Selecting the Best Hydraulic Pessure Sensor

Posted on Jan 25, 2016 by Kathy DeGlandon


Gauge savers, piston separators, and 4:1 deboosters all protect hydraulic gauges from drilling fluids and debris, but they do so in different ways. Although Crown offers a complete line of hydraulic pressure sensors, knowing the best one for your drilling application will protect your hydraulic gauge and ensure that it provides the most accurate reading possible. What Is a Diaphragm Protector? A d ...


Gauge savers, piston separators, and 4:1 deboosters all protect hydraulic gauges from drilling fluids and debris, but they do so in different ways. Although Crown offers a complete line of hydraulic pressure sensors, knowing the best one for your drilling application will protect your hydraulic gauge and ensure that it provides the most accurate reading possible.

What Is a Diaphragm Protector?

A diaphragm protector (CD106), also called a gauge saver or E17, consists of a check valve, an outer housing, diaphragm cup, nut retainer and 1502 wing nut. These protectors are the most basic form of gauge saver, using a diaphragm cup to keep harsh drilling fluids away from the gauge. The diaphragm cups are available in rubber (CD200) and Viton rubber(CD200-1). Viton rubber cups are used with harsher drilling fluids, H2S, acids and cements, where the CD200 is used in most regular drilling applications.

How does a Diaphragm Protector Work?

Red hydraulic fluid enters the lower part of the diaphragm protector via the 1502 wing nut and fills the rubber cup diaphragm (CD200). The rubber cup fills, and as it does, it pushes against the housing’s inner walls. As the fluid pushes against the walls, it forces clean hydraulic fluid above the rubber cup into the upper portion of the housing. This fluid is then pumped up into the hydraulic hose that connects to the gauge. The pressure exerted by the rubber cup on the fluid above it is the pressure that the gauge reads. All pressure in this system is 1:1 and does not increase or decrease line pressure.

What is a Piston Separator?

A 1:1 piston separator (CD136) works similarly to a diaphragm protector in that it protects the inner workings of the gauge in its system. Like the CD106, line pressure is is 1 to 1 ratio. However, pressure is transmitted via a piston and diaphragm cup instead of just a diaphragm cup, as with the gauge protector. This sensor consists of piston isolator housing, 1:1 piston sensor piston, diaphragm separator (CD401 rubber cup) and check valve.

How Does a 1:1 Piston Separator Work?

The 1:1 piston separator sensor protects the gauge similarly to the diaphragm protector. As with the the diaphragm protector, the hydraulic fluid enters the sensor via the lower union. The rubber cup diaphragm (CD401) is inverted in this sensor as compared to the CD200 rubber cup diaphragm, and the pressure is exerted on the outer part of the rubber cup, causing the piston to rise. As the piston lifts, it pushes clean hydraulic fluid up a hose into the gauge. The gauge then reads the pressure that the piston is exerting on the hydraulic fluid.

What is a 4:1 Debooster?

A 4:1 debooster (CWDBX15) senses pressure in a hydraulic system just as the CD106 and CD136, but the gauge reads line pressure 4 times less than the actual pressure. This sensor consists of a 4:1 debooster housing, 4:1 piston, debooster cap, check valve, hex stainless steel cross, and diaphragm separator (CD401)and 1502 union.

How Does a 4:1 Debooster Work?

Similar to the 1:1 piston separator, this sensor has a diaphragm cup and piston in it. However, what makes a 4:1 debooster different is that the housing is engineered to fill with fluid but to reduce the pressure coming into the sensor at a ratio of 4 to 1. Therefore, if the pressure coming into the lower sub is 16,000 psi, then the gauge reads 4,000 psi, which is ¼ of the original 16,000 psi.

 

 

Advantages of Each Hydraulic Pressure Sensor

All Crown pressure sensors are engineered to be durable and to withstand the harshest oilfield conditions. They provide protection of sensitive gauge internals, keeping the Bourdon tubes and linkage assemblies from damaging debris and harsh drilling fluids. All of our sensors can be repaired easily in the field, and with proper maintenance, can last for years. However, each sensor can be used for a variety of applications, and knowing the benefits of each will help you to make the right choice for your drilling application.

Gauge Protector
  • Affordable option for most applications
  • Easy-to-use with remote mounted gauges
  • Rubber cup protects gauge from drilling fluids
  • Two rubber cups available CD200 for regular operations and CD200-1 Viton for H2S
  • Available with systems up to 15000 psi
  • Available with 2” connection, fitting most lower subs in the field
  • 1:1 line pressure sensor
  • Can be configured to work with pressure gauges or chart recorders Can be repaired easily in the field

1:1 Piston Separator

  • Most durable 1:1 pressure sensor
  • Easy-to-use with remote mounted gauges
  • Rubber cup protects gauge from harsh drilling fluids
  • Available with systems up to 15,000 psi
  • Can be configured to be used with pressure gauges or chart recorders
  • Can be used with harsh drilling fluids such as acid and cement
  • Durable construction offers best 1:1 protection for a life-time of operations
  • Repair kit (CKT211) available for easy field repair

4:1 Debooster

  • For use with high pressure applications such as fracking, testing and cementing
  • Reduces line pressure to protect gauge internals
  • Reduced line pressure protects workers from hydraulic, high pressure situations
  • Rubber cup protects gauge from harsh drilling fluids
  • Available for higher pressure system configurations for fracking and cementing
  • Durable construction offers protection for line-time of operations
  • Repair kit (CKT204) available for easy field repair

 

Whether you select a gauge protector, a 1:1 piston separator or a 4:1 debooster, all will serve you well in the field.  Each sensor is durable and dependable, and these hydraulic sensors have been proven to work year after year in the severest oilfield conditions. And, if you still have questions about which gauge protector is right to your application, give us a call or contact us; we’ll be happy to help you select the best sensor for your application.