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close this book A training manual in conducting a workshop in the design, construction, operation, maintenance and repair of hydrams
close this folder Session 16: Use of multiple rams (1½ hours)
View the document Handout 16A: Series hydram installation
View the document Handout 16B: Waste water series hydram installation
View the document Handout 16C: Parallel hydrams
View the document Handout 16D: Sample problems

Session 16: Use of multiple rams (1½ hours)

Time 1½ hours


By the end of this session trainees will describe how multiple rams, in series or parallel can be used in situations where h:H ratio, L:D ratio, or D make single ram unpractical or impossible.


In small groups, trainees will solve problems to determine that single ram is impossible, and describe and size multiple system for meeting water need. Large group will discuss advantages/disadvantages of these systems, including cost efficiency.


Handouts 16A, 16B, 16C, 16D


Problems 16A, 16B, 16C on flip chart


Flip charts, markers



1. Introduce session by reviewing limitations of hydram in terms of:

10 min.

- maximum h:H


- L: D ratios


- cost of galvanized pipe in large sizes


State objectives of session.


2. Form 3 small groups and assign each group one problem form Handout 16D. Distribute the relevant diagram (16A, B. or C) to the appropriate group.


The group task is to:

Allow 30 minutes for this.

- solve problem


- determine why single ram will not work


- study diagram and determine why the multiple ram arrangement will work


- size the multiple ram system


- plan 10 minute presentation to the large group


3. Representatives from each group present and answer questions.

30 min.

4. Ask large group to describe any additional advantages/disadvantages of multiple ram systems, any other situation they might be used in.

10 min.

5. Ask participants what application series/parallel rams have at their sites.


Handout 16A: Series hydram installation

Attachment 16-A

Site development

Handout 16B: Waste water series hydram installation

Attachment 16-B

Waste water series hydram installation

Handout 16C: Parallel hydrams

Attachment 16-C

Site development

Handout 16D: Sample problems

Attachment 16D

Problem 16A:

How much water can be pumped to a delivery head of 200 feet, when there is a drive head of 2 feet, a supply of 50 gpm, and an assumed efficiency of 50%?

Problem 16B:

A community of 200 people, with 70 cows, needs 5 gpd per person and 15 gpd per cow. A spring flows at a rate of 15 gpm, H = 10', h = 100', n = 50%, L:D = 960. How can the community's needs be met?

Problem 16C:

How much water can be delivered to a supply tank 50 feet above a hydram when the drive head is 5 feet, the hydrams efficiency is 50%, the flow rate of the water is 30 gpm, and the largest drive pipe available is 2"?