Insulation inspection

LORUS is also used for inspection of piping that has been on supports or sleepers for some time, to see whether corrosion has developed at the contact points. But the technique can also be used for corrosion detection under insulation, inspection of pipelines at dike and road crossings, nozzle reinforcement pads or craek detection in suspension systems for railway cars. 

The degree and frequency of external inspection of equipment and piping under insulation is site specific. The API 570 Piping Inspection Code has added this note of caution The extent of a Corrosion Under Insulation Inspection program may vary depending on the local climate warmer, marine locations may require a very active program, whereas cooler, drier, mid-continent locations may not need as extensive a program. [16]... 

Electrical insulator inspection and casing testing Oxygen/acetylene welding Locating and marking pipelines... 

Pipelines are cleaned and inspected using pigs . Pigs usually have a steel body fitted with rubber cups and brushes or scrapers to remove wax and rust deposits on the pipe wall, as the pig is pumped along the pipe. Sometimes spherical pigs are used for product separation or controlling liquid hold up. In field lines handling untreated crude may have to be insulated to prevent wax formation. 

Fully Adhered. The substrate, ie, insulation, cover board, etc, that the single-ply membrane is to be attached to is either fuUy adhered or mechanically fastened to the deck. However, there are also appHcations where the membrane is adhered directly to the deck. The membrane is then adhered to the substrate. The typical method for adhering the membrane to the substrate is by applying a contact adhesive to the membrane and substrate, rolling the membrane into place, and brooming once the adhesive is ready. There are one-sided appHcations where the membrane is roUed directly into the adhesive that has been appHed to the substrate only. The membrane used in this appHcation method may be fleece-backed. FuUy adhered systems can be installed on any slope. The fuUy adhered appHcation offers a smooth surface that is easy to maintain and inspect, as weU as exceUent wind resistance on account of positive attachment. 

External corrosion can occur under insulation, especially if the weather barrier is not maintained or if the tank is operating at conditions at which condensation is likely. This form of attack is hidden and may be unnoticed for a long time. Inspection holes and plugs should... 

Equipment should be supported in such a way that it will not rest in pools of hquid or on damp insulating material. Porous insulation should be weatherproofed or otherwise protected from moisture and spills to avoid contact of the wet material with the equipment. Specifications should be sufficiently comprehensive to ensure that the desired composition or type of material will be used and the right condition of heat treatment and surface finish will be provided. Inspection during fabrication and prior to acceptance is desirable. 

Insulating flanges to be inspected and tested at intervals not exceeding one month to ensure the insulation is clean and in good condition. Resistance should be measured between the metal pipe on shore side of flange and the end of the hose or metal arm when freely suspended. The measured value should be at least 1000 ohms. 

I xtemal inspection criteria are provided by these standards for foundation and supports, anchor bolts, concrete or steel supports, guy wires, nozzles, sprinklers pipe hangers, . rouiuling coiiiiee(ions, protective coatings, insulation, and external metal surfaces. 

All storage tanks should be scheduled for inspection every few years. And on insulated tanks the insulation should finish 200 mm above the base so that checks can be made for corrosion. 

In some countries, mounding is used instead of conventional insulation. The tank is completely covered with clean sand or other clean material. Portions of the covering must be removed from time to time so that the outside of the tank can be inspected. 

Insolierung, /. insulation, insoweit, con , so far as, inasmuch as. Inspizient, m. inspector, inspizieren, v.t. inspect, instabil, a. unstable. 

Unseen corrosion can be the most damaging type of attack. Items should be designed to permit periodic inspection. This involves the provision of sufficiently large manways, the installation of inspection pits, the placing of flat-bottomed vessels on beams instead of directly onto concrete bases and the facility for removal of thermal insulation from vessel walls. 

Rail continuity bonds and negative feeders should be regularly inspected and tested, and the insulation to earth of the third rail or overhead catenary wires and the running (return) rails maintained satisfactorily. Track maintenance should include the renewal of sleepers and rail bedding material if necessary. 

The application of insulating materials is a specialist trade and justifies careful supervision and inspection. 

Inspect plating racks for loose insulation that would cause increased dragout. 

Hartford Steam Boiler Inspection and Insurance Company (HSB) insures distribution transformers for power generation utility companies. The cost to HSB when an insured transformer fails often exceeds a million dollars. The possibility of losses of this magnitude has given HSB the incentive to develop a transformer fault early detection and diagnosis program, based on chemical analysis of the transformer insulating oil. 

Replace all corroded isopentane, catalyst mix, or fire damaged lines and equipment. For carbon steel lines without an inspection history, pull all insulation before inspection. (Before startup)... 

Review the rest of the mechanical integrity program to ensure all critical equipment, piping, and pumps have acceptable integrity and an established inspection program with guidelines for repair. Include inspection and repair of fireproof insulation in the program. (By March 2002)... 

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