A Magnesium Dissolvable Plug isolates one fracturing stage from the next, holds pressure through the job, then dissolves in formation water and leaves the wellbore open. The gap between a catalog sheet and a working run is wider than it looks. Before you compare quotes, walk through the numbers that decide whether the plug seals, clears on schedule and stays inside your operating window.

1. What the plug does

A Magnesium Dissolvable Plug seals a stage during multi-stage fracturing, then corrodes away in saline formation water once the job is done. No milling, no drill-out. The well returns to production with a full-bore, debris-free opening. That is the entire value: isolation when you need it, an open wellbore when you do not. Three models cover the range — M1, M2 and R1. Model names tell you less than the operating window does. Match the plug against the conditions below instead of picking by label.

1.1 The all-magnesium build

Every component that meets the formation is made to dissolve: center mandrel, cones, slips, retaining rings, guide shoe, shear pins and the releasing sub. The water-swellable rubber element hydrolyzes in brine. Used with a matched same-specification dissolvable fracturing ball, the system seals a stage and clears as a single piece. Because nothing is left behind to grind out, the whole string can be designed around clean, staged flowback.

1.2 Why a clean full-bore matters

Once dissolution completes, the well is open at full internal diameter. Production starts without waiting on milling, which shortens turnaround and avoids the debris a milled plug leaves behind. In a multi-stage string that difference repeats at every interval, so the plug you choose shapes the entire completion schedule, not just one run. That is why selection is worth doing deliberately rather than repeating whatever the previous job used.

2. Size: match the OD to the casing

Outer diameters are Φ40, Φ75, Φ100, Φ120 and Φ126 mm; overall length spans 500 to 2100 mm. Match the OD to your casing and pick length by the setting interval. A plug that clears the drift is a plug that runs without trouble. Get this wrong and every later step — setting, sealing, dissolution — inherits the problem. Re-check the casing record before you commit, and state the OD and length you need in the quote so the supplier quotes the right size.

3. Working conditions: temperature and pressure

Working temperature runs 30 to 150 °C, and rated pressure on this Magnesium Dissolvable Plug is 70 MPa. Confirm the well stays inside both windows before ordering. Temperature decides how fast the alloy corrodes; pressure decides whether the seal holds during the stimulation. The sealing test holds 49 MPa, or 70 percent of rated, for 30 minutes with a pressure drop under 0.5 MPa. Ask for that test result. It is the fastest check on whether the sealing design actually holds at your expected downhole pressure, and a maker who cannot show it should raise a flag.

4. Dissolution timing depends on the water

Dissolution takes 7 to 15 days in 0.3% to 3% KCl saline formation water. That window is not fixed. Salinity, temperature and well conditions all move it, and the maker's note states actual performance can vary from the datasheet. If your flowback schedule is tight, say what your brine looks like up front and ask what the plug does at your real conditions rather than assuming the midpoint holds. A plug that clears too early or too late can disrupt the sequence you planned for the rest of the string.

5. Setting load and running method

Setting load is 150 to 200 kN. Running goes by wireline at no more than 30 m/min, or pumped at 1.5 to 2.0 m³/min. Confirm your wireline unit or pump schedule fits before you book the run. A plug that fits the well but not your crew is a delay you can avoid by checking this early, when there is still room to switch models or adjust the running plan. Two identical-looking quotes can differ in exactly this detail, so read it before signing.

6. Storage and shelf life

Store sealed in a dry warehouse at 5 to 35 °C. Shelf life is 6 months. These plugs start reacting the moment they see brine, so dry storage is not optional. Track stock age and rotate it. An old plug that has sat near humidity is a risk you do not want to discover at the setting depth. Include storage in your planning, because a good plug stored badly performs like a bad one.

7. Checklist before you order

A Magnesium Dissolvable Plug you intend to run should clear this list before you commit:

OD matches casing; length suits the setting interval

Well temperature and pressure stay inside the operating window

Dissolution time fits the flowback schedule

Setting load and running method match the crew's equipment

Sealing test result available from the maker

Storage plan is dry, sealed and within the 6-month shelf life

Selecting a Magnesium Dissolvable Plug comes down to a short list: OD, temperature, pressure, dissolution time, setting load and storage. Get those right and the plug isolates when it must and clears when it should. Meiyin Technology supplies these plugs in M1, M2 and R1, built entirely from dissolvable magnesium alloy, and publishes the data sheet above so you can verify each figure before buying.