Multiquip ST-45HRM manual ST-45 Pump General Information, Regional Differences

ST-45 PUMP — GENERAL INFORMATION

Regional Differences

Concrete is made by mixing locally available rock and sand with cement and water.For this reason there are great differences in the pumpability of concrete from one region of the country to another.

It is impossible to define a specific mix for each region that the Model ST-45 be will working in.Therefore, the mixes on pages 58-59 will provide a basic guideline for establishing the proper mix design for your area.

Use this information to specify your requirements to your local ready-mix batch plant, contractor and civil engineer.It may take minor adjustments to make a mix pumpable, so you should explain your needs.

The elements that have to be controlled and consistently maintained by the batch plant are:

1.The sizing and mix percentage of rocks, gap graded from the largest down through the smallest sizes.

2.Sand with a sieve analysis that has the proper percentage of fines, ASTM C33 spec.

3.Sufficient cement to produce the required design strength of the concrete and provide the lubricating binder to pump the concrete through the delivery system.

Use a minimum of:

5.The proper amount of water to make a workable slump and plasticize the mix.

In addition, the Mayco Structural Concrete ST-45 Pump can be used to pump a large aggregate hard rock as follows:

1.Pea rock (1/2" minus) pump with mixes being as low as 30% rock and 70% sand. (See page 44, for comments on cleaning the pump.)

2.Shortening pea rock when used with an air compressor and nozzle. (See back pages for recommended set-up.)

3.“Mud Jacking”, high pressure grouting.

500 lbs. of cement/cu yd for 2500 p.s.i. concrete after 28 days.

530 lbs. of cement/cu yd for 3000 p.s.i. concrete after 28 days.

600 lbs. of cement/cu yd for 4000 p.s.i. concrete after 28 days.

4. Admixture pump-aid if necessary.

PAGE 18 — MAYCO ST-45HRM PUMP — OPERATION & PARTS MANUAL — REV. #4 (07/16/04)