Allied 797CS / Rammer G100
These two hammers are often compared.

Model
Energy
Class
(ft lbs)
AEM/CIMA
Energy
(ft lbs)
Tool
Diameter
Recom.
Carrier
Weight
(tons)
Working
Weight
(lbs)
Impact
Freq.
(bpm)
797CS
$123,000.00
9,000
4,955
6.5 in.
34-50
7,200
320-600
G100
$118,000.00
11,000
4,357
6.7 in.
44-77
8,400
550
Energy Class
Is a general classification used by the industry. The manufacturer places its hammer into whichever "class" it wishes without scrutiny of any organization.

AEM/CIMA Energy
An independant association which attempts to classify or rate various types of equipment that has no standards.

Competive Comparison
Allied 797CS Hy-ram
vs.
Rammer G100

HAMMER BODY

Allied 797CS

The 797CS Hy-Ram is the state of the art design featuring a no sleeve design in the main body. It uses a one-piece cylinder body, which allows for closer piston to body clearances. This means fewer parts in critical areas. The tighter piston clearance of the Allied design provides for greater hydraulic power transmission efficiency. One piece body requires fewer seals and has very little potential for service problems. The hammer also operates in a closed filter hydraulic system.

Rammer G100

The Rammer G100 uses five moving parts - piston, main valve, pressure control valve, inlet check valve & springs. The potential for service problems and failures is greatly compounded.

AUTO-CONTROL SYSTEM

Allied 797CS

The 797CS autocontrol system automatically shifts if the tool penetrates 1/2" or greater into the work then the next blow energy is reduced from 100% power to 50% power. This system adjusts impact energy to increase hammer efficiency and productivity while best protecting the hammer and carrier from wear and damage such as: - Idle blow occurrances (i.e., when tool slips or breaks through material being broken) - False contact pressure (i.e., when the manner box bracket contacts ground material) - In soft material (i.e., when tool penetrates the material deeply on many blows)

Rammer G100

The Rammer G100 has no control system. The CITY-PRO version has a manual power adjustment feature that must be adjusted by the operator in the cab. This becomes cumbersome since job conditions and requirements are constanly changing.

AUTOMATIC SHUT-OFF

Allied 797CS

The 797CS auto shut-off features prevent against "blank firing" and prevent against excessive heat build up and hammer damage.

Rammer G100

The Rammer G100 has no auto shut-off. It will fire whether the tool is engaged or not. With this design, blank firing cannot be prevented when the hammer breaks through material or slips off the work. Energy is transferred into the hammer and carrier and not into the work. This excelerates wear and increases maintenance and repair of the hammers impact ring and piston. Also can lead to early tie bolt failure.

TOOL DIAMETER

Allied 797CS

Allied's full body piston and tool design are matched to develop the to transfere maximum energy at impact area.

Rammer G100

The Rammer G100 piston is designed with a stepped end at the tool impact point smaller than the rest of the piston. The design allows for high stress concentrations to develop at the transitioni diameter and is prone to premature failure.