(f) Examining and recording drawings and specifications preparatory to issuing an approval___. (g) Examining and recording drawings and specifications for each investigation of a motor, starter, or other individual explosion-proof unit considered independently of a complete machine assembly for certification____. (h) Examining and recording drawings and specifications for an extension of approval.--. (1) Examining and recording drawings and specifications for an extension of certification____. (1) No charge will be made for inspections and tests made solely for the Bureau's information. NOTE: When investigation, inspection, or testing is required to be performed at locations other than the Bureau's premises, the applicant shall reimburse the Bureau for traveling, subsistence, and incidental expenses of its representative (s) in accordance with standard Government travel regulations. Such reimbursement shall be in addition to the fee charged for investigation, inspection, or testing. Any funds deposited with the Bureau that exceed the fees required in accordance with the above charges will be refunded at the completion of the work or applied to future work, as directed by the applicant. [Sched. 2F, 30 F.R. 3754, Mar. 23, 1965] § 18.4 Application for approval of equipment.2 Before the Bureau of Mines will undertake the active investigation leading to approval of any equipment 3 the manufacturer or assembler shall make application by letter for an investigation of that equipment. This application in duplicate, accompanied by a check, bank draft, or money order payable to the U.S. Bureau of Mines to cover all necessary fees, shall be sent to the Central Experiment Station, Bureau of Mines, 4800 Forbes Avenue, Pittsburgh, Pennsylvania, 15213, together with drawings and specifications as prescribed in § 18.5. § 18.5 Drawings and specifications required. (a) The drawings and specifications shall be sufficient in number and detail 'The submission by or on behalf of a manufacturer or assembler of any type of apparatus for test implies acceptance by him of all the terms and conditions set forth in this part. 'Equipment for foreign shipment must meet the same requirements as that for domestic shipment. to identify the design fully. Drawings must be numbered and dated to facilitate identification and reference in the records. The complete rating of each motor, and the setting of overload protective devices and the capacity of all fuses, shall be specified. (b) An assembler who does not make the electrical parts for his machine shall submit a lay-out drawing (see figure 1) together with the following information, either on the drawing or attached thereto: (1) Each motor, controller, other electrical parts, and the wiring between them including conduit protection, (2) the rating of each motor, (3) the flameresistant portable cable, including gage of conductors, range of length, type (two-conductor round type G, flat twin type G, etc.), and (4) protection for the portable cable, such as circuit breaker rating, make, and current rating of trolley tap fuses (attachments for return conductor and frame ground conductor should be included). In addition, he shall submit the following information where applicable: (5) The current setting of overload relays and circuit breakers, and current rating of fuses, (6) details of insulated strain clamp for portable cable if supplied by the assembler, (7) a connection or wiring diagram if necessary to specify connections, (8) any other detail information necessary to specify properly essential features of the assembly. Specific identification of the parts must be given (by style number, drawing-list number, mechanical specification number or other data) so that they can be identified in the Bureau's records as having been investigated. A factory inspection sheet similar to the Sample Factory Inspection Sheet shown in § 18.6 must be prepared by the assembler for his use to assure that a proper inspection is made before an approval plate is attached to the machine. (c) A manufacturer who makes accessory parts of a machine shall furnish, in addition to the material and information listed in paragraph (b) of this section, the following material and information: (1) A drawing or drawings that shall specify the material and detailed dimensions of all parts (i) that make up explosion-proof enclosures made by him for units included under Class 1 (see § 18.11) and (ii) that form any portion of the joints through which flames might escape. Upon request, the manufacturer shall specify the material and dimen Trolley tap-. Rail hookFused to? amps. for 230 volts. If fused trolley tap is not used, any connection and wiring to the outer end of the cable shall be made in accordance with recognized standards of safety. The cable or circuit to the machine must have adequate fuse or other automatic circuit protection. Unless connection is in pure intake air, the trailing cable shall be connected by means provided on permissible equipment. MOTOR Frame No. 53-explosion-tested, 5 hp. 230 volts d. c. 1,150 r. p. m. Identification. No. 6 two-conductor type G flame-resistant portable cable 25' to 500' long. No. rubber-covered stranded wire if cable conductors are smaller than No. 6 Joint to be soldered, rubber-taped and FIGURE 1-Layout drawing for Manufacturing Co. sions for such other parts as the Bureau considers necessary for proper record. (2) Any other drawings found necessary to identify or explain any feature that has to be considered in determining whether a machine or parts thereof meet the requirements. For example, when a motor has a bearing of complex flamepath construction, the drawings should include a section through the bearing to show the relative position of each part in the assembly. (3) A wiring diagram. (4) If the drawings do not clearly indicate the purpose and functioning of electrical interlocks and special features in automatic or remote-control circuits, a description explaining their purpose shall be furnished. 4 (d) The following exception is made concerning the type of drawings required for squirrel-cage induction motors: In lieu of furnishing individual detailed shop drawings, the motor manufacturer may, if he wishes, supply one or more "skeleton" drawings for official record, giving essential information concerning the materials of which the parts are made, as well as dimensions and clearances at all flame paths, such as joints, bearings, and cable entrances, for the motor and its conduit box. If full detailed dimensions are not given for all parts, this drawing (or drawings) may show the assembled motor in section, but 4 Tre reason for limiting the exception to squirrel-cage induction motors is that this type of motor is nonsparking in normal operation. the section or sections must show the parts in their correct proportions and 10cation with respect to each other. A skeleton drawing shall not cover more than one motor-frame diameter. Information covering the ratings, range of voltages, speeds, and frequencies for which the motor will be available in this frame should be included on the skeleton drawing. Each frame shall have a suitable designation for purposes of reference and identification. In addition to the foregoing, detailed shop drawings will be required in connection with the initial inspection of a given motor. Such drawings will be used in making the inspection and will serve as a guide in determining whether sufficient information is given by the skeleton drawings. These detail drawings will not be officially listed or recorded. (e) The Bureau reserves the right to make periodic factory inspections of motors submitted pursuant to this paragraph, for which listed charges will be made. § 18.6 Factory inspection forms. Every manufacturer shall furnish to the Bureau a copy of the form that will be used by him in the inspection of assembled equipment at the factory. This form shall draw special attention to the wiring as well as to features that must be observed in order to make certain that explosion-proof enclosures are complete in all respects and agree with drawings filed with the Bureau. The following sample form may be used as a guide in drafting one suited to a particular machine: Ground Starter voltage Portable cable length ----- (-) Are motor covers wired and sealed? (or padlocked?) Is motor gland packed with at least 1⁄2 inch of packing along cable when compressed? Are lock washers in place on all bracket bolts? ------- -------- Are there any openings into the interior of the motor? Is air-hose conduit in good condition? Is air-hose conduit securely clamped to motor packing gland? Is air-hose conduit clamped to base securely? Is air-hose conduit clamped securely to starter packing gland? Is starter motor-cable gland properly packed? Is starter motor-cable gland secured against loosening? Is starter portable-cable gland properly packed? Is starter portable-cable gland secured against loosening? Are stuffing boxes for starter-, motor-, and portable-cable glands secured against loosening? By fillister head screw? How? Are motor-cable connections in starter tight? By headless set screw? Are the portable-cable connections in starter tight? If used, is ground connection in starter tight? Is positive conductor in portable cable connected to positive side of starter? Is negative conductor in portable cable connected to negative side of starter? Is ground conductor (if used) properly connected? Is starter portable-cable-gland strain clamp properly insulated? Does starter portable-cable-gland strain clamp hold cable firmly so as to prevent strain on terminals? Are lock washers in place on all cover bolts? Is cover-to-box flange joint tight? What size feeler can be inserted in joint (if any)? Is ungrounded power ( ) conductor in portable cable connected to trolley tap? Is grounded power () conductor in portable cable connected to ground clamp? Is frame ground () conductor (if present) of portable cable connected to ground clamp? Trolley tap make and type Fuse for trolley tap make, type, and rating Ground clamps make and type Are there any through holes into the starter compartment? 86-066 O-68-7 § 18.7 Material required for investiga tion. (a) It is not necessary to ship a completely assembled machine for the purpose of inspection and test when approval is desired. Gearing and mechanical parts, unless needed to complete explosion-proof enclosures, may be omitted. Only one motor, controller, rheostat, or other electrical unit of a given size and design need be shipped to the Central Experiment Station. (b) When the design necessitates the setting of tolerances to assure satisfactory running fits or safety of joints in explosion-proof casings, the parts submitted for test shall, if feasible, have the tolerances that give the maximum opening at the joints. Where a wide margin of tolerances (over 0.005 inch) is considered necessary by the manufacturer, the Bureau reserves the right to require test of a part under the conditions of maximum tolerance that the manufacturer wishes to use. (c) Pinion pullers and any other special tools needed in disassembling any parts for inspection or test shall be furnished with the equipment submitted. (a) The manufacturer shall arrange for, and prepay all costs of shipments of material to the Central Experiment Station, Bureau of Mines, 4800 Forbes Avenue, Pittsburgh, Pennsylvania, 15213. He shall also arrange for, and assume all costs of crating and removal of parts upon completion of the investigation. (b) Unless instructed to the contrary, manufacturers may ship parts to the Bureau for inspection and test immediately after filing application. Inspection and test usually are undertaken in the order of receipt of parts, provided that the application, fees, and drawings have been received. When requested to do so, the manufacturer shall provide a man to assist in disassembling parts for inspection and to prepare them for test by drilling and tapping them for pipe connections. He shall also assist in mounting and connecting the parts for test. § 18.10 Observers at formal investigations and demonstrations. No one shall be present during any part of the formal investigation conducted by the Bureau which leads to approval for permissibility except the necessary Government personnel, representatives of the applicant, and such other persons as may be mutually agreed upon by the applicant and the Bureau. Upon granting approval for permissibility, the Bureau will announce that such approval has been granted to the device and may thereafter conduct, from time to time in its discretion, public demonstrations of the tests conducted on the approved device. Those who attend any part of the investigation, or any public demonstration, shall be present solely as observers; the conduct of the investigation and of any public demonstration shall be controlled wholly by the Bureau's personnel. Results of chemical analyses of material and all information contained in the drawings, specifications, and instructions shall be deemed confidential and their disclosure will be appropriately safeguarded by the Bureau. § 18.11 Classification of parts. The electrical parts of a machine that may cause ignition of mine gas or coal dust are divided into three classes. These classes, together with the general type of enclosure that must be provided for the purpose of preventing ignitions, are as follows: |