Texsteam MX-5 Series: Gas-Driven Chemical Injection Pump for Remote Wellsite Operations

Chemical injection failures at remote locations do not announce themselves politely. Scaled tubing, paraffin buildup, and corrosion breakthroughs accumulate quietly while a pump that needs a power source you do not have sits idle. The Texsteam MX-5 Series was built specifically for that problem: a gas-actuated positive displacement pump that runs on the same supply gas already present at the wellhead, needs no external power, and delivers consistent chemical dosing from 1 GPH all the way to 63.3 GPH depending on plunger size and configuration. Every unit ships with mounting hardware included and every model shares the same 2-inch stroke length, which simplifies parts inventory across a field with mixed installations.

What is the Texsteam MX-5 Series and how does it work?

The Texsteam MX-5 is a gas-actuated positive displacement pump designed for remote chemical injection where electrical power is unavailable or undesirable. It uses pressurized supply gas at 30 to 145 psig to drive a plunger through a fixed 2-inch stroke, injecting precise chemical volumes into a pipeline or wellbore on every cycle.

A key mechanical distinction separates the MX-5 from spring-return gas pumps: there are no springs in the power cylinder. Spring-return designs rely on spring force to complete the return stroke, and spring fatigue over time introduces cycle inconsistency. The MX-5 uses gas pressure on both sides of the piston to execute a positive-cycle operation, meaning each stroke is driven mechanically rather than relying on stored spring energy. The pump is a product of Texsteam, operating as part of Baker Hughes (formerly Dresser, LLC), and the MX-5 fact sheet is catalogued under part number NGS.IPG.0008a. Stroke speed is adjustable from 1 to 60 strokes per minute across all four plunger sizes and both simplex and duplex configurations.

What flow rates and pressures does the Texsteam MX-5 deliver?

The MX-5 Series spans four plunger sizes and delivers simplex flow from 1 GPH up to 34 GPH maximum, with duplex configurations reaching 63.3 GPH. Maximum discharge pressure varies by plunger diameter, with the smallest plunger reaching 4,400 psig and the largest reaching 2,000 psig at matched supply conditions.

The four models map to specific operating envelopes. The MX55 (1/2-inch plunger) reaches a maximum simplex flow of 5.4 GPH and a discharge pressure ceiling of 10,000 psig at 145 psig supply, making it the highest-pressure option in the series. The MX56 (3/4-inch plunger) delivers up to 12.9 GPH simplex with a maximum discharge pressure of 6,000 psig. The MX57 (1-inch plunger) pushes up to 23 GPH simplex, 3,250 psig maximum. The MX58 (1-1/4-inch plunger) is the highest-volume model at 34 GPH simplex and 63.3 GPH in duplex configuration, with a maximum discharge pressure of 2,000 psig at 145 psig inlet. Operators selecting between plunger sizes face a direct trade-off: higher flow requires a larger plunger diameter, which reduces the achievable maximum discharge pressure.

How do simplex and duplex configurations differ on the MX-5?

Simplex MX-5 pumps use a single plunger and power cylinder, while duplex units run two plungers in parallel off the same drive, approximately doubling the volumetric output at equivalent stroke speeds and supply pressures. Both configurations share the same overall height and width at 10.05 inches and 7.88 inches respectively.

The dimensional difference between configurations is length: the simplex body measures 16.35 inches overall, while the duplex extends to 25.58 inches. Both use the same 1/4 NPT air and gas inlet, 1/2-inch NPT suction connection, and 1/2-inch NPT discharge connection, so field plumbing is interchangeable. All MX-5 pumps, simplex or duplex, mount horizontally, and mounting hardware is included with each unit. This means a field crew can upgrade from a simplex to a duplex installation using the same pipe connections and mounting pad footprint with only the pump body changing. Both configurations are available off the shelf, which matters when an injection pump fails and the nearest repair facility is hours away.

Why do ceramic plungers extend service life on the MX-5?

Ceramic plungers are an optional upgrade on the Texsteam MX-5 that extend both plunger service life and packing life compared to standard metallic plungers. Ceramic material resists surface wear and corrosive chemical attack more effectively than steel in aggressive injection services, reducing the abrasive contact that degrades packing over time.

The interaction between plunger surface finish and packing wear is the core reason ceramic matters in chemical injection. A worn or pitted metallic plunger surface accelerates packing degradation because the packing must conform to surface irregularities under pressure on every stroke. Ceramic plungers maintain a consistent surface finish over a longer operational period, which means packing seats more uniformly and seals more reliably between maintenance intervals. The MX-5 also incorporates adjustable packing as a standard design feature, allowing field personnel to take up packing slack as wear accumulates without requiring pump shutdown or disassembly of the power cylinder. This is a planned, non-intrusive maintenance action. Combined with a wide selection of compatible packing materials, operators injecting corrosive biocides, methanol, scale inhibitors, or other specialty chemistries can match packing compound to the specific fluid being handled.

How does supply gas recycling affect operating cost on remote installations?

The MX-5 Series includes the ability to recycle unused supply gas back into the process rather than venting it to atmosphere. On remote gas-driven installations where supply gas is metered or has a recoverable value, venting drive gas on every stroke represents a continuous operating cost that compounds over months of continuous duty.

Supply gas consumption figures from the MX-5 performance data illustrate the scale of this consideration. The MX58 duplex operating at 100 psig supply requires up to 96 SCF per day; the MX57 at the same pressure uses up to 155 SCF per day. At higher supply pressures and maximum stroke speeds, daily gas consumption rises proportionally. Gas recycling capability allows that exhaust gas to be routed back into the line rather than lost to atmosphere, which also reduces emissions at the wellsite, a compliance consideration at sites subject to methane venting regulations. For a deeper look at how chemical injection inefficiencies accumulate into larger operating losses, the article on why your chemical injection system is bleeding money every single day breaks down the common failure modes in detail.

How is the Texsteam MX-5 ordered and what does the model number mean?

The MX-5 model number encodes three decisions: series, plunger size, and configuration. The format is MX-5[plunger digit]-[config digit], where the plunger digit (5 through 8) corresponds to 1/2-inch, 3/4-inch, 1-inch, or 1-1/4-inch plunger diameter, and the config digit (1 or 2) specifies simplex or duplex.

Two common ordering examples: MX57-1 specifies an MX-5 Series pump with a 1-inch plunger in simplex configuration; MX58-2 specifies the 1-1/4-inch plunger in duplex configuration for the highest available flow. When ordering, buyers also need to specify whether the optional ceramic plunger is required and which packing material is appropriate for the injection chemical. Because all four plunger sizes share the same 2-inch stroke length and the same 1 to 60 SPM stroke speed range, the plunger diameter selection is the primary variable controlling both the maximum flow rate and the maximum achievable discharge pressure for a given supply gas pressure. The Texsteam contact address for technical specification questions is 16240 Port Northwest Drive, Houston, TX 77041, with a toll-free number of 1-800-945-9898.

When should you choose the MX-5 over other Texsteam gas pump series?

The MX-5 occupies a specific performance band within the Texsteam gas pump family. Operators needing flows above 63.3 GPH, or those working with different mechanical drive architectures, should evaluate other series before defaulting to the MX-5.

The Texsteam Series 5100 Gas/Pneumatic Pump and the Texsteam Series MXG Gas/Pneumatic Pump serve related but distinct application segments within the broader gas and pneumatic pump category. The MX-5’s particular strengths are its spring-free positive-cycle power cylinder, the gas recycling feature, the adjustable packing for non-intrusive maintenance, and the compact horizontal footprint that fits tight skid spaces. For assembly-level components and service parts supporting Texsteam installations, the Texsteam TC 2142 pump assembly component is also available through PE Energy. For applicable industry standards governing chemical injection pump installations in oil and gas production, the American Petroleum Institute standards library provides the relevant API RP documents covering chemical injection system design requirements.

What are the primary applications for the Texsteam MX-5 chemical injection pump?

The MX-5 Series is purpose-built for remote wellsite chemical injection where no electrical infrastructure exists. The gas-actuated drive eliminates the need for generators, solar arrays, or instrument air compressors.

Core applications include corrosion inhibitor injection into gas gathering lines, scale inhibitor dosing into producing wellheads, methanol injection for hydrate suppression in subsea or cold-weather surface applications, biocide injection into water handling systems, and paraffin inhibitor treatment in crude oil production. The MX-5’s supply gas pressure range of 30 to 145 psig maps directly to the available line and casing pressures found on the majority of producing gas wells, meaning no pressure reduction equipment is required in most installations. The no-spring positive-cycle design is particularly relevant in cold-climate operations where spring-return pumps lose cycle consistency as spring steel properties change with temperature. The adjustable packing feature reduces the frequency of full pump changeouts in the field, which matters most on unmanned remote installations where service visits are costly and infrequent. Operators building out or auditing a chemical injection program should review the full range of available gas and pneumatic pumps to confirm the MX-5 plunger size and configuration match the actual flow and pressure requirements of each injection point.

When is the Texsteam MX-5 the right choice, and when is it not?

The MX-5 is the right call when the injection site has available supply gas at 30 to 145 psig, requires flow rates within the 1 to 63.3 GPH range, operates in a remote location without electrical power, and benefits from a pump design that allows packing maintenance without complete disassembly. The optional ceramic plunger makes it the stronger choice in abrasive or highly corrosive chemical injection services where metallic plunger wear is a recurring maintenance problem.

The MX-5 is not the right selection when discharge pressure requirements fall outside its performance envelope for the targeted plunger size, when supply gas is unavailable or too expensive to dedicate to pump drive, or when flow requirements exceed the duplex MX58 maximum of 63.3 GPH. It is also not suited for vertical mounting. All MX-5 pumps must be installed in the horizontal position, and any installation that cannot accommodate horizontal orientation requires a different mechanical approach. For applications that fall outside the MX-5’s range, the broader Texsteam family, including the Texsteam Series MXG Gas/Pneumatic Pump, should be evaluated against the specific site conditions before equipment is committed.