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YAMADA DP-20F/P Maintenance Manual

Manual is about: YAMADA AIR-OPERATED DOUBLE DIAPHRAGM PUMP

Summary of DP-20F/P

  • Page 1

    Maintenance manual yamada air-operated double diaphragm pump dp-20f/p dp-25f/p dp-25f/c dp-38f/p dp-38f/c doc. No. Ndp403m-05.

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    Warning - for safety’s sake, be sure to read this maintenance manual thoroughly before starting maintenance for this product. After reading the manual, keep it in an easy-to-access place so that the user may refer to it whenever necessary. This maintenance manual describes the items required for mai...

  • Page 3

    Table of contents ·warnings and cautions ·table of contents 1.Principles of operation --------------------------------------------------------------- 1 2.Tools, etc. 2.1 general tools ---------------------------------------------------------------------- 1 2.2 special tools -------------------------...

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    1 fig.2.1 fig.2.2 1. Principles of operation there are two diaphragms fixed to the center rod, one at each end. When compressed air is supplied to air chamber b (right side, see fig.1.1), the center rod moves to the right, the material in material chamber b is pushed out, and at the same time materi...

  • Page 5

    2 fig.3.1 fig.3.2 fig.3.3 fig.3.4 fig.3.5 3. Balls, flat valves and valve seats 3.1 removal ▪ remove the 8 caps (4 on the top and 4 on the bottom) from both sides of the vertical tie rods. [fig.3.1] ▪ unscrew the 4 retainer nuts from the upper side of the vertical tie rods. Then, remove the reinforc...

  • Page 6

    3 fig.3.8 fig.3.9 fig.3.10 3.2 inspection ■ ball valve type ▪ ball [fig.3.6] measure the diameter, and if it is not within the permissible range, replace the ball. Permissible range of ball diameter dp-20f/p sØ 24.3 - sØ 27.8 mm dp-25f/p, dp-25f/c dp-38f/p, dp-38f/c sØ 31.5 - sØ 36.0 mm ▪ valve seat...

  • Page 7

    4 4. Diaphragm and center rod 4.1 removal ▪ remove the balls or flat valves, valve seats, valve guides, valve stoppers, etc. (see [3.1 removal]) ▪ remove the 12 caps (16 caps for dp-38f/□) from both sides of horizontal tie rods. [fig.4.1] ▪ unscrew the 12 retainer nuts (16 nuts for dp-38f/□) on the ...

  • Page 8

    5 fig.4.7 fig.4.8 ▪ hold the diaphragm and turn the bushing in the direction of the arrow to separate it from the diaphragm. [fig.4.6] 4.2 inspection ▪ diaphragm replace the diaphragm if it is worn out or damaged. Always replace both diaphragms at the same time. Guideline of diaphragm life 6 million...

  • Page 9

    6 ▪ make sure the sealing surface is not dirty or damaged. ▪ tighten the nuts evenly and alternately in a diagonal sequence to the specified torque. ▪ make sure that the directions of each coned disk spring are correct. [fig.4.11] ▪ attach the pilot valve and bushing securely. (see [5.3 installation...

  • Page 10

    7 5.3 installation for installation, see [exploded view] on the separate sheet and install in the reverse order of disassembly. ▪ the o ring on the valve seat is easily separated. Ensure that the o ring is fitted on the valve seat when attaching the valve seat to the body. ▪ insert the seat stopper ...

  • Page 11

    8 ▪ use pliers to pull out the c spool valve assembly. [fig.6.4] ▪ remove the sleeve from the valve body using the sleeve remover (special tool: part no. 713148). [fig.6.5] ＜ note＞ ▪ be careful not to damage or crack the sliding surface when pulling out the c spool valve assembly and sleeve. ▪ c spr...

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    9 6.2 inspection ▪ spool [fig.6.10] measure the outside diameter, and if it is not within the permissible range, replace the spool. Permissible range of spool diameter dp-f/p Ø 15.73 - Ø 15.80 mm dp-f/c Ø 15.77 - Ø 15.80 mm ▪ sleeve [fig.6.11] measure the inside diameter, and if it is not within the...

  • Page 13

    10 6.3 installation for installation, see [exploded view] on the separate sheet and install in the reverse order of disassembly. Tightening torque for valve body installation bolts dp-20f/p 2 n•m dp-25f/p, dp-25f/c dp-38f/p, dp-38f/c 7 n•m ▪ make sure the sealing surface is not dirty or damaged. ▪ s...

  • Page 14

    11 fig.8.1 fig.8.2 fig.8.3 8. Instructions for applying lubrication 8.1 applying lubricant to the packing ▪ apply plenty of grease to a v-groove of the packing. ＜ note＞ ▪ be careful not to produce air bubbles when applying grease. 8.2 applying lubricant to the center rod ▪ apply a small amount of gr...

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    Manufactured by yamada corporation international department no.1-3, 1-chome, minami- magome, ohta-ku, tokyo, 143-8504, japan phone : +81-(0)3-3777-0241 fax : +81-(0)3-3777-0584 201704 ndp403m.