JIS-A-8915-1982-ENG.pdf

UDC 621.86/.87:624.132:531.24.083 JIS ' JAPANESE I NDUSTRIAL STANDARD Ear th-moving Machinery-Method for Locating the Centre of Gravity Printed in Japan 7s I _ JIS A 89 I 5 -1982 Translated and Published by Japanese Standards Association Copyright Japanese Standards Association Provided by IHS under license with JSALicensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/12/2007 09:09:44 MDTNo reproduction or networking permitted without license from IHS -,-,- J I S A*86115 82 = 4933b08 OU635258 CI Translation without guarantee standard in Japanese is to be evidence i n the event of any doubt arising, the original Copyright Japanese Standards Association Provided by IHS under license with JSALicensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/12/2007 09:09:44 MDTNo reproduction or networking permitted without license from IHS -,-,- UDC 621.86/.87:624.132:531.24.083 JAPANESE INDUSTRIAL STANDARD J I S Earth-moving Machinery-Method for A 8915-1982 Locating the Centre of Gravity 1. Scope This Japanese Industrial Standard specifies the method for locating the centre of gravity of the earth-moving machinery ( ') , hereinafter ref erred to as the “machine“. Note (l) The earth-moving machineries mentioned here are tractors, tractor shovels, scrapers, excavators, motor graders, dump trucks, tire rollers, vibration rollers, road rollers, etc, 2, Definitions For the purpose of this standard, the following definitions apply: (1) vertical reference plane 1 A plane which serves as a reference plane indicating the position of centre of gravity, that is generally a vertical plane through an axis of driving wheels or rear wheels (for 3 or more axles, the rearmost wheels). However, for a tractor shovel, a vertical plane through an axis of idle wheels(2) or front wheels. Note ( 2 ) The position Of the idle wheels shall be that corresponding to the grounding length prescribed in the specification. (3) ( 4 ) vertical reference plane 2 plane indicating the position of centre of gravity, that is a vertical plane intersecting vertically with the vertical reference plane 1, through the centre line of the centre distance of tracklinks, track or compacting width. A plane which serves as a reference horizontal reference plane plane, .on which a machine is to be placed. shall be such that no grouser penetration of a crawler type machine will cause. A plane which serves as a reference However, the plane horizontal fore-and- aft Co-ordinate A distance between the centre of gravity and the vertical reference plane 1.- lateral Co-ordinate in the horizontal plane A distance between the centre of gravity and the vertical reference plane 2. be taken as plus, if the centre of gravity lies on the right hand of the vertical reference plane 2 and as minus if it lies on the left hand, viewed towards advancing direction. It shall vertical Co-ordinate the horizontal reference plane. A distance between the centre of gravity and o. Applicable Standards and Corresponding International Standard: See page 9. Copyright Japanese Standards Association Provided by IHS under license with JSALicensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/12/2007 09:09:44 MDTNo reproduction or networking permitted without license from IHS -,-,- J I S A*8îL5 82 M L1933608 00635260 9 2 A 8915-1982 3. Measuring Conditions The machine shall be subjected to measurements under the following conditions. Furthermore , measurements may be made under the conditions otherwise as agreed between the parties concerned. (1) The machine shall be free from adhesion of mud, sand, etc. and partial deformation and the like, and shall be in a condition operatable normally. Quantity of the fuel shall be not less than 95 % in tank capacity, and the cooling water, lubricating oil, working oil, etc. shall respectively be the specified quantities, and the mass of operator shall not be included. (2) (3) Tools, spare tires and others shall be provided in the normal stowage positions. (4) The tire inflation-pressures shall be as specified in the manufacturer's operating instructions or, if a range of pressures is specified, generally be at the highest pressure. machines fitted with hydro-inflation tires, these shall be filled with the liquid in accordance with the manufacturer's designation. In the case of (5) The machine shall be subjected to measurement under no load condition, generally in the travel1ing.position or in the operat- ing position. However, if it is required to obtain the centres of gravity in other positions ( 3, or other loaded conditions , measure- ments may be made under respective conditions. Note (3) Details for these positions shall be specified in the standards for respective machines. 4 . Measuring Instruments The measuring instruments to be used for the measurements of centre of gravity shall be as given in the following, except for the crane, decking, knife edges, plumb rule or those having functions equal to these. (1) Levels The levels specified in JIS B 7510 or J I S B 7511. (2) Squares Those as specified in J I S B 7526 or J I S B 7534. (3) Tape Measures The tape measures of Grade 1 as specified in J I S B 7512. (4) Weighbridge The weighbridge having sufficient capacity for weighing the measuring objects shall be used, and its accuracy shall be 0.5 % FS (full scale). (5) Recording Board The recording board, a firm board with smooth surface of 600 m m or more high and 450 mm or more wide in dimen- sions, shall be attached, at right-angles with the vertical refer- ence plane 1 and horizontal reference plane, and in parallel with the vertical reference plane 2, on an appropriate place at the side of the machine. Copyright Japanese Standards Association Provided by IHS under license with JSALicensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/12/2007 09:09:44 MDTNo reproduction or networking permitted without license from IHS -,-,- J I S A*89L5 82 = 4933608 0005263 O _ _ _ _ 3 A 8915-1982 5. - Measuring Procedures 5.1 Horizontal Fore-and-Aft Co-ordinate 5.1.1 Crawler Type Machines The measuring procedures of the horizontal fore-and-aft Co-ordinate of the crawler type machines shall be as follows (see Fig. 1): . Measure the massMof the machine. However, a large scale machine or a long machine which is immeasurable at once may be measured by splitting . Measure the sum r of the mass of the knife edge B and the mass of the deck distributed to the knife edge B. Mount the machine on the deck being supported by knife edges A and B in the state of (2) so that the vertical reference plane 1 comes near the knife edge A, and measure the sum Rilof the mass of the machine and deck distributed on the knife edge B and the mass of knife edge B. Measure the distance P between the knife edges A and B and the horizontal distance a from the knife edge A to the vertical refer- ence plane 1. Calculate the mass of the machine Rldistributed to the knife edge B, and then calculate the horizontal fore-and-aft Co-ordinatesfrom the following equation: where s: horizontal fore-and-aft Co-ordinate (mm) Ri: mass of the machine distributed to the knife edge B (kg) Ri = Ri' -r where A,': sum of the mass of the machine and the deck dis- tributed to he knife edge B and the mass of the knife edge B (kg) r : sum of the mass of the knife edge B and the mass of the deck distributed to the knife edge B (kg) P : distance between the knife edges A and B (mm) M : mass of the machine (kg) a: horizontal distance from the knife edge A to the vertical reference plane 1 ( m m ) . However, for the value of a, take plus value if the knife edge A lies between the vertical reference plane 1 and the knife edge B, and take minus value if it lies outside. Using this calculated value of*, draw a perpendicular line VI through the centre of gravity on the recording board affixed to the machine. Copyright Japanese Standards Association Provided by IHS under license with JSALicensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/12/2007 09:09:44 MDTNo reproduction or networking permitted without license from IHS -,-,- J I S A*8915 82 Li933608 0005262 2 4 A 8915-1982 Fig. 1. Determination of Horizontal Fore-and-Aft Co-ordinate 3 M I Positlon of centre, 5.1.2 Wheeled Type Machines In the case of wheeled type machines it is not necessary to use deck and knife edges, masses distributed to the front axle or the rear axle, and then calculate f from the pitch of the axles. With brakes off, measure the Using this calculated value of 3 , draw a perpendicular line VI through the centre of gravity on the recording board affixed to the machine. 5.2 Vertical Co-ordinate The measuring procedures of the vertical Co-ordinate shall be as follows (see Fig. 2). In the case of the wheeled type machine, carry out measurements with breaks off, In the case.of the crawler type machines, carry out measurements moving the machine until the contacting grousers, both left and right, come above BB', or under the condition where the crawler plate is placed on the knife edge installed on BB'. Hold the suspending cable vertically so that the horizontal reaction force becomes zero. (1) Rest one end of the machine under test on the weighbridge, and suspend the other end at an angle of 15' to 25“ from the horizon. Furthermore, it should be preferable to employ a larger angle as far as possible. Measure the horizontal distance d between the grounding point of the machine or the knife edge and the suspending cable. (2) (3) Obtain the mass R,of the machine only which is distributed to the grounding point of the machine or to the knife edge, and then calculate the horizòntal distance c between the position of centre of gravity and the suspending cable from the following equation: Copyright Japanese Standards Association Provided by IHS under license with JSALicensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/12/2007 09:09:44 MDTNo reproduction or networking permitted without license from IHS -,-,- J I S A*8915 82 4933608 O005263 4 5 A 8915-1982 where c : horizontal distance between the position of centre of gravity and the suspending cable (mm) Rz: mass of only the machine distributed t o the grounding point of the machine or to the knife edge (kg) d : horizontal distance between the grounding point of the machine or the knife edge and the suspending cable (mm) M : mass of the machine (kg) ( 4 ) Using this calculation value c, draw the vertical line V, on the horizontal reference plane, which passes through the centre of gravity, on the recording board affixed t o the machine. PROBLEM HARD COL Copyright Japanese Standards Association Provided by IHS under license with JSALicensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/12/2007 09:09:44 MDTNo reproduction or networking permitted without license from IHS -,-,- J I S A*87L5 82 4733608 0005264 6 6 A 8915-1982 (5) Repeat the procedures mentioned above with suspending another end of the machine, and draw the vertical line Vson the horizontal reference plane, which passes through the centre of gravity, on the recording board. ( 6 ) Intersection of vertical lines VI, V, and Va on the recording board shall be.the position of the vertical Co-ordinate h . generally these do not intersect at one point, but form a small triangle, so that the intersection of median lines of the triangle shall be considered as the position of the vertical Co-ordinate Z. However, Fig. 2. Determination of Vertical Co-ordinate A M (Side view) Kni . - Suspending cable vertical to tion of centr r I i, I I I. d l I (pian) Copyright Japanese Standards Association Provided by IHS under license with JSALicensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/12/2007 09:09:44 MDTNo reproduction or networking permitted without license from IHS -,-,- 7 A 8915-1982 5.3 Lateral Co-ordinate in the Horizontal Plane The measuring pro- cedures of the lateral Co-ordinate in the horizontal plane shall be as follows (see Fig. 3) : (1) Measure the mass Raof the machine distributed to the left side wheel or crawler and the mass &distributed to the right side. (2) Measure the track or the centre distance Bof the tracklinks. (3) Calculate the lateral Co-ordinate in the horizontal plane 9 from the following equation: where 2: lateral Co-ordinate in the horizontal plane (mm) B : track or centre distance of the tracklinks (mm) 6 : horizontal distance between the right-side wheel or centre line of the tracklinks and the position of the centre of gravity (rnm) b=L R *B M where Ra: mass of the machine distributed t o the left-side wheel or the crawler (kg) Mi: total of the masses distributed to the left and right-side wheels or the crawlers (kg) Mi=Ra + R d where Ra: mass of the machine distributed to the right-side wheel or crawler (kg) Fig. 3. Determination of Lateral Co-ordinate in the Horizontal Plane 5 Position of (Vertical reference plane 2) centre Copyright Japanese Standards Association Provided by IHS under license with JSALicensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/12/2007 09:09:44 MDTNo reproduction or networking permitted without license from IHS -,-,- J I S A*8ïL5 82 4933608 00052bb T 8 A 8915-1982 6 . Records of Measured Results The records of the measured results shall be given by the table of records of measured results for position of centre of gravity as given in Tab le. Furthermore, the measured results of the position of centre of gravity shall be recorded with rounding-off to the minimum unit of 10 mm in accord- ance with JIS Z 8401. Table. Table of Records of Measured Results for Position of Centre of Gravity Manufacturer's name Designation of machine type No, of manufacture Chassis No. Engine No. Attachments Tire inflation- Front wheel kgf/cm2 Wa pressures Rear wheel kgf/cm*( kPa Date of test Place of test Name of person in charge of measurements Standing position of machine (position of attachment and others) Laden condition of machine Unladen Mass of machine M I Mass at left-hand side R, kg kg Mass at right-hand side RI kg kg Total mass Mi kg kg 3 mm mm % ' I mm mm h mm mm Co-ordinates of position of centre of gravit y 4 Note ( ) The value of 5 shall be + for the right-hand side of the verti- cal reference plane 2 and - for the left-hand side, viewed towards advancing direction. Remark: The unit given here in I 1 is in accordance with the Interna- tional System of Units (SI). Copyright Japanese Standards Association Provided by IHS under license with JSALicensee=IHS Employees/1111111001, Us