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.
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...
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 -------------------------...
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...
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...
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...
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 ...
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...
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...
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 ...
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...
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...
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...
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...
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.