YAMADA NDP-5, NDP-15 Maintenance Manual

MAINTENANCE MANUAL

YAMADA AIR-OPERATED DOUBLE DIAPHRAGM PUMP

NDP-5
NDP-15

Doc. No. NDP 183M-09

WARNING

• For your own safety, be sure to read these procedures carefully before performing
maintenance on this product. After reading this document, be sure to keep it handy for
future reference.

This maintenance manual covers what you should know about maintenance of the Yamada NDP-5 series
and NDP-15 series Diaphragm Pumps.
This edition is based on the standards for the May 2015 production run. Remember, the specifications are
always subject to change; therefore, some of the information in this edition may not apply to new
specifications.

·Warnings and Cautions

For safe use of this product, be sure to note the following: In this document, warnings and cautions are
indicated by symbols. These symbols are for those who will operate this product and for those who will be
nearby, for safe operation and for prevention of personal injury and property damage. The following
warning and caution symbols have the meanings described below. Be sure to remember their meanings.

If you ignore the warning described and operate the product in an
improper manner, there is danger of serious bodily injury or

death.

If you ignore the caution described and operate the product in an
improper manner, there is danger of personal injury or property

damage.

Furthermore, to indicate the type of danger and damage, the following symbols are also used along with
those mentioned above:

This symbol indicates a DON'T, and will be accompanied by an explanation on something
you must not do.

This symbol indicates a DO, and will be accompanied by instructions on something you
must do in a certain situation.

WARNING

• Before starting maintenance work, cut off the feed air and clean the pump. If air pressure or
residue remain in the pump, there is danger of explosion, or possible poisoning resulting in
serious injury or death if chemicals adhere to the skin or are accidentally swallowed.
(For details on cleaning the pump, refer to Chapter 6 of the Operation Manual.)

• When replacing parts, be sure to use the recommended genuine parts or Equivalents. Use of
other parts may cause a malfunction of the product.
(Refer to Exploded View and Reminder to order correct item on the separate sheets.)

CAUTION

• When it is instructed that special tools must be used, be sure to use the specified tools.
Otherwise, the pump may be damaged.

• Refer to 10.1 "Specifications" in the Operation Manual. Also, remember that the pump is
heavy, and extreme care must be taken when lifting it.

WARNING:

CAUTION :

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

2.3 Misc. --------------------------------------------------------------------------------- 1

3.Ordering Replacement parts --------------------------------------------------- 1

4.Balls, Flat valves and Valve seats

4.1 Removal

■FAT, F S T, BA□, BS□, BPS types ------------------------------------------- 2

■FP□, FV□, FDT types --------------------------------------------------------- 3

4.2 Inspection

■Ball valve types ------------------------------------------------------------------ 4

■Flat valve types ------------------------------------------------------------------ 4

4.3 Installation ------------------------------------------------------------------------- 4

5.Diaphragm and Center rod

5.1 Removal

■FAT, FS T, BA□, BS□, BPS types ------------------------------------------- 5

■FP□, FV□, FDT types --------------------------------------------------------- 6

5.2 Inspection -------------------------------------------------------------------------- 6

5.3 Installation

■B□H, B□S, FPH, FPS

types ------------------------------------------------- 7

■B□C, B□N, B□T, FPC, FPN, F□T

types -------------------------------- 7

6.Pilot valve Assembly, Guide and Bushing

6.1 Removal

■NDP-5 ------------------------------------------------------------------------------- 8

■NDP-15 ----------------------------------------------------------------------------- 8

6.2 Inspection -------------------------------------------------------------------------- 8

6.3 Installation ------------------------------------------------------------------------- 8

7.C spool valve Assembly and Sleeve Assembly

7.1 Removal ----------------------------------------------------------------------------- 9

7.2 Inspection -------------------------------------------------------------------------- 9

7.3 Installation ------------------------------------------------------------------------- 9

8.Retightening of Tie rods -------------------------------------------------------- 10

1

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 material is sucked into material chamber A.
When the center rod is moved full-stroke to the right, the air switch valve is switched, compressed air is
sent to air chamber a (left side, see Fig.1.2), and the center rod moves to the left. The material in
material chamber A is pushed out, and at the same time material is sucked into material chamber B.

Through repetition of this operation, material is repeatedly taken in and discharged out.

2.Tools, etc.

2.1 General tools

▪ Socket wrenches 10mm( NDP-5 ), 13mm( NDP-15 )
▪ Open-end wrenches 10mm ( NDP-5 ), 13mm( NDP-15 ), 21mm( NDP-15 )

▪ Plyer

2.2 Special tools (sold separately)

▪ Cap and disk remover ▪ Sleeve remover

Purpose: Removing the center disk of Purpose: For removing sleeves

FP

□ and FVT and FDT types

2.3 Misc.

▪ Assembly oil Turbine oil none addition class 1( equivalent to ISO VG32 grade )
▪ Nuts M6

X 1( NDP-5 ), M8 X 1.25( NDP-15 )

▪ Grease Urea grease grade (NLGI) No.2

3.Ordering Replacement parts

For accurate and speedy shipment of parts, be sure to order the right parts for your model to distributor
Indicate the part numbers, descriptions, and quantities.

2

4. Balls, Flat valves and Valve seats

4.1 Removal

■FAT, FST, BA□, BS□, BPS types

▪ Remove the 4 retainer bolts from the out manifold, and

remove the out manifold. [Fig.4.1]

▪ Remove the O ring, valve stopper, valve guide, flat valve and

valve seat. (NDP-5) [Fig.4.2]

▪ Remove the O ring, valve guide, ball and valve seat.

(NDP-15) [Fig.4.2]

▪ Turn over the main body assembly. [Fig.4.3]
▪ Remove the 4 retainer bolts from the in manifold, and

remove the base and in manifold. [Fig.4.3]

▪ Remove the O ring, valve seat, flat valve, valve guide and

valve stopper. (NDP-5) [Fig.4.4]

▪ Remove the O ring, valve seat, ball and valve guide.

(NDP-15) [Fig.4.4]