Stencil marking

The identification of ammunition is a very complex art. It may be accomplished in any one of a number of methods such as examination of physical size, shape, color markings, stencilled markings, metal stampings, and data written on the packaging material... 

An example of this was a yellow body with a red band on the nose to denote high explosive, lyddite (Picric Acid) filled projectiles. When plaster kits were assembled to these projectiles a wide brown band was painted on the projectile nose and one narrow red band painted underneath it. In addition to the color markings, metal stamp and stencil markings were also employed for identification purposes... 

Aircraft bombs were introduced in World War I, and soon, various special purpose types were developed. Therefore, a color code was developed. Again each service (land and sea) of the major powers developed their own identification system consisting of colored bodies, colored bands, metal stampings and ink stencil markings... 

Figure 6-11. Stencil markings are used on wrought products and are usually applied during the manufacturing process.

Check the condition of the tank paint and the stenciling, markings, and labeling. 

Contents of the gas cylinder should be clearly identified. Color coding is NOT a reliable means of identification. Do not deface or remove any markings, tags, or stencil marks used for identification of contents attached by the vendor. Cylinders that do not bear a legibly written, stamped, or stenciled identification of the contents should not be used. They should be segregated and returned to the vendor as soon as possible. Caps used for valve protection should be kept on the cylinder except when the cylinder is in use. A cylinder s cap should be screwed all the way down on the cylinder s neck and should fit securely. The cap is for valve protection only. 

The simplest way to identify a specimen is to mark it with letters or numbers applied by stamping with a stencil or number punch. There is, of course, always the danger that the identification marks will be obliterated by corrosion. To guard against this, the several specimens in a test should be identified further by a record of their positions relative to each other or to their supporting device. Before specimens are taken from test their identity should be established in this manner unless inspection has already shown that the identification marks have been preserved. 

When noncontacting vibration probes are furnished in aecordance with 3.4.3.1, the rotor shaft sensing areas to be observed by radial vibration probes shall be concentric with the bearing journals. All shaft sensing areas (both radial vibration and axial position) shall be free from stencil and scribe marks or any other surface discontinuity, such as an oil hole or a keyway, for a minimum distance of one probe tip diameter on each side of the probe. These areas shall not be metallized. 

Pipe markings prescribed in API 5L shall be paint-stenciled on the Inside of the pipe however for pipe with a nominal outside diameter of 12 in. and under, marking may be either on the Inside or outside unless otherwise specified on the order If this Identification is tost or obliterated the length shall be rejected. 

Pipe shall be furnished mill coated inside and outside or bare with no lacquer or oil on either the ends or the body of the pipe, except for the necessary markings prescribed above. A light coat of clear lacquer may be sprayed over the stencil area only on bare pipe. If the pipe is coated at the mill, the internal coating shall meet the requirements of API RP 5L2 (list current revision) and the external coating shall meet the requirements of the buyer s specification. 

These should have a capital letter height of 12-20 mm, and should be restricted to two or three words. They can be produced by photo-enlargement, by stencilling, Letraset or by hand, using pencilled guidelines (but make sure that no pencil marks are visible on your finished poster). 

In the last question, the stencil was used without exception. The marks allocated to molecular representations presumably served as sufficient incentive for all students to locate their stencils and to take note of guidelines given during the contact session. 

The commercially available application templates are useful aids to the positioning of the starting points, and make it imnecessary to mark the plate directly with a lead pencil. The use of these templates goes back to the time when apphcation of samples for quantitative analysis was done by hand, and where the exact position of the spot was very important. However, modem precoated layers are more abrasion resistant than they were in the early days. Moreover, the distance apart of the spots when using application stencils is inflexible, and some proprietary stencils give a pattern of spots 5 mm apart, while with others the distance is 15 mm. 

Identification markings are stamped, embossed or stenciled on metal components and are the first aspect to seek and interpret when examining a metal product. 

Positive identification of all specimens is essential. Stenciling of samples is frequently used, and brittle materials can be notched. Identification marks should be located to minimize the likehhood of being obscured by corrosion effects or corrosion products. If stress is a critical component of service performance, stamped numbers should not be permitted to be a stress raiser or serve as a notch. 

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