Type A sleeves

Type A sleeves simply encircle the pipeline and provide structural reinforcement of the defective area. To do this, they do not require sleeve-end fillet welds. Type B sleeves also encircle the pipeline and provide structural reinforcement, but since the ends are fillet welded to the pipeline, they can also contain pressure in the event that the defect is leaking or will eventually leak in subsequent service. The results of work at BatteUe showed that steel sleeve repairs are capable of restoring the strength of a damaged pipeline to a pressure level in excess of a pressure that corresponds to 100% of the specified minimum yield strength of the line pipe steel. The results of this work led to the widespread use of fuU-encirclement steel sleeves for pipeline... 

Composite repairs are often compared to Type B steel sleeves. As wUl be shown in this section, the applicability of composite repairs is most similar to that of Type A sleeves, whereas Type B sleeves have additional applicabUity over both composite repairs and Type A sleeves. 

Type of defect Type A sleeves Composite repairs Type B sleeves... 

In the previous section, it was shown that the applicability of Type A sleeves and composite repairs is similar and that Type B sleeves can be used where Type A sleeves and composite repairs cannot. 

One of the claimed advantages of composite repairs over steel sleeves is that their installation requires no welding to an in-service pipeline. It is clear from the previous discussion that the installation of Type A sleeves, which can serve the same purpose as composite repairs, also requires no welding to an in-service pipeline. Welds that do not contact the carrier pipe are not considered to be in-service welds according to Appendix B of API 1104 (API Standard 1104, 2005), even though longitudinal seam welds are made while the pipehne is in service. 

Figure 4.10 Type A sleeve end with hardenable sealant.

The applicability of Type A sleeves is nearly identical to that for composite repairs and their installation involves no welding to an in-service pipeline. Type B sleeves can be used where composite repairs cannot, such as for repair of defects that are 80% deep or greater, circumferentially oriented defects, leaking defects or for defects that will eventually leak (e.g., internal corrosion), and cracks. For both types of full-encirclement steel sleeve, the raw materials are relatively inexpensive, and the stiffness and long-term performance are equivalent to that of line pipe steel. 

Offensive-Defensive Grenades are so designed that, by the addn of a sleeve or similar device, the offensive design may be used as a defensive type by a fragmentation producing effect... 

Figure 2.1 Two types of connections to the outside world that were implemented on our devices. (A) A butt-end connection was established at the end of a channel at the edge of the device. A transfer capillary was aligned (x, y, z) using a sleeve in a sleeve approach. (B) A connection through the top of the device to the main channel was established using a sleeve in a sleeve approach. In this design, the alignment was preset on the plan of the device (x, y) while the alignment on the z axis (perpendicular to the device) was easily performed by hand. The inset shows the cross-section of the capillary with the main channel viewed from the bottom.

The effective area of a sleeve coupling, or bell and spigot-type joint is considered to be the area of a circle having a diameter equal to the outside diameter of the pipe. The effective area of convoluted expansion joints is determined by pressure tests, which are made by the manufacturer and published in his catalogs. The effective areas given in Table 7-18 are representative of the product of several manufacturers. 

The tubing elbows and other parts of the material line are held together by couplings, as illustrated in Fig. 7.30. This is a sleeve-type compression coupling with a neoprene gasket and stainless-steel ground strip to allow the dissipation of static electricity. 

Physeal fractures are Salter-Harris type I and II. They are avulsion type injuries. Younger children tend to sustain type I apophyseal avulsions where the fracture line may extend to the coronoid process almost like a sleeve fracture and not therefore break the articular surface (Fig. 18.19). Older children are more likely to sustain Salter-Harris type II equivalent injuries. A small metaphyseal flake of bone may be apparent on radiographs. 

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