SAE J1817:2018 pdf free download.( R ) Long-Stroke Air-Brake Actuator Marking.
This revision brings renewed focus on the original purpose of the document by 1) re-establishing the list of air brake actuators with the industry recognized standard stroke and 2) providing a list of the different means by which air brake actuators with stroke lengths greater than the industry recognized standard stroke can be identified.
The revision also adds reference to SAE J2899 (Brake Adjustment Limit for Air Brake Actuators) as the recognized source for brake inspection limits based on actuator rated stroke and as an additional means for stroke length identification.
1. SCOPE
This SAE Recommended Practice describes a marking system to distinguish long-stroke from standard stroke for service, parking, and combination air-brake actuators. and components. Said actuators are used for applying cam type foundation brakes by slack adjuster means.
11 Purpose
SAE J1817 establishes a uniform marking system to identify long-stroke actuators and components used in air-brake systems.
2. REFERENCES
2.1 Applicable Document
The following publications form a part of this specification to the extent specified herein. Unless otherwise indicated, the latest issue of SAE publications shall apply.
4. GENERAL
Long-stroke air-brake actuators have pushrod stroke capabilities in excess of standard stroke actuator designs. As some of these actuators are nearly identical in extenor appearance to the standard actuators, a unique marking system is needed for the purpose of identification by mechanics, inspectors, and others in the field. This marking will help assure both types of actuators are serviced correctly and that brakes are adjusted properly. Unique long-stroke actuator components are not interchangeable between actuator manufacturers nor standard actuator components.
5. REQUIREMENTS
5.1 Identification – Long-Stroke Actuators
There are four (4) methods described as follows, for differentiating long-stroke from standard stroke actuators. All longstroke actuators must have a letter code marking per 5.1.1 and 76.2 mm (3.00 inches) long-stroke actuators must use square inlet ports per 5.1.2. All long stroke actuators should incorporate at least one (1) of the other two (2) methods per 5.1.3 and 5.1.4.
5.1.1 Letter Code Marking
Marking on spring housing or service side pressure housing in accordance with SAE J2899 with letter code corresponding to air brake actuator rated stroke (see Figure 1).
5.1.2 Square Air Port and/or Pressure Cap Embossment
All 76.2 mm (3.00 inches) long-stroke actuators shall have square inlet ports. The top port of the service actuators shall have a square embossment that is clearly visible and cannot be obscured by paint or square port can be used (see Figures 1 and 2).
5.1.3 Servicing Instructions
Service instructions should be embossed or stamped on spring brake center sections or service side pressure caps. These instructions will instruct that long-stroke diaphragms are required for replacement. Numerical values shall be in mm and inches (see Figures 1 and 2).
5.1.4 Tags
A tag (typically trapezoidal) shall be secured to the service side clamp band bolts or attached/affixed to the actuator by a suitable means. The actuators rated stroke shall be embossed or otherwise readable within the trapezoidal area with numerical values in millimeters and inches. For actuators without clamp bands, the same information is to be provided in a highly visible alternative directly on the actuator (see Figures 1 and 2).
Figure 2- 76.2 mm (3.00 Inches) long-stroke actuator identification
5.2 Components unique to the long-stroke actuator shall have suitable text permanently marked on the components in order to identify them as long-stroke. Typical components might include (see Figure 3):
a. Diaphragm
b. Center secton
c. Pressure cap service chamber
d. End cap combination
e. Non-pressure housing
1. Service pushrod
5.3 Long-Stroke Air-Brake Actuator identifiers referred to in 5.1, if used, must meet test requirements per SAE Ji 469 as assembled on or as part of test units.
6. NOTES
6.1 Revision Indicator
A change bar (I) located in the left margin is for the convenience of the user in locating areas where technical revisions, not editorial changes. have been made to the previous issue of SAE J1817. An (R) symbol to the left of the document title indicates a complete revision of the document. including technical revisions. Change bars and (R) are not used in original publications1 nor in documents that contain editorial changes only.