter monitoring sensors, hidden corrosion precursor signals are difficult to capture in time, and minor corrosion defects gradually evolve into penetration leakage failures. Third, field operation and maintenance personnel have high mobility, lack long-term standardized training and fixed post competency certification; temporary pipeline docking, equipment startup and shutdown, cleaning and preservation operations often rely on empirical operation, and human-induced non-standard behaviors such as incomplete inert gas sealing, mismatched temporary sealing gaskets and no anti-vibration fastening inspection before startup occur frequently. In addition, mobile equipment often faces temporary outdoor idle storage in the field, without fixed heat preservation and rainproof facilities, and high humidity and salt deposition will cause secondary passivation failure of titanium surfaces during standby period.
2. Source Anti-Corrosion Optimization Design Specifications for Mobile Skid-Mounted Titanium Heating Equipment
The anti-corrosion design of mobile equipment needs to simultaneously consider transportation vibration resistance, cross-regional environmental adaptability and field rapid disassembly and assembly requirements, and optimize on the basis of the original fixed equipment design specifications: In terms of structural layout, the whole skid-mounted frame adopts integrated anti-vibration damping base design, all titanium heating pipelines use short-span dense support layout, each fixed point is equipped with PTFE flexible insulating liner to eliminate transportation fretting abrasion; all flange, quick connector and pipe clamp connection positions adopt anti-loosening double bolt fastening structure, and mark the standardized safe torque range on the equipment shell for field inspection reference. Avoid complex multi-bending pipeline layout, reduce pipeline dead zones prone to medium retention, and set convenient emptying and cleaning interfaces at the lowest point of the pipeline to avoid residual corrosive medium leading to crevice corrosion during equipment transfer and shutdown. In terms of material selection and surface protection, all mobile titanium components adopt high-purity titanium raw materials with strict impurity control to enhance the resistance to alternating low-temperature and atmospheric corrosion; after factory pressure test and non-destructive inspection, full chemical passivation and weather-resistant anti-corrosion coating spraying are carried out on the outer surface. For equipment used in cross-coastal and industrial polluted areas, thickened anti-salt-fog protective coating is required, and local collision-prone positions are wrapped with wear-resistant anti-collision protective sleeves to prevent passive film mechanical damage during transportation and hoisting. The sealing materials of all quick connectors must adopt reusable fluororubber gaskets resistant to high temperature, aging and chloride corrosion, and disposable ordinary rubber gaskets are prohibited for temporary field docking. Reserve lightweight monitoring and protection interface during design: preset sensor mounting ports for temperature, pressure and medium sampling, which can be quickly connected to portable detection instruments and temporary edge acquisition terminals in the field, avoiding destructive drilling transformation on site; reserve nitrogen sealing inflation and pressure detection interfaces for standby inert protection, which can realize rapid vacuum dehumidification and micro-positive pressure nitrogen sealing preservation after equipment shutdown at any operation site.
3. Standardized Operation, Transportation and On-Site Transfer Anti-Corrosion Management Specifications
Whole-process constraint is implemented in the links of factory delivery packaging, road transportation protection, on-site installation acceptance, intermittent startup operation and cross-site relocation transfer: Before factory outgoing transportation, all pipeline interfaces must be sealed with airtight anti-dust and moisture-proof sealing caps; the whole heating unit is wrapped with rain-proof, salt-proof and shock-absorbing packaging materials, and the skid base is fixed with anti-slip and anti-collision locking parts. Before loading and transportation, all fastening bolts shall be reinspected according to the calibrated torque value to prevent vibration loosening during driving; equipment shall be avoided to be transported in open trucks in coastal foggy, rainy and sandstorm weather. After arriving at the construction site, the first acceptance item is to check whether the equipment outer coating, pipeline contact position and connector have collision scratches and passive film damage; carry out full torque reinspection of all fixed fasteners and connecting parts, and repair and repaint the damaged protective coating in time before pipeline docking. Temporary pipeline layout shall avoid low-lying water accumulation and direct windward salt fog impact positions, and support and fix temporary pipelines with anti-vibration supports to prevent fluid pulsation from inducing fretting corrosion. For intermittent field startup operation, the staged low-power preheating specification for cold startup must be strictly implemented; portable water quality rapid detection equipment shall be used to regularly monitor the chloride, pH and turbidity of the circulating medium, and online sampling cleaning shall be arranged in time once scaling and suspended particle concentration exceed the standard. After each batch of production is completed, the pipeline must be emptied, flushed with deionized water and blow-dried with dry compressed air; if the equipment needs to be transferred to another site or temporarily shut down for more than 72 hours, portable nitrogen equipment shall be used to complete micro-positive pressure sealed preservation to avoid atmospheric humid pollutant erosion. When carrying out cross-regional repeated transfer, thoroughly clean the residual medium and surface salt dust inside and outside the equipment before packaging again, carry out coating integrity inspection and local repainting maintenance, and reimplement anti-vibration locking packaging protection to avoid cumulative corrosion damage caused by multiple transfers.
4. Lightweight Predictive Maintenance, Portable Inspection and Field Emergency Anti-Corrosion Disposal Scheme
Combined with the limitation of field infrastructure, a set of low-cost, easy-to-operate portable maintenance and inspection specifications are formulated for mobile heating equipment: Cancel the full-set fixed online monitoring system of fixed equipment, adopt periodic portable detection mode: regularly use handheld ultrasonic thickness gauge, portable pipe-to-soil potential tester, rapid microbial detection kit and chloride test paper to complete key parameter inspection of welding positions, pipeline vulnerable sections and fixed clamping points, and establish electronic portable maintenance archives stored in mobile terminals to realize whole-lifecycle data traceability. According to the corrosion risk grade of the field operating area, formulate differentiated maintenance cycles: coastal high-salt field equipment shall implement torque inspection and surface cleaning every 15 days, inland general industrial field equipment adopts monthly inspection cycle, and inland clean experimental sites implement quarterly regular inspection. For passive film scratch, local slight fretting abrasion and small-area coating damage found on site, adopt portable local polishing and on-site rapid chemical passivation repair technology to avoid the expansion of corrosion defects; when scaling and biofilm are accumulated in the pipeline, use portable circulating cleaning equipment with neutral chlorine-free cleaning agent for online flushing, and high-pressure impact cleaning is prohibited to prevent secondary damage to the titanium substrate. Formulate portable emergency leakage disposal procedures adapted to field conditions: each mobile equipment must be equipped with special leakage clamping fixtures, neutral leakage absorption materials, emergency isolation valves and personal protective supplies; once small-area pitting leakage occurs, quickly isolate the equipment, cut off the medium source, implement on-site temporary leakage blocking, and transfer the faulty device back to the factory for comprehensive defect detection and anti-corrosion repair; leaked corrosive medium shall be collected by portable intercepting containers to prevent soil and water environmental pollution in the field.
5. Simplified Field Personnel Competency Training and Lightweight Anti-Corrosion Archive Management Mechanism
Aiming at the characteristics of high mobility of field operation and maintenance personnel, a simplified hierarchical training and quick assessment system is formulated on the basis of the original post certification specification: All field operators must complete mobile equipment anti-corrosion basic training including transportation anti-loosening requirements, cold startup preheating operation, portable medium detection method, connector sealing specification, nitrogen standby sealing operation and leakage emergency disposal, and pass the handheld terminal online theoretical assessment plus on-site simple practical operation assessment before taking up posts. Establish a temporary training case library for mobile equipment, focusing on typical corrosion accidents such as transportation fretting abrasion, cross-regional salt deposition corrosion and field misoperation passive film damage, so that field personnel can quickly master high-risk forbidden operation behaviors. A lightweight mobile terminal electronic archive system is adopted instead of the fixed workshop server database: record equipment transfer location, transportation inspection records, field maintenance data, medium detection results, standby preservation records and fault disposal information in the mobile cloud archive synchronously; when the equipment is transferred across regions, the electronic archive is transferred together with the equipment, realizing the continuous inheritance of whole-lifecycle anti-corrosion data. After the service life of mobile equipment expires or suffers irreversible corrosion damage, standardized decontamination cleaning, residual medium harmless treatment and classified recycling of titanium components shall be carried out, and the final disposal record shall be archived to complete the closed-loop lifecycle management.
6. Classification Application Scheme for Mobile Titanium Heating Equipment under Typical Field Scenarios
表格
| Field Service Scenario | Core Mobile Corrosion Risk Points | Targeted Supplementary Anti-Corrosion Technical Measures | Lightweight Management Requirements |
|---|---|---|---|
| Offshore oil and gas field skid-mounted heating unit | Long-distance road + sea transportation vibration, high salt fog marine atmosphere, intermittent emergency startup | Integrated damping skid base, PTFE full contact anti-fretting liner, weekly portable salt residue cleaning, thickened weather-resistant anti-salt coating | Field personnel mandatory online anti-corrosion training, mobile cloud real-time archive uploading |
| Inland emergency environmental governance mobile heating device | Frequent site relocation, unstable wastewater medium quality, temporary outdoor idle storage | Quick-dismantling anti-loosening flange structure, pipeline lowest point emptying design, shutdown 72h nitrogen sealed standby protection | Monthly handheld ultrasonic thickness inspection, disposable incompatible gaskets prohibited |
| Plateau alpine geological exploration portable small heating equipment | Large temperature difference between day and night, low-temperature embrittlement risk, dust and sand particle erosion | High-purity cryogenic titanium material selection, inlet anti-scour protective sleeve, pre-transport full coating integrity inspection | Simplified cold startup three-stage preheating interlock operation specification, on-site rapid passive film damage repair process |
| Cross-regional fine chemical mobile pilot heating skid | Alternating industrial acid gas and coastal salt fog environment, frequent temporary pipeline docking | Fluororubber reusable sealing assembly, pre-delivery full torque locking inspection, each relocation surface pollutant cleaning | Portable rapid water quality detection before each startup, cross-region archive data synchronous migration |
This supplementary research takes mobile skid-mounted and portable small titanium heating equipment as the research object, makes up for the deficiency of the previous 60 serial papers mainly aiming at fixed industrial equipment, expands the applicable boundary of the full-lifecycle anti-corrosion theoretical system and specification library to field mobile operation scenarios, forms differentiated anti-corrosion technical clauses covering design optimization, transportation protection, on-site standardized operation, portable inspection and maintenance, field emergency disposal and lightweight talent archive management. Combined with the original multi-dimensional governance framework of safety, intelligence, low carbon and internationalization, the improved 61-item technical system realizes full coverage of fixed large-scale equipment, mobile skid-mounted devices and portable small heating equipment under various industrial and field working conditions, further enhances the universality, completeness and engineering practicability of the titanium heating equipment anti-corrosion governance system, and provides comprehensive technical support for the safe, reliable and low-cost application of titanium heating equipment in all conventional and emerging mobile industrial scenarios at home and abroad.
